arts water hammer manual

8/6/2019 Arts Water Hammer Manual

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ARTSARTS

HYDRAULIC DESIGN

SOFTWARE

from

AQUAVARRA RESEARCH LIMITED

U SER MA NU A LU SER M A N UA L May-01


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Copyright 1998-2001 Aquavarra Research Limited; all rights reserved. No part of

this User Manual and the associated software may be copied, transmitted,transcribed, stored in any retrieval system, or translated into any languageor computer language, in any form or by any means, without written

permission from Aquavarra Research Limited.

Disclaimer Aquavarra Research Limited has extensively tested its ARTS softwarewith the objective of producing an error-free high quality product.

However, Aquavarra Research Limited makes no representations orwarranties in respect of the ARTS software or User Manual contents andspecifically disclaims any implied warranties of merchantability or fitness

for any particular purpose.

Trade Marks Windows is a trademark of Microsoft Corporation

Customer

support

Aquavarra Research provides a technical support service to registered

users of its ARTS software suite.

Address Aquavarra Research Limited,

Cannonbridge House,

22A Brookfield Avenue,Blackrock, Co. Dublin,

Ireland.

Tel. +353 1 2783107

Fax +353 1 2783108Email [email protected] www.aquavarra.ie


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Table of Contents1. GETTING STARTED 1-11.1 INTRODUCTION 1-11.2 SCOPE OF ARTS 1-1

1.3 SYSTEM REQUIREMENTS 1-21.4 INSTALLATION 1-3

1.5 STARTING ARTS 1-51.6 UNIT SYSTEM 1-51.7 GETTING HELP 1-61.8 QUITTING ARTS 1-6

2. THE ARTS USER INTERFACE 2-12.1 INTRODUCTION 2-1

2.2 QUICK START 2-1

2.3 THE MAIN DESIGN SCREEN 2-12.4 THE DESIGN SHEET 2-2

2.5 THE TOOL PALETTE 2-32.6 THE SPREADSHEET VIEW 2-4

3. SKETCHING THE SYSTEM LAYOUT 3-13.1 INTRODUCTION 3-13.2 QUICK START 3-1

3.3 PLACING OBJECTS ON THE DESIGN SHEET 3-13.4 SELECTING OBJECTS 3-23.5 RE-SIZING OBJECTS 3-3

3.6 MOVING OBJECTS 3-33.7 DELETING OBJECTS 3-33.8 COPYING AND PASTING OBJECTS 3-4

3.9 DRAWING HYDRAULIC SYSTEMS 3-53.10 CONTINUITY CHECK 3-83.11 DRAWING TIPS 3-9


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4. HYDRAULIC OBJECTS AND OTHER TOOLS 4-14.1 INTRODUCTION 4-14.2 QUICK START 4-1

4.3 ACCESSING PROPERTY PAGES 4-14.4 PIPES 4-24.5 CHANNELS 4-4

4.6 RESERVOIRS 4-54.7 PUMPS 4-54.8 ACTIVATED SLUDGE REACTORS 4-7

4.9 AIR VESSEL 4-94.10 BIOFILTER 4-10

4.11 FLOW DIVIDER 4-114.12 FLUMES 4-124.13 FLOW 4-154.14 MANIFOLD 4-15

4.15 SEDIMENTATION TANK 4-164.16 STORM-OVERFLOW WEIRS 4-174.17 SCREEN 4-19

4.18 DETRITOR 4-20

4.19 JUNCTIONS 4-214.20 THE PROPERTIES TOOL 4-22

4.21 THE WEIR TOOL 4-224.22 THE TEXT TOOL 4-224.23 THE RECTANGLE TOOL 4-22

4.24 THE LINE TOOL 4-22

5. HYDRAULIC ANALYSIS/DESIGN : GENERAL APPLICATIONS 5-1

5.1 INTRODUCTION 5-15.2 PIPE FLOW 5-15.2.1 The Pipe Property Pages 5-1

5.2.2 The Pipe Calculator Tool 5-35.2.3 Pipe systems 5-55.2.4 Pump/rising main systems 5-7

5.3 OPEN CHANNEL FLOW 5-135.3.1 Uniform flow computations 5-135.3.2 The Channel Property Pages 5-13

5.3.3 The Channel Calculator Tool 5-155.3.4 Gradually varied flow 5-155.3.5 Channels in series 5-18

5.4 FLOW MEASUREMENT STRUCTURES 5-195.4.1 Flumes 5-195.4.2 Weirs 5-22


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6. WASTEWATER TREATMENT SYSTEM HYDRAULIC DESIGN 6-16.1 INTRODUCTION 6-16.2 HYDRAULIC DESIGN OF PROCESS UNITS 6-2

6.2.1 Sedimentation tank 6-26.2.2 Biofilter 6-36.2.3 Activated sludge reactor (ASR) 6-5

6.2.4 Flow divider 6-66.2.5 Mechanical screens 6-66.2.6 Detritors 6-7

6.3 HYDRAULIC SYSTEM SPECIFICATION 6-76.3.1 Drawing the system 6-7

6.3.2 Specifying the flow range for the system 6-96.3.3 Preparing for Auto Design 6-96.3.4 Implementing the Auto Design procedure 6-96.3.5 Refining the initial design 6-10

6.3.6 Examining the system at maximum flow 6-116.3.7 Examining the system at minimum flow 6-116.3.8 Examining the system at current/average flow 6-12

6.4 SCREEN DISPLAY OF RESULTS 6-12

6.5 EXAMPLES 6-13

7. WATERHAMMER ANALYSIS AND CONTROL 7-17.1 INTRODUCTION 7-17.2 DATA INPUT 7-1

7.3 ANALYSIS 7-37.3.1 Pump trip-out, without air-vessel protection. 7-37.3.2 Pump trip-out, with air vessel protection 7-4

7.4 EXAMPLES 7-5

8. FILE MANAGEMENT, PRINTING, DATA EXPORT 8-1

8.1 INTRODUCTION 8-18.2 CREATING A NEW SHEET 8-18.3 OPENING/CLOSING FILES 8-1

8.4 SAVING FILES 8-28.5 PRINTING 8.28.6 EXPORT TO OTHER APPLICATIONS 8.3


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Getting Started

1-1

1. Getting Started

1.1 Introduction

Welcome to ARTS, which is an hydraulic analysis/design software package, developed with the needs

of water and wastewater engineers in mind. In scope, it spans the spectrum of hydraulic problems

encountered in water and wastewater engineering as well as incorporating specific features related to

the hydraulic design of wastewater treatment systems. It is operated through a user-friendly graphical

interface, which enables the user to sketch an outline representation of the hydraulic system underconsideration. This sketch is then interpreted by the software in order to return a solution to the

problem at hand.

The operational features of the user interface are explained in detail in the following chapters of this

manual.

A summary of the applied hydraulics, which underpins the ARTS computer coding, is presented in the

Appendix.

1.2 Scope of ARTS

ARTS caters for the following range of hydraulic analysis/design tasks:

PIPES:

(flow of air, water and sludges in closed conduits) simple pipes pipe links containing fittings such as bends and valves pipe manifolds pipe networks, including booster pumps

CHANNELS:

(flow of water in open conduits)

various cross sections gradually varied flow rapidly varied flow decanting channels with distributed lateral inflow storm overflow with distributed lateral outflow

FLOW MEASUREMENT STRUCTURES:

(for measurement of flow in open channels)

broad-crested weir

various critical depth flumes Parshall flume various thin-plate weirs


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Getting Started

1-2

PUMPING INSTALLATIONS:

rotodynamic pump characteristics duty point computation for single or multiple pump systems at rated or other

speeds

WATERHAMMER ANALYSIS:

(analysis and control of waterhammer pressures associated with pump trip-out)

plot of maximum and minimum pressure envelopes plot of transient pressure fluctuation at any point along rising main. selection/design of appropriate waterhammer protection devices, including air

vessel and air valves.

WASTEWATER TREATMENT SYSTEM HYDRAULIC DESIGN:

Hydraulic design of individual process units Setting relative levels of process units for gravity flow Auto design feature to give initial design Linear or distributed systems Report of maximum/minimum total heads for entire system

Computation of hydraulic profile for linear systems

1.3 System requirements

ARTS has been designed to run in Windows 95 or later versions and Windows NT 3.51 or later

versions and hence you must have the appropriate Windows software installed on your PC before you

can install and use ARTS.

The ARTS hardware requirements are the same as required for the Windows interface. The

recommended minimum processor hardware specification is:

CPU 486 or compatible with 16 Mb RAM

a hard disk with at least 10 Mb of free disk space Microsoft Windows NT 3.51 or higher or Microsoft Windows 95 or higher a two-button mouse or other pointing device a printer supported by Windows if you wish to get hardcopy output of your

analysis


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Getting Started

1-3

1.4 Installation

ARTS can only be used when it has been installed on your computers hard disk. The following

procedure describes how to install ARTS directly to your computers hard disk from the supplied CD

ROM. As with any software, before you install the ARTS software on your PC, you should carry out

steps 1 to 3.

To install ARTS on your computer,

1. If you have a back up system, make a back up of your PC.

2. If you are using a virus-detection utility, disable it before running Setup. If you do not disable the

utility, Setup may conflict with it and not run.

3. Make sure that you close all open applications. This includes applications that run automatically

when you start Windows, possibly Microsoft Office or a virus-detection utility.

4. Insert the ARTS CD ROM into your PC.

5. The install procedure should start automatically after a few seconds. If it does not, click on the

START button, and choose Run. A dialog box appears as in Figure 1.1.

6. In the Open: box, type the letter of the drive that contains the CD ROM, followed by :\ and the

word setup. For example, type d:\setup

7. Choose the OK button, and then follow the instructions on

the screen. Setup asks you to close any open applications.

If applications are open, and you need more information

about how to close them, choose the Help button. To close

Help, choose Exit from the File menu in Help.

ARTS is supplied with an installation procedure which creates a working directory on your hard disk,

into which all the ARTS files are transferred.

Figure 1.1 The Run Dialog box


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Getting Started

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Click the Next button to continue installation. You will be prompted for some user information and

details on how you wish to configure the software installation, however, all the options can be left at

their default values.

On completion of file transfer, the installation procedure adds ARTS to the Start menu. When ARTS isinstalled onto a computer, it is installed as an inactive copy. This copy cannot be used fully until it is

activated by means of an activation code as described in the next section.

Activation Procedure:

1. Once the setup procedure has finished (and the computer has been restarted if necessary), run

ARTS by double clicking on the ARTS icon on the desktop.

2. To activate the copy, select Activate from the File menu.

3. ARTS will display several codes.

4. Carefully, make a note of these and send them to your supplier by fax or email.

5. On receipt of the codes, your supplier will issue you with an activation code by fax or email.

6. This activation code should be entered into ARTS by following step 2 and entering the activation

code when prompted.

7. You must now shut down ARTS and restart it for the copy to be fully active.

If you wish to install another copy of ARTS on another machine, you simply follow the steps again and

contact your supplier for another activation code. However, each activation requires the purchase of an

additional license. For more information, see the ARTS help file, available from the main menu.

Figure 1.2 ARTS setup welcome

screen


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Getting Started

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1.5 Starting ARTS

From the Windows Desktop, you can start ARTS by:

Selecting the ARTS icon on the Desktopor

by choosing ARTS from the START menu.

To start ARTS using the desktop icon:

Click the ARTS icon.

Press the ENTER button on your keyboard.

To start ARTS from the START menu:

Click the Start button. Move the cursor to Programs Move the cursor to ARTS Release the cursor when over ARTS hydraulics.

1.6 Unit system

When ARTS is run for the first time, the default unit system is the Systeme International (SI) system.

The default unit system can be changed to US units by clicking on the Tools > Options menu and

selecting the required unit system as displayed in Figure 1.3. The default unit system determines

which units are displayed on the ARTS dialog boxes and windows.

The units used for data input on a dialog window can also be changed to alternative units by clicking

on the unit label, and selecting the desired unit from the menu that appears as displayed in Figure 1.4.

However, all data output will be in standard SI or US units as used in ARTS.

Figure 1.3 Default unit selection

dialogFigure 1.4 Changing individual units


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Getting Started

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1.7 Getting help

To gain access to Online Help select Help from the menu bar at the top of the screen. The online help

contains detailed information regarding problem solving, technical support and user interface.

1.8 Quitting ARTS

From the File menu, Choose Exit, or

Press Alt+F4, or Double-click the Control-menu button at the top-left corner of the ARTS window, or from the Control menu, choose Close


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The ARTS User Interface

2-1

2. The ARTS User Interface

2.1 Introduction

If you already use Windows applications, you will be familiar with the concepts and interface

architecture presented in this chapter. For those who are not familiar with Windows, a careful study of

the introductory subject matter in this chapter is recommended before attempting the tutorials in the

following chapters.

2.2 Quick StartThe ARTS user interface is similar to most vector-based drawing packages. The primary difference is

that objects are drawn using two clicks (one at start, one at end) which is a feature usually found in

CAD packages rather than drawing packages.

2.3 The main design screenTo start-up ARTS,

Select ARTS hydraulics from the Desktop.

The main design screen is displayed, with the main components identified on Figure 2.1

Figure 2.1 The main ARTS window


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2-2

The menu bar: contains a list of menus. You open menus and

then choose commands from them to instruct ARTS to perform

actions. Each menu contains a set of related commands. The File

Menu, for example, contains commands that affect files; the Edit Menu has commands for editing textand graphics, and so on.

To give a command to the software, you must select the command from a menu. To select a

command, place the mouse cursor on the name of a menu, press and hold the mouse button down,

move the mouse to the desired command, and release the mouse button. You can abort a command

by moving the cursor off the open menu before releasing the mouse button. If a menu or a command is

grey, it is not available in the current circumstances. Some menu bar commands can also be

accessed using the icons in the Main Window Tool Bar, immediately beneath the menu bar.

Maximise, minimise and close buttons: these buttons are located at the right-hand end of

the title bar on main and sub-windows. You can reduce a window to the taskbar by clicking on its

minimise button (left button); reducing a window does not close the application, which remains open

and available. Clicking on the taskbar icon restores the window size. You can maximise a window by

clicking on its maximise button (middle button). Clicking on the right button, which has an x on it, will

close the associated window.

Control-menu icon: the control-menu box is located at the top left-hand

end of the title bar on main and sub-windows. A single click on the icon will display

a command list, a double-click on the icon selects its Close command i.e. closes

the application.

2.4 The design sheetThe Design Sheet sub-window is the ARTS workspace on which you construct a schematic

representation of your hydraulic system, using the objects contained on the tool palette.

You can change the window size to suit your drawing space requirements. To do so, position the

cursor on a border of the window (the cursor will change to a double-headed sizing arrow); drag

inwards to reduce the window area or outwards to increase its area. By placing the cursor on the

south-east corner of the window border you can increase/decrease its height and width dimensions

simultaneously.

To move the design sheet to a new position the screen, position the mouse cursor on its title bar,

click and drag.

You can have multiple design sheets open at the same time. You open them the same way as you

open a single file. You can arrange their simultaneous display on screen, using the commands on theWindow menu.


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2-3

2.5 The tool paletteThe tool palette contains a collection of buttons, which either select a tool for drawing hydraulic

objects or execute commands that carry out specific tasks. To pick up (or select) a drawing tool,place the mouse cursor on the button for the object and click. The currently selected tool is

highlighted. Only one tool can be selected at a time. When you click on a new tool, the currently

selected tool is de-selected.

The tool palette is described as "floating" i.e. it can be moved to any position on the main screen. To

move the tool palette to a new position the screen, position the mouse cursor on its title bar, click and

drag.

The following page displays a brief description of the contents of the ARTS tool palette. You can also

use the Quick Help feature to identify a tool by positioning the cursor over its button. After a short time

a small yellow box will appear with a short description of the button you are over.

Figure 2.2 The toolbar


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2-4

Selection toolFor selecting and manipulating

objects

Properties Command IconDisplays the properties of the

currently selected object.

GVF Command IconDisplays the gradually varied

flow plotter, applied to the

currently selected channel

Graph Command IconDisplays a graph. Used with

channels, pipes and flumes

Zoom ToolEquivalent to selecting Zoom

Area from the View menu

Calculator Command IconDisplays the calculator

Flow ToolUsed to create an inflow or

outflow from a system

Pipe ToolFor creating pipes of constant

diameter

Channel ToolFor creating channels of

constant shape and slope

Reservoir Tool

For creating reservoirs of fixedwater level

Pump Tool

For creating rotodynamicpumps

Air Vessel Tool

For creating pressure vesselswith air cushions for use in

waterhammer control

Screen ToolFor creating a water/wastewater

screening device

Flume ToolFor creating a flow

measurement device

Weir ToolFor creating a flow

measurement device

Sedimentation ToolFor creating a primary or

secondary sedimentation unit

Activated Sludge ToolFor creating an open tank type

unit

Biofilter ToolFor creating a biofilter

wastewater treatment unit

DetritorFor creating grit removal

objects

Divider ToolFor creating a flow-dividing

chamber

Manifold ToolFor creating flow distribution

unit

Storm OverflowFor creating a storm overflow

channel with side-weirs

Rectangle ToolFor creating a rectangle

(Graphic only)

Text ToolFor creating text (graphic only)

Line ToolFor creating lines (graphic only)

2.6 Spreadsheet ViewThe spreadsheet view provides a quick means of viewing all of the data on the screen in a spreadsheet

format. It also allows you to sort data by rows and change data by columns. It is particularly useful

when dealing with Networks. You can also use it to highlight objects, by clicking in the Ref Code

Column. This will display an arrow at the location of the object on the screen. When the spreadsheet

view is visible, you cannot manipulate any other of the ARTS windows. To hide the spreadsheet view,click on the Windows close control button (top right hand side of window) or choose Close from the

View menu.

NB When you change a property such as pipe diameter on the spreadsheet view, the flow distribution

in the system may change. If the flow distribution does change, the values in the spreadsheet view

which are dependent on the flow are no longer valid. You must re-run an analysis and then re display

the spreadsheet view in order to see the new flow distribution.


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2-5

Menus

View Menu

The view menu displays the object types which are available. The currently displayed object type ischecked. Selecting another of the menu items will fill the spreadsheet view with the corresponding

objects. The spreadsheet view can currently display the following objects:

Nodes

Pipes

Pumps

Flows

Reservoirs

Edit Menu

The Copy command copies the entire spreadsheet in tab delimited format to the Windows Clipboard

for pasting into a spreadsheet program.

Sort Menu

The spreadsheet view can sort rows in order of an increasing or decreasing parameter. To sort data,

you must select the cells in the column by which you want the sorting done. For example, to view a

list of pipes in order of increasing velocity, select some cells in the Velocity column and the click on

the Sort > Ascending command. Only the rows containing selected cells are sorted. You can select

all the cells in a column by clicking on the column heading.

Change Menu

This displays an input box, which allows you to change the value of all the selected cellssimultaneously. The cells you select must be in the same column, and all the selected cells will be

changed to the same value.

Figure 2.3 The spreadsheet view


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2-6


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Sketching the system layout

3-1

3. Sketching the system layout

3.1 Introduction

In the same way that you might sketch a problem on a piece of paper, when solving problems with

ARTS, you sketch the system you are analysing on the computer screen. ARTS provides you with a

set of hydraulic objects, which are the building blocks for creating hydraulic systems on the screen.

These objects can be placed on the design sheet using the mouse, in a similar fashion to any

Windows drawing package. Once you have constructed your hydraulic system, you can run theappropriate Analysis command to carry out the required hydraulic analysis.

The first step is to draw a sketch of the system on the design sheet. This applies whether the

hydraulic system is a single pipe or channel or a complex series of process units linked by pipes. In

all cases, the system components and configuration are communicated to ARTS by drawing a sketch

diagram on the design sheet.

3.2 Quick StartDraw the system you are trying to analyse as you would on a piece of paper. Draw your pipes and

channels so that they start and end in the objects they are connecting.

Reminder

Click means press and release the left-hand mouse button quickly;

Double-click means press and release the left-hand mouse button twice in quick succession; Drag means move the mouse while holding down the left-hand mouse button;

3.3 Placing objects on the design sheetTo draw an object on the design sheet:

1. Select the desired object type by clicking on its tool button. The selected tool button is depressed

and remains so until another tool button is pressed2. Move the cursor to one of the intended corner positions for the object on the design sheet. The

cursor shape should be in the shape of a cross-hair.

3. Click and then move the cursor to draw an outline of the object to the required size - the cursor

movement traces a dotted outline of the object on the design sheet.

4. When the dotted outline is of the required size, click again to place the object on the design sheet.

If the drawn object is a linear element such as a pipe or channel, its terminal points are identified by a

pair of small black squares, known as selection handles; if it is a process unit such as a tank or

pump, its drawn outline space is identified by a set of 4 selection handles.

Sk t hi th t l t


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3-2

Exercise

Draw the objects shown on Figure 3.1. These will be used again in the next exercise to create Figure

3.2.

3.4 Selecting objectsTo select one object:

If the selection tool is not already selected, click on the selection tool

Click on the object you wish to select

Small black squares appear at the extremities of the selected object to indicate that it isselected

Not selected Selected

PU 1

R 1

R 2

R 3

P 1

P 2

P 3

P 4

Figure 3.1 Reservoirs, pipes and a pump - drawing exercise



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3-3

To select several objects:

If the selection tool is not already selected, click on the selection tool

Drag across the objects you wish to select, enclosing them in the dotted selectionrectangle which appears. The starting point of a selection rectangle must not be at the

same place as one of the objects on the sheet

Small black squares appear at the extremities of each of the selected objects to indicatethat they are selected

3.5 Re-sizing objects

To re-size an object:

Select the object you wish to resize

Place the cursor over one of the selection handles, the cursor changes shape to a double-headed arrow

Drag to re-size

3.6 Moving objects

To move an object:

Select the object or objects that you wish to move

Place the cursor over the object, a small 4-headed arrow appears to the bottom right ofthe cursor arrow

Drag to move to a new location.

3.7 Deleting objects

To delete an object:

Select the object or objects that you wish to delete

Press the Delete key on the keyboard or

Choose Delete from the Edit menu


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3-5

3.9 Drawing hydraulic systems

Pipes and channels:

Both pipes and channel convey fluid from one point to another and can both be regarded as links. An

individual link is defined by the locations of its end points. Any link that starts or terminates at the end

point of another link is considered to be connected to that link. Pipes and channels should start and

end either in another object or at the end of another link. If you try connecting links to the very edge of

other objects, ARTS may not register the connection.

P 1

P 2

J 1

J 2

J 3 R 1

Figure 3.3 Connected pipes

P 3 P 4J 4

J 5 J 6

J 7 R 1

Figure 3.4 Unconnected pipes

Other hydraulic objects:

Treatment process units

These objects should not be placed in other objects. Links are deemed to be connected to a process

unit such as a reservoir or biofilter, if one of the links end points is located within the screen areaenclosed by the screen outline of the process unit. In Hydraulic profile analysis each unit can only

have two connections (one in and one out). In Steady pipe flow and Unsteady pipe flow analysis,

reservoirs can have multiple connections.

P 3

P 4

J 4J 5 J 6

J 7

S 1

Figure 3.5 One inflow and one outflow pipe



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g sys ay

3-6

Pumps

ARTS uses the standard graphical representation of a rotodynamic pump, which distinguishes its

suction/inflow and delivery/outflow points (the central line represents inflow, the tangential linerepresents outflow). Basically, think of a pump as having 2 small pipes coming out from it (one on

each side) onto which you connect your links.

PU 1

Figure 3.6 Pump with one inflow and one outflow pipe

Supply/demand:

The flow object is used to represent either an inflow/supply or an outflow/demand.

To indicate an inflow/supply at a pipe or channel junction:

Draw the flow object on the sheet with the arrow pointing towards the junction (start thedrawing process at a point away from the junction).

To indicate an outflow/demand at a pipe or channel junction:

Draw the flow object on the sheet with the arrow pointing towards the junction (first mouseclick at the junction).

Note: The flow object can only be used at junctions i.e. it cannot be connected directly to a process

unit. All flow objects which are not connected to junctions will be ignored.

Figure 3.7 Inflow Figure 3.8 Outflow



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g y y

3-7

Exercise

Modify the previously drawn object to create a system similar to Figure 3.9. Then select New from the

File menu and draw the linked hydraulic system shown on Figure 3.10.

PU

R 1

R 2

P 1

P 2

P 3

P 4

PU 2

PU 3

P 5

P 6

P 7

P 8

P 9

P 10

P 11

Figure 3.9 Pumping system - system creation exercise

O 1

P 10

P 11 P 1S 1 B 1

S 2

P 2

P 3

P 4

SCR 2

Figure 3.10 WWTP - system creation exercise



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3-8

3.10 Continuity check

When you have completed your layout sketch of the hydraulic system, you can check that the

connectivity of its elements has been correctly interpreted by the software by running the Compile

command from the Analysis menu. On completion of the compilation process, ARTS places asolid

circle over each registered junction according to the following colour coding:

1. pipe-to-pipe junctions are represented by a red circle

2. a green circle is placed at each junction which has registered an inflow or outflow

3. a blue solid circle is placed at all other junctions (channel-to-channel, pipe-to-process unit, pipe-to-channel) that have been registered by the compilation process.

A correctly registered system should comply with the foregoing colour coding and each compiled node

should be represented by a single solid coloured circular dot. Check that your systems match those

displayed in Figure 3.11 and Figure 3.12.

Deviation from the foregoing requirements at any node indicates that its junction connectivity has not

been correctly registered by ARTS i.e. the terminal points of the elements that meet at the junctionsare not sufficiently close for ARTS to conclude that they are connected.

Connectivity faults can be corrected by repositioning the objects on the design sheet.

O 1

P 10

P 11P 1

S 1 B 1

S 2

P 2

P 3

P 4

SCR 2

J 12J 13

J 14

J 15

J 16 J 17

J 18 J 19

J 20 J 21 J 22

green

red

Figure 3.11 WWTP - compile exercise (all nodes blue, except marked)



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3-9

3.11 Drawing tips

1. Make full use of the screen space available for the design sheet by expanding the design window

area to its limiting size.

2. Draw your system to the largest practical scale to allow adequate space for ARTS to print flow and

pressure values on the diagram

3. There is no computational advantage in attempting to make sketch diagrams to approximate scale;

best use of the available drawing area can usually be made by allocating each element in your

system approximately the same screen space. Try to create a schematic of the system under

consideration.

4. Note that each object you draw on the design sheet has a label associated with it. When you move

an object, its label also moves. You can, however, move the label independently of the object by

the selecting the label itself.

5. If you right click on an object, a popup menu will appear allowing you to manipulate the object, e.g.

copy it.

6. When clicking on the design sheet to select an object, the order of preference for selecting is:

labels, nodes, pipes, other objects.

7. Always use the Compile command to check the connectivity of your system before you proceed to

analysis or design

PU 1R 1

R 2

P 1

P 2

P 3

P 4

PU 2

PU 3

P 5

P 6

P 7

P 8

P 9

P 10

P 11

J 1

J 2

J 3 J 4

J 5

J 6

J 7 J 8

J 9

J 10

J 11

J 12

J 13

J 14

red

Figure 3.12 Pumping system - Compile exercise (all nodes blue, except

marked)



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3-10

Hydraulic Objects


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4-1

4. Hydraulic Objects and other tools

4.1 Introduction

Every hydraulic object that you place on the design sheet has properties associated with it. These

properties are accessible via dialog boxes known as Property Pages. For example, a pipe object has

a length property, a diameter property, a surface roughness property etc. When you place an object

on the design sheet you are essentially creating a virtual version of a real world object. For example,

when you place a pipe on the screen and then display its Property Pages, you will find that the pipehas a value for length, diameter as well as its other properties. You will probably have to change these

values in order represent the element of the real world system you are trying to model. Objects that

have not had their initial properties changed are drawn in grey on the design sheet. All objects can be

used individually to design an individual object without using the analysis functions. Not all the objects

can be used with all the analysis functions. For example, Air Vessels can only be used in Unsteady

pipe flow analysis and will be ignored by the other analysis functions.

4.2 Quick StartRight click on an object to get at its properties. Once you have set all the relevant properties of all

objects, choose the analysis function you want to carry out, from the main menu bar.

4.3 Accessing Property PagesTo access the properties of any object,

select the object and then,

press the properties tool button on the toolpalette.

Alternatively, click on the object with the RIGHT mouse

button. A menu should appear over the object. Select

Properties from this menu.

The Property Pages for every object have a similar layout.

The Property pages for pipe objects are displayed in Figure 4-1.

Figure 4-1 Pipe property pages

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Property pages consist of a window with various grouped controls which are accessed via tabs along

the top of the widow. In Figure 4-1 the tabs are Main, Unsteady flow, Extras and Status. Clicking on

a tab displays the properties relevant to the tab caption. For pipe objects, diameter, shape/type,

length and roughness are displayed under the Main tab as these properties are generally of mostsignificance. Drawings with dimensions that are coloured red can be edited.

Important: when finished editing the value in a text box, or a dimension value, you should press the

Enter key on the keyboard to register the new value that you have inserted.

4.4 Pipes

Pipes are conduits flowing full at all times. Pipes are drawn as thin blue lines and can be used with allthe analysis functions.

Main

Diameter (mm / in): the internal diameter of the pipe

Type: the shape of the pipe, rectangular, square or circular

Length (m / ft): the total length of the pipe

Roughness (mm / in): the roughness of the internal wall

surfaceWidth (mm / in): The internal width of the pipe (square and

rectangular pipes only)

Height (mm / in): The internal height of the pipe (rectangular

pipes only)

Unsteady flowThe properties grouped on this tab are used by theunsteady

pipe flow analysis functions only. If you are performing an

unsteady pipe flow analysis, you should set all these values

first. If you are not performing anunsteady pipe flow analysis,

you may leave these values at their default settings.

Wall thickness (mm / in): the average wall thickness of the

pipe

Youngs Modulus (Nm-2 / psi): Youngs modulus for the pipe

material

Material: Selecting a material here will modify the value in the

Youngs modulus edit box, which you can also modify

directly.

Figure 4-2 Main tab

Figure 4-3 Unsteady Tab

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Extras

The extras page contains a list of the fittings currently in the

pipe. The fittings that are in the pipe can be displayed intextual list form or as a graphical plot of elevation versus

chainage, by clicking on the option buttons on the bottom

left.

Chainage (m / ft): distance along the pipe to the location of

the fitting

Elevation (mOD / ftAD): the vertical distance from some

datum to the centre of the fittingTotal K value: The sum of the K values of all fittings

contained in the pipe. You can add to this value, but you

cannot make it less than the sum of the included fittings.

Fitting K value: The K value of the currently selected fitting.

Fitting: Use these two drop down lists to specify fittings to add to the pipe.

New fittings can be selected from the dropdown lists on the top right-hand side. The first list contains

general fitting types, and the second contains fitting sub-types. Once you have selected the desiredfitting type, you can add them to the pipe by clicking on the Add button. Fittings that are already in

the pipe can be removed by clicking on the fitting to remove and then clicking the Remove button. As

an alternative to adding individual fittings, a total K-value can be specified for the pipe.

Note: Each fitting inserted using the Add button, must have a unique chainage, and must not be

located at the beginning or end of the pipe - use the connected nodes to define properties of these two

points.

The addition of fittings depends on the analysis required:

Steady pipe flow and hydraulic profile analyses:

Edit the Total K value if you know the total K for all the fittings in the pipe.

Or

Add fittings at various chainages along the pipe, selecting individual fittings. (ignore elevationaldata)

Unsteady flow - Rising main:

Add chainage and elevational data at various points along the pipe to define the profile of the

rising main, and include fittings if desired. This is particularly important with air valves, see

Chapter 7

Figure 4-4 Extras tab

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Status

Shows the steady state values of the key hydraulic

parameters for the pipe object, based on the currently

specified value in the flow edit box and the current pipeproperties. Entering a new value in the flow edit box will cause

the associated hydraulic parameters to be re-calculated.

4.5 ChannelsChannels are conduits which have a free surface at all times. Channels are drawn as purple lines and

are slightly thicker than the lines for pipes. Channels can only be used in thehydraulic profile analysis

functions.

Main

Type: The shape of the channel, Rectangular, trapezoidal,

circular, U shaped, V shaped and parabolicSide angle (degrees): The angle that the face makes with

the horizontal

Bottom width (mm / in): The width of the bottom of the

channel

Gradient: The slope of the bottom of the channel

Height (mm / in): the height of the vertical side face of the

channel

Length (m / ft): The total length of the channelRoughness (mm / in): The surface roughness of the internal

face of the channel

Status

Shows computed steady uniform flow channel parameter

values for the flow value indicated in the flow edit box. If you

enter a new value in the flow edit box, the associated uniformflow hydraulic parameters are re-calculated.

Figure 4-5 Status tab

Figure 4-6 Main tab


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4.6 ReservoirsReservoirs are tanks with a free surface which is at a fixed

level. Can be used with all analysis procedures.

Main

Surface Level (mOD / ftAD): the vertical distance above

some datum

Status

Reference Code: The name used by ARTS to refer to the

object.

4.7 Pumps

The pump object models rotodynamic pumps. Pumps can be incorporated into systems analysed bytheSteady Pipe Flow, Network andUnsteady Pipe Flow analysis procedures.

Main

Suction diameter (mm / in): The internal diameter of the

pipe connecting to the central line of the pump

Delivery diameter (mm / in): The internal diameter of the

pipe connecting to the tangential line on the pump

Moment of inertia (kg.m2

/ lb.ft2

): For use withwaterhammer calculations only. The sum of the pump and

motor moments of inertia.

Elevation (mOD / ftAD): The vertical distance to the centre of

the pump from some datum. Used in waterhammer

calculations.

Current speed (rpm): The speed at which the pump is

currently running.

Rated speed (rpm): The speed to which the characteristic curves apply (see later re characteristiccurves)

Figure 4-8 Main tab

Figure 4-9 Status Tab

Figure 4-10 Main tab

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H-Q

The characteristic curve for the pump is entered by inputting 3

points from which a fitted curve is calculated and plotted. The

software uses the fitted curve in subsequent calculations.

The 3 control points are marked as 1,2,3. You can select a

point by clicking on the point. Once a point is selected, you

can alter its data using the two text boxes to the right of the

graph. Once you have input the data for all 3 points, press the

Recalculate Curve button. Point 2 must be above a straight

line between points 1 and 3, to ensure a correct curve shape.

You can input the flow data in a variety of units - click on the

edit boxes unit labels and select the desired unit.

Note: Only press the Recalculate Curve after you have entered all 3 control points, otherwise the

software will attempt to fit a curve to invalid data

The 3 control points used to input a pump characteristic curve should be roughly equally spaced along

the curve and should preferably include the start and end points of the curve (i.e. values at zero Q andQmax., respectively).

P-Q

The characteristic curve for power is used in pumping

efficiency and waterhammer calculations. The information is

entered in the same way as the H-Q curve.

Figure 4-11 H-Q tab

Figure 4-12 P-Q tab

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NPSH

The characteristic curve for NPSH is used to check for

cavitation problems. The information is entered in the same

way as the H-Q curve.

Status

Shows computed pump parameter values at the current pump

speed for the flow value in the edit box. If you enter a new

value in the edit box, the pump parameter values are re-

calculated.

4.8 Activated sludge reactorsActivated sludge objects are used inhydraulic profile analysis functions only.

Main

Type: determines whether the tank is circular or rectangular

Max ww inflow (m3/s / ft3/s): the maximum inflow of

wastewater that the unit is designed to deal with. Flows inexcess of this design flow will cause an error to occur when

using the hydraulic profile analysis. Changing this value will

redesign the reactor, therefore you should set this prior to

any other values.

AS Recycle (m3/s / ft3/s): the return activated sludge flow

from a sedimentation unit.

Figure 4-13 The Pump NPSH-Q tab

Figure 4-14 The Pump Status tab


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Radius (mm / in): The internal radius of circular reactors.

Width (mm / in): The internal width of rectangular reactors.

Length (mm / in): The internal length of rectangular reactors.

Collector Channel Outlet: Determines whether the flow out of the collector channel is at one end, orin the centre of the channel (rectangular tanks only).

Plan Area (m2 / ft2): The surface area of the tank (not editable)

Outlet

Specifies the distributed outlet system from the activated

sludge tank. Limits are given for the dimensional data by the

quick help.

Type: specifies the shape of the weirs or submerged portsfrom the drop down list which includes v-notch weirs,

rectangular weirs, plain weir, circular orifices or rectangular

orifices.

Outlet length (mm / in): specifies the length available for the

distributed outflow system

No: The calculated required number of the selected opening

along the Outlet Length.

CollectorSpecifies details of the collector channel into which the flow

from the outlet system discharges.

Slope (1:m): the bed slope of the collector channel

k value (mm / in): the Darcy-Weisbach surface roughness

factor (k)

Inlet drop (mm / in): the drop from the bottom of the outlet

system to the water surface at the upstream end of the

collector channel

Outlet depth (mm / in): the desired outlet depth at maximum

flow. This depth must be greater than or equal to critical depth

for the flow/channel conditions as indicated by the quick help.

Outlet drop (mm / in): the drop from the outlet depth to the

water surface in the sump

Width (mm / in): the width of the collector channel

Length (mm / in): the length of the collector channel is determined by the length of the outlet system(not editable).

Figure 4-16 Outlet tab

Figure 4-17 Collector tab

Hydraulic Objects

U d h ( / i ) h l l d d h f h d d d f h ll


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Upstream water depth (mm / in): the calculated depth of water at the dead end of the collector

channel (not editable)

Height (mm / in): the height of the collector channel (sum of the upstream water depth and the inlet

drop)

Status

Shows computed maximum headloss for unit.


object.

4.9 Air vesselAir vessel objects are used in theUnsteady Pipe Flow analysis function only.

Main

Total volume (m3 / ft3): air vessel gross volume. This is the

primary property and therefore should be set first.

Dimensions (mm / in): air vessels are modelled as

cylinders, (the ends are ignored). Changing one dimensionwill modify other dimensions based on the value set for the

Total Volume.

Initial air volume (m3 / ft3): air volume at steady flow

pumping pressure. This value is linked to the Initial Water

Level.

Initial water height (mm / in): sets the water level at

steady flow pumping pressure. This value is linked to the

Initial Air Volume.

Status

Shows computed maximum headloss for unit.

Reference Code: The name used by ARTS to refer to the object.



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4.10 BiofilterBiofilter objects are used in hydraulic profile analysis functions only.

Main

Max flow (m3/s / ft3/s): the maximum flow for which the unit

is designed. Changing this value causes the unit diameter,

the manifold system and the collector channel to be

redesigned.

Diameter (mm / in): biofilters are circular only

Inlet drop (mm / in): the drop from the manifold orifices to

the surface of the media

Media height (mm / in): the vertical height of the media

Outlet drop (mm / in): the drop at the centre of the biofilter

from the bottom of the media to the apex of the conical floor

below.

Floor slope (1:m): the bed slope of the collecting surface.

Inlet

The inlet system to the biofilter consists of a manifold

distribution system.

No of orifices: the number of orifices per radial arm

Orifice diameter (mm / in): the diameter of each individual

orifice

Manifold k (mm / in): the surface roughness of the internal

face of the manifold pipeworkNo of radial arms: the biofilter can have from 1 to 4 radial

arms

Diameter (mm / in): arm diameter

Orifice spacing (mm / in): distance between individual

orifices

End spacing (mm / in): distance between the last orifice and the end of the pipe.

Some calculated values are displayed for inlet-related hydraulic parameters, including the manifold

inlet velocity, min./max. orifice discharge ratio, the manifold head loss.


Figure 4-21 Inlet tab

Hydraulic Objects

Collector


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Collector

See the collector for the activated sludge object (see 4.8)

4.11 Flow dividerFlow divider objects are used inhydraulic profile analysis functions only.

Plan

A dimensioned plan view of the flow divider, with a single

inflow chamber and multiple outflow chambers.

Max flow (m

3

/s / ft

3

/s): the maximum flow that the divider isdesigned to cater for. Changing this value will redesign the

divider.

No of divisions: the inflow to the chamber on the left is

divided into this number of independent outflows.

Equal division: if this is checked then the outflow

percentage for each outflow chamber will be equal. If it is not

checked, you can edit the individual percentages. Note:

make sure that these add up to 100%, as indicated by theTotal display.

Side

The Side tab shows the computed weir head at maximum

flow.

Drop (mm / in): the drop from the weir crest to the water

surface level in the outflow chamber.

Figure 4-22 Collector tab

Figure 4-23 Plan tab

Figure 4-24 Side tab

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Status


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4-12

Status

Shows the computed head loss at maximum flow.


object.

4.12 FlumesThe flume object can be used for stand alone flume design or can be incorporated in treatment

systems amenable to analysis using the hydraulic profile analysis procedure.

Main

Flume type: specifies the type of the flumeMax. flow (m3/s / ft3/s): specifies the maximum flow which

the flume can measure accurately

Min. flow (m3/s / ft3/s): specifies the minimum flow which the

flume can measure accurately

Channels

The upstream and downstream channels must have the same

dimensions, but can have different slope and different

roughness

The drop down list determines whether the properties

displayed relate to the upstream or downstream channel.

For other properties see 4.5 Channels.

The upstream and downstream channels have a minimum

length specification of 2.5 times the flume head at maximum

flow



Figure 4-27 Channels tab

Hydraulic Objects

Throat


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Throat

Quick help provides limit values for all dimensional data.

These limits should be adhered to.

Width (mm / in): the width of the lowest part of the throat

Side angle (deg): applies to trapezoidal flumes only

Step height (mm / in): optional

Roughness (mm / in): the surface roughness of the internal

face of the flume

Setup: pressing this will create an initial design which is

compliant with design norms (see Appendix). This design isbased on the specified upstream channel dimensions and the

maximum and minimum flow values.

Plan

Length (mm / in): the length of the throat

Expansion slope (1:m): the downstream expansion slope

Side

Displays a longitudinal water surface profile for the flume and

its attached channels. Various parameters for either

maximum flow or minimum flow are displayed using the

option buttons.

Figure 4-28 Throat tab

Figure 4-29 Plan tab


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Calibration


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A plotted graph of flume head as a function of flow is

displayed as well as a fitted H/Q equation for the flume. This

graph may be copied to the Windows clipboard for insertion

into other applications by clicking on the graph with the right

mouse button and selectingCopy.

Status

Displays the modular ratio, upstream Froude number at both

max. and min. flow values; it also prints recommended

design limit values for modular ratio and upstream Froude

number and head loss across the flume at maximum flow.

If the recommended limit values are satisfied, the wordVALID is printed on the Status page; if not, the word

INVALID is printed.

Figure 4-31 Calibration tab


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4.13 FlowThe flow object/tool is drawn on the design sheet as an arrow and is used to represent either an

inflow/supply or an outflow/demand. The flow object must be used in conjunction with a junction/node.An arrow pointing towards a junction (with the point end in the junction) represents an inflow/supply,

and an arrow that points away from a junction (with the tail end in the junction) represents an

outflow/demand. Used in Steady Pipe Flow, Network and Hydraulic Profile analysis functions.

Main

Current flow (m3/s / ft3/s): this is used in all calculations

Minimum flow (m3/s / ft3/s): this is only used with the

hydraulic profile calculations.

Maximum flow (m3/s / ft3/s): this is only used with the

hydraulic profile calculations.

Fluid type: specifies whether the fluid is water, air or one of

several types of sludge (latter relates to pipe flow only).

Fluid temperature (oC / oF): only available if you have

selected Water/Wastewater or air as the fluid type

Solids concentration (kg/m

3

/ lb/ft

3

): only available if youhave selected a sludge as the fluid type

4.14 ManifoldThe manifold object models a submerged manifold in which the manifold liquid has the same

properties as the liquid into which it is discharged.

Main

Specifies the manifold trunk pipe details

Length (mm / in): the total length of the trunk pipe

Diameter (mm / in): internal diameter of the trunk pipeSlope (1:m): Input optional

k (mm / in): the Darcy-Weisbach surface roughness

parameter (k)

No: the total number of laterals (total of both sides)


Figure 4-34 Manifold tab

Hydraulic Objects

Laterals


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Specifies the lateral pipe properties. All laterals are taken as

identical

Length (mm / in): the length of an individual lateral

Diameter (mm / in): the internal diameter of each lateral

pipe

Orifice spacing (mm / in): the distance between orifices

from centre to centre

First pos (mm / in): Distance from dead end to centre of first

orifice

k (mm / in): the internal wall roughness of each lateral

Orifice No: Number of orifices per lateralOrifice diameter (mm / in): the diameter of each orifice on

the laterals

Status

This tab can be used to display various calculated

parameters for the manifold for the flow which is entered in

the flow edit box.

4.15 Sedimentation tankThe sedimentation object can be used as a stand alone or inhydraulic profile analysis procedures

Main

Type: determines whether the tank is circular or rectangular

Max inflow (m3/s / ft3/s): the maximum inflow that the unit is

designed to deal with. Flows in excess of the design flow will

cause an error to occur when using the hydraulic profile

analysis. Changing this value will cause the tank to beredesigned, and therefore this value should be changed prior

to any other values

Underflow (m3/s / ft3/s) : the settled sludge removal rate

Collector Channel Outlet: Determines whether the flow out

of the collector channel is at one end, or in the centre of the

channel (rectangular tanks only).

Plan Area (m2 / ft2): The surface area of the tank (not

editable)

Figure 4-35 Laterals tab



Hydraulic Objects

Outlet

S ifi th di t ib t d tl t t f th


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Specifies the distributed outlet system from the

sedimentation tank. Limits are given for the dimensional data

by the quick help.

Type: specifies the shape of the weirs or submerged ports

The length, over which there is outflow, is taken as the full

width of rectangular tanks and the full perimeter length with

circular tanks.

Collector

See the collector for the activated sludge object (see 4.8)

4.16 Storm-overflow weirsThe storm overflow object can only be used as a stand alone, it cannot be used in a system with any

of the analysis functions..

Main

Displays a dimensioned outline plan of the side-weir storm

overflow.

Length (mm / in): the length of the channel and weirChannel type: specifies the shape of the channel

Max storm inflow (m3/s / ft3/s): The maximum flow that will

enter the upstream end of the storm overflow

Max forward flow (m3/s / ft3/s): The maximum flow that the

designer wants to proceed to treatment

Double Sided Outflow: Determines whether there is a weir

on one or both sides of the channel

Figure 4-38 Outlet tab

Figure 4-39


Hydraulic Objects

Side

Displays the height of the weir crest above the channel


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Displays the height of the weir crest above the channel

bottom at the downstream end. Since the weir is horizontal,

the height of the weir above the channel bottom at the

upstream end will be less than the specified value.

Control depth (mm / in): The downstream depth as

produced by a flume or a weir.

The designer specifies the downstream depth and then

presses the Calculate Weir Height button. The calculated

value will then be displayed.

Section

Specifies the channel dimensions. See 4.5 Channels, for

more information.

Status

Displays the calculated values for the lateral storm-overflow

and also the inflow to the unit (forward flow = inflow - storm-

overflow)


Figure 4-42 Section tab



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Hydraulic Objects

4 18 Detritor


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4-20

4.18 DetritorThe detritor object models a wastewater sedimentation unit for the removal of grit particles. It can be

used for stand alone hydraulic design or can be incorporated in a treatment system amenable toanalysis by thehydraulic profile analysis procedure.

Main

Displays the equation used to calculate the head loss

through the object

k: the resistance coefficient

Status

Displays the head loss through the unit corresponding to the

flow in the edit box



Hydraulic Objects

4 19 Junctions


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4.19 JunctionsJunction/nodes/connections are placed at the end of every link (i.e. pipe or channel) by the Compile

command. Junctions have different properties depending on what type of analysis you are doing andwhere the junction is located. By default, junctions have an elevation property only.

The behaviour of nodes is determined by the analysis that is performed.

When using Steady Pipe Flow, Network Flow and Unsteady Pipe Flow analysis commands, junctions

only have the elevation property

Elevation (mOD / ftAD): the vertical distance above some datum

When using Hydraulic Profile analysis commands, the junctions have different properties depending on

what object they are connecting

Pipe to pipeElevation (mOD / ftAD): as before

Fitting: allows you to specify the fitting at the connection. If the pipes are of different

diameters you should choose a Union (reducer or taper), otherwise you can select one of a

variety of fittings.

Pipe to free surfaceElevation (mOD / ftAD): as before

Submerged or Free discharge: you can select whether you want the pipe to discharge

below surface or above the surface.

Minimum invert submergence (mm / in): only available for submerged pipes. the minimumallowable submergence of the pipe below the free surface. This is usually with respect to the

water levels at minimum flow.

Minimum drop (mm / in): only available for free discharge pipes. This is usually with respect

to the water levels at maximum flow.

Hydraulic Objects

There are several other types of junctions available when performing hydraulic profile analyses. In all

cases the options available are displayed on the property pages once the Assign flows command has


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been executed from the Analysis menu. For more information, see the ARTS help file, which is

available from the main menu.

4.20 The Properties toolThe Properties tool is used to display the properties of the objects drawn on the screen. It can be

used to display the property pages for a selected object on the design sheet, as outlined in section

4.3. Alternatively, it can be used to select the parameter values that are displayed on the design

sheet. This latter function is activated by pressing the Properties tool button, without selecting any

object from the system drawn on the design sheet. This action displays the design sheet Propertiesdialog. Select an Object and Label from the respective drop-down lists on the dialog; press the Update

display button, followed by the OK button; the targeted screen object should now display the selected

label value.

4.21 The Weir toolThe weir tool is operates in the same manner as the flume tool (4.12). It provides for the design of V-

notch, rectangular notch, Sutro and broad crested weirs.

4.22 The Text toolThe Text tool is used to add text to the design sheet. Select the Text tool and draw a text object on

the design sheet at the intended location of the text. Select the Properties tool to display the text

entry dialog; enter the text and press the OK button to display the text at the selected location on the

design sheet.

4.23 The Rectangle toolThe Rectangle tool is used to draw rectangular boxes on the design sheet. Select the Rectangle tool;

click at the required corner location on the design sheet and draw the rectangular box to the required

size.

4.24 The Line toolThe Line tool is used to draw lines on the design sheet. Select the Line tool; click on the design sheet

at the required line starting point and draw the line in the direction and to the length required.

Hydraulic Analysis/Design : General Applications

5 Hydraulic Analysis/Design : General


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5-1

5. Hydraulic Analysis/Design : General

Applications

5.1 IntroductionWhile ARTS has special capabilities in relation to the hydraulic design of wastewater treatment

systems, it has been developed to cater also for the broader general needs of water/wastewater

conveyance engineering. Examples of its application to a general range of steady flow hydraulic

problems are presented in this chapter. These examples are outlined in a step-by-step procedure that

will enable you to execute sample problems in parallel with your reading of the chapter.

5.2 Pipe flowThe designation pipe flow, as used in this manual, refers to conduits that are flowing full throughout

their length (if a pipe is flowing partly filled, it is designated as a channel in conventional hydraulics

terminology). The conveyed fluid may be air, water/wastewater, sewage sludge.

ARTS has several ways of dealing with steady pipe flow problems:

1. the Status page (Fig 4.5, Chapter 4) for a pipe element - this output property page

displays the values of velocity, Reynolds number, friction factor and total head loss, for the

specified flow, based on the properties defined on the Main and Extra property pages for

the pipe element.

2. the Pipe Calculator tool, which provides an instant correlation of friction head and flow.

3. the Steady Pipe Flow command on the Analysis menu - this command analyses theflow and pressure head distribution in multi-pipe systems, including pumps and reservoirs

(points of fixed head).

4. The Graph tool will display a plot of Head vs. Flow for the currently selected pipe

5.2.1 The Pipe Property pages

For steady flow problems, the properties of interest are contained on the Main and Extras pages

(Chapter 4). The computed total head loss shown on the Status property page takes into account the

local losses associated with the total k-value printed at the bottom of the Extras property page. If you

want entry and exit losses to be included, when analysing a single pipe element, the total k-value

must be inclusive of their contribution. (Note that the Hydraulic Profile commands on the Analysis

menu automatically take entry and exit losses into account and hence, where this command is used

to analyse multi-component hydraulic systems, it is not necessary to allow for entry and exit losses in

the assigned total k-values on the Extras property pages).


To use the pipe element Status page as a computational tool:

ith l t i ti i l th d i h t


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5-2

either select an existing pipe or place a new one on the design sheet click on the Properties tool to display the pipes properties change the properties on the Main tab and on the Extras tab as required click on the Status tab enter a flow value by editing the Flow edit box value. A new set of computed values for velocity,

Reynolds number, friction factor and total head loss will appear once the flow has been entered.

Example

Calculate the headloss in a pipe, having an ID of 605mm and a surface roughness of 0.06mm, at a

flow of 0.3m/s. The pipe length is 3,459m and it includes four 90 short-radius bends.

Step 1 Step 2

Draw a pipe on the design sheet (the

pipe will be grey until you set some of

its properties)

Edit the Main property page:

Step 3 Step 4

Edit the Extras property page: Click on the Status page

Solution: The headloss through this pipe is 4.6m at 0.3m/s.


5.2.2 The Pipe Calculator Tool


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This provides a fast and convenient interactive means of examining the inter-relationship of the pipe

flow parameters:

length, diameter, surface roughness, flow and head loss

To use the Pipe Calculator tool:

either select an existing pipe on the design sheet or place a new one on the design sheet click on the calculator tool; the calculator dialog box appears, as on Figure 5.1.

The dialog box displays a set of editable hydraulic parameter values and a corresponding set of

calculator buttons. When you click on a calculate button, ARTS calculates its parameter value as a

function of the current values of the remaining parameters.

Note: If you use the Pipe Calculator to calculate a pipe parameter, this new value is assigned to the

pipe object.

Figure 5.1 The Pipe Calculator


Example


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An old rising main is 6580m long and has an internal diameter of 345mm. Under normal steady state

operational conditions, the flow has been measured at 100 l/s and the corresponding headloss hasbeen measured at 19.5m. Compute the effective pipe wall roughness.

Step 1 Step 2

Draw a pipe on the design sheet

(the pipe will be grey until you set

some of its properties)


Step 3 Step 4

Click on the pipe calculator tool Set the parameters on the pipe calculator

dialog and press k value

Solution: The effective k value is 0.1414mm.


5.2.3 Pipe systems

A pipe system is any collection of pipes that is linked together to create a continuous


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A pipe system is any collection of pipes that is linked together to create a continuous

flow path. ARTS will handle any pipe system configuration, provided:

1. it is correctly drawn on the design sheet

2. it constitutes a feasible conveyance system

3. its boundary conditions are sufficient to define the flow distribution.

Figure 5.2 shows a trunk and branch pipe system, as it would appear on the design sheet after

compilation; it includes five pipe elements, 3 demands, an upstream reservoir plus an additional

supply.

Figure 5.3 shows the flow and head distribution for the system depicted on Figure 5.2 - this is the

screen output that is generated by execution of the Steady Pipe Flow command on the Analysis

menu (each pipe length was set to 100m, each pipe roughness to 0.01mm, each demand to 0.01

m3/s, the independent supply to 0.01 m3/s and the reservoir TWL to 100m AD).

R 1

P 1

P 2

P 3

P 4

P 5

J 1 J 2

J 3

J 4

J 5

J 6

O 1

O 2

O 3

O 4

Figure 5.2 Network system

100.000mOD

0.0200m/s

0.01000m/s

0.0300m/s 0.01000m/s

0.01000m/s100.000m

94.654m

96.152m

83.353m

81.855m

81.855m

0.01000m/s 0.01000m/s

0.01000m/s

0.01000m/s

Figure 5.3 Solved Network system


Figure 5.4 shows a looped pipe system, as it would appear on the design sheet after compilation; it

includes six pipe elements, 2 supply reservoirs and 4 demands.


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Figure 5.5 shows the flow and head distribution for the system depicted on Figure 5.4 - this is the

screen output that is generated by execution of the Steady Pipe Flow command on the Analysis

menu (each pipe length was set to 100m, each pipe roughness to 0.01mm, each demand to 0.01

m3/s, reservoir 1 to a TWL of 100m AD, reservoir 2 to a TWL of 106 mAD).

R 1

R 2

P 1

P 2

P 3

P 4

P 5P 6

J 2

J 3

J 4

J 5

O 1O 2

O 3 O 4

J 9

J 10

Figure 5.4 Looped Network System

106.000mOD

100.000mOD

0.0257m/s

0.00493m/s

0.0107m/s

0.000740m/s

0.00926m/s0.0143m/s

97.527m

97.110m

95.823m

95.808m

0.01000m/s

0.01000m/s

0.01000m/s 0.01000m/s

106.000m

100.000m

Figure 5.5 Solved Looped Network System


Exercise 5.1

Construct a pipe system similar to that shown on Figure 5.2 on your design sheet


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p p y g y g

click on the Compile command in the Analysis menu; the pipe system nodes are now highlightedby coloured circles (pipe-to-pipe junctions are red, inflow/outflow nodes are green, all other nodesare blue). Note that each pipe junction should be represented by a single coloured circle. If there

are two coloured circles at a pipe junction, or the colour coding is not correct, the junction is not

correctly registered by ARTS and a correction must be made (Chapter 3).

select each pipe element in turn (first click the selection tool and then click the drawn pipeelement) and edit its values for diameter, length and surface roughness, using the property pages

so that each pipe is 100m long, with a surface roughness of 0.01mm and a diameter of 100mm.

select each supply and demand in turn and edit its value; edit the current flow value to 0.01m3/s. Click on the Steady Pipe Flow command on the Analysis menu to compute flow and pressure

distribution. The computed flow and head values are printed on the design sheet, as are the flow

directions, as shown in Figure 5.3.

Exercise 5.2

construct a pipe system similar to that shown on Figure 5.4 on your design sheet click on the Compile command in the Analysis menu; the pipe system nodes are now highlighted

by coloured circles (pipe-to-pipe junctions are red, inflow/outflow nodes are green, all other nodesare blue). Note that each pipe junction should be represented by a single coloured circle. If there

are two coloured circles at a pipe junction, or the colour coding is not correct, the junction is not

correctly registered by ARTS and a correction must be made. (Chapter 3).

select each pipe element in turn (first click the selection tool and then click the drawn pipeelement) and edit the values for length and surface roughness, using the property pages so that

each pipe is 100m long, with a surface roughness of 0.01mm and a diameter of 100mm.

select each demand in turn and edit the current flow value to 0.01m3/s.

select one of the reservoir elements and alter its water surface elevation to 106.00m. select the other drawn reservoir element and alter its water surface elevation to 100.00m. Click on the Steady Pipe Flow command on the Analysis menu to compute flow distribution and

head loss. The computed flow values are printed on the design sheet as are the flow directions, as

shown in Figure 5.5.

5.2.4 Pump/rising main systems

The performance characteristics of rotodynamic pumps are normally supplied by pump manufacturersin a graphical format as plots of head versus flow (H/Q), power versus flow (P/Q), required net positive

suction head versus flow (NPSH/Q). The procedure by which these plotted characteristics are

transferred to ARTS via the pump property box pages are outlined in Chapter 4.

ARTS uses the pump and pipe system input data, together with the specified static lift, to compute

the steady pump discharge rate. It can cope with single or multiple pumps in parallel and with single

or complex rising main systems.


Pump installations typically draw water/wastewater from a low-level reservoir or sump and discharge

the pumped flow through a rising main to a high-level reservoir, as illustrated on the ARTS design

sheet in Figure 5.6, which shows a simple single pump/rising main installation.


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You will note that the system pipework, as drawn, has 3 pipe elements - a suction pipe (P1), a

delivery pipe (P2) and a rising main (P3). The suction and delivery pipes are the pipes connected to

the suction and delivery sides of the pump, respectively (commonly designated as the pumphouse

pipework); they normally carry fittings such as valves, bends and tapers, resulting in a significant local

head loss. Where there are multiple pumps, the suction and delivery pipework is typically replicated

for each pump.

Figure 5.7 shows the flow and head distribution for the pump/rising main system depicted on Figure

5.6 - this is the screen output that is generated by execution of the Steady Pipe Flow command on

the Analysis menu

R 1

R 2

PU 1

P 1

P 2

P 3

J 1 J 2

J 3 J 4

J 5

Figure 5.6 Pump system


200.000mOD


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Reminder: the basic property requirements for an ARTS pipe element are that its diameter andsurface roughness should be constant throughout its length.

Exercise 5.3

Draw the system shown on Figure 5.6 on your design sheet

compile your system (Compile command on the Analysis menu) and make any correctionsnecessary (refer Chapter 4).

make the following changes to the system values:reservoirs: change the downstream reservoir level to 200.00m (check that the upstream

sump level is 100.00 m)

suction pipe: use the Extras page of its property box to add a 90o elbow bend.

delivery pipe: use the Extras page of its property box to add a non-return valve, a gate valve

and a 90o elbow bend.

rising main: set its length as 500m and internal diameter to 200mm. use the Steady Pipe Flow command on the Analysis menu to compute the pump duty point check the duty point head, efficiency and required NPSH by entering the duty flow in the flow text

box on the Status property page for the pump.

100.000mOD

PU 1

0.0569m/s

0.0569m/s

0.0569m/s

100.000m

94.289m

215.439m

206.204m

200.000m

Figure 5.7 Solved pump system


Exercise 5.4

Fig 5.8 shows a 3-pump installation with two parallel rising mains, inter-connected.


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Draw the system shown on Fig 5.8 on your design sheet compile your system (Compile command on the Analysis menu) and make any corrections

necessary (refer Chapter 4).

make the following changes to the system default values:reservoirs: set the upstream sump level to 100.00m and the downstream reservoir level to

200.00 m

suction pipes: use the Extras page of its property box to add a 90o elbow bend.

delivery pipes: use the Extras page of its property box to add a non-return valve, a gate valve

and a 90o elbow bend.

rising mains: set lengths as 500m. Enter diameters of 250mm and 200mm, respectively for

the two mains.

use the Steady Flow command on the Analysis menu to compute the pump duty point

check the pump duty point head, efficiency and required NPSH for each pump by examining theStatus property page for each pump.

R 1

PU 1

PU 2

PU 3

P 1

P 2

P 3

P 4

P 5

P 6

P 7

P 8

R 2

P 9

P 10

J 1J 2

J 3J 4

J 5J 6

J 7 J 8

J 9 J 10

J 11 J 12

J 13

J 14

Figure 5.8 Multi pump system


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5.3 Open channel flowThe defining characteristic for open channel flow is the existence of a free liquid surface, i.e. a


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water/wastewater surface in contact with air at atmospheric pressure. In conventional hydraulicsterminology, steady flow in open channels is described as belonging in one of the following three

categories:

1. Uniform flow

2. Gradually varied flow

3. Rapidly varied flow

Uniform flow infers a constant velocity/depth over the channel length;

Gradually varied flow (GVF) infers a gradual variation in velocity/depth over the channel length

Rapidly varied flow infers a localised change in velocity/depth, as, for example, at an hydraulic

jump.

Uniform flow is also further characterised by the channel bottom slope, as follows:

mild slope sub-critical or tranquil flow (Fr < 1)critical slope critical flow (Fr = 1)steep slope super-critical flow (Fr >1)

where Fr is the Froude number (refer to the Appendix for definition and further discussion)

5.3.1 Uniform flow computations

As in all ARTS projects, the first step is to place a channel object on the design sheet using the

channel tool. You can then make the required computations by one of two methods:

(a) using the channel element property pages (refer Fig 4.9, Chapter 4)

(b) by use of the Channel Calculator tool

5.3.2 The channel property pages

To use the channel object Status page as a computational tool:

Either select an existing channel on the design sheet or place a new one on the sheet Click on the Properties tool to display the channels properties. Edit the channel properties as required Click on the Status tab.


Enter a flow value in the Flow edit box; computed values for normal depth, mean velocity andFroude number will be displayed. The computed critical depth, critical slope and channel capacity

(flowing full value at normal depth) are also displayed.


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ExampleCalculate the normal depth in a concrete U-shaped channel, which has a base width of 1200mm, a

gradient of 1 to 1500 and is used to convey sewage at a flow rate of flow 1.65m/s

Step 1 Step 2

Draw a channel on the design sheet (the

channel will be grey until you set some of

its properties)


Step 3

Click on the Status page.

Solution: The normal depth is 1085mm at 1.65m/s.



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5.3.3 The Channel Calculator tool

The channel-calculator tool provides a fast and convenient

interactive means of examining the inter-relationship of the

channel parameters under uniform flow conditions:

length, k-value, flow, flow depth and head loss

click on the channel tool and draw a channel element on thedesign page

click on the calculator and the channel calculator dialog boxappears, as on Figure 5.12.

The dialog box displays a set of hydraulic parameter values and a corresponding set of calculator

buttons. When you click on a parameter calculator button, ARTS calculates its parameter value as a

function of the current values of the remaining parameters.When the dialog box first appears, its text boxes contain editable default values. Note that ARTS

provides the option of using velocity instead of flow.

5.3.4 Gradually varied flow

ARTS provides a versatile capability for the analysis of gradually varied flow (GVF) by use of the GVF

tool on the tool palette, with the aid of which you can analyse and plot GVF profiles for a wide range ofchannel GVF flow conditions:

Figure 5.12 Channel calculator

Figure 5.13 GVF Plotter


Either select an existing channel on the design sheet or place a new one on the sheet Click on the Properties tool to display the channels properties. Edit the channel properties as required, then click OK Click on the GVF tool


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the dialog box shown on Figure 5.13 appears on the screen; it shows1. a channel outline with water depth values at its ends

2. check boxes for the specification of upstream and/or downstream control water

depths.

3. edit boxes for the specification of the end inflow and lateral inflow rates;

4. option buttons for the selection of output format - plot or tabulation

5. command buttons for Plot and Done actions.

clear the check boxes for upstream and downstream controls

specify end and lateral inflow values by editing the edit box values select the Plot option and click the Plot command button;

the normal and critical depth lines are plotted on the channel profile (note the relative positions

of the normal and critical depth lines - if the normal depth line is above the critical depth line,

the flow is sub-critical, whereas if it is below the critical depth line the flow is super-critical).

To enter a downstream control depth:

Click the Downstream control checkbox Enter the downstream control depth by editing its current value

To enter an upstream control depth:

click the Upstream control checkbox; enter the upstream control depth by editing its current value

You may specify an upstream control or a downstream control or both or neither.

click on the Plot command button to plot the GVF profile.

Feasible control depth specifications are summarised in Table 5.1

Table 5.1

GVF control depth specification

(parameters ycont = control depth; yN = normal depth yC = critical depth)

Channel slope

Mild Steep

Upstream control ycont < yC ycont < yC

Downstream control ycont > yC ycont > yC

Upstream + downstream control* upstream:

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