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AutodeskAlgorSimulation 2011

Seminar Notes


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II AutodeskAlgorSimulation 2011 Seminar Notes 3/15/2010


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AutodeskAlgorSimulation 2011 Seminar Notes 3/15/2010 III

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Autodesk Algor Simulation 2011 Seminar Notes

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AutodeskAlgorSimulation 2011 Seminar Notes 3/15/2010 V

TABLE OF CONTENTS

Introduction .................................................. 1

Overview ........................................................................................................................................1

Software Installation, Services, and Support ...............................................................................1

Installing and Running Autodesk

Algor

Simulation ...........................................................1System Requirements ...........................................................................................................2

Autodesk Algor Simulation Help ...........................................................................................3

Subscription Center ...............................................................................................................4

Web Links ..............................................................................................................................4

Tutorials .................................................................................................................................4

Webcasts and Web Courses ................................................................................................4

How to Receive Technical Support ......................................................................................5

Updates..................................................................................................................................5

Background of FEA .......................................................................................................................6

What is Finite Element Analysis? .........................................................................................6

Basic FEA Concepts .............................................................................................................7

How Does Autodesk Algor Simulation Work? ......................................................................9

The General Flow of an Analysis in Autodesk Algor Simulation .........................................9Stress and Strain Review .......................................................................................................... 10

Equations Used in the Solution .......................................................................................... 10

Limits of Static Stress with Linear Material Models ........................................................... 11

Mechanical Event Simulation (MES) Overcomes Limitations .......................................... 11

Hand-Calculated Example ................................................................................................. 12

Heat Transfer Review ................................................................................................................ 13

Equations Used in the Solution .......................................................................................... 13

Linear Dynamics Review ........................................................................................................... 14

Chapter 1: Using AutodeskAlgorSimulation ................ 15

Chapter Objectives .................................................................................................................... 15

Navigating the User Interface .................................................................................................... 15

Toolbars .............................................................................................................................. 17Using the Keyboard and Mouse ........................................................................................ 18

Introduction to the ViewCube ............................................................................................. 19

Additional View Controls .................................................................................................... 20

Legacy View Controls in Autodesk Algor Simulation ........................................................ 21

Steel Yoke Example .................................................................................................................. 22

Opening and Meshing the Model ....................................................................................... 22

Setting up the Model .......................................................................................................... 23

Analyzing the Model ........................................................................................................... 27

Reviewing the Results ........................................................................................................ 27

Creating an Animation ........................................................................................................ 28

Generating a Report ........................................................................................................... 28

Chapter 2: Static Stress Analysis Using CAD Solid Models ... 33Chapter Objectives .................................................................................................................... 33

Archiving a Model ...................................................................................................................... 33

Types of Brick Elements ............................................................................................................ 34

Generating Meshes for CAD Models ........................................................................................ 35

Creating a Mesh ................................................................................................................. 36

Model Mesh Settings Options ......................................................................................... 37


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Tips for Modeling with CAD Solid Model Software for FEA .................................................... 39

Working with Various Unit Systems .......................................................................................... 40

Loading Options ......................................................................................................................... 42

Load Cases......................................................................................................................... 43

Constraint Options ..................................................................................................................... 45

Modeling Symmetry and Antisymmetry ............................................................................. 45

Design Scenarios ....................................................................................................................... 46FEA Object Groups .................................................................................................................... 47

Local Coordinate Systems ........................................................................................................ 48

Defining Materials and Using the Material Library Manager ................................................... 49

Adding Material Libraries and Material Properties ............................................................ 51

Examples of Loads and Constraints ......................................................................................... 54

When to Use Displacement Boundary Elements .............................................................. 54

Using Local Coordinate Systems....................................................................................... 54

Using Surface Variable Loads ........................................................................................... 58

Exercise A: Frame Full to Quarter-Symmetry Model Comparison ......................... 63

Chapter 3: Results Evaluation and Presentation ............. 65


Background on How Results are Calculated............................................................................ 65

How to Evaluate Results ........................................................................................................... 66

Displacement Results ........................................................................................................ 66

Stress Results ..................................................................................................................... 68

Reaction Force Results ...................................................................................................... 70

Inquiring on the Results at a Node..................................................................................... 70

Graphing the Results.......................................................................................................... 71

Presentation Options ................................................................................................................. 73

Contour Plots ...................................................................................................................... 73

Image File Creation ............................................................................................................ 77

Animating FEA Results ...................................................................................................... 78

Using the Configure Report Utility ...................................................................................... 79

Exercise B: Yoke Evaluation of Resul ts and Generati on of a Report .................... 81

Chapter 4: Midplane Meshing and Plate Elements ............. 83


Meshing Options ........................................................................................................................ 83

Element Options......................................................................................................................... 88

Plate Theory and Assumptions .......................................................................................... 88

Loading Options ......................................................................................................................... 89

Example of Defining the Element Normal Point ................................................................ 89

Result Options ............................................................................................................................ 93

Exercise C: Midp lane Meshing and Plate Element Orientation .................................. 95

Chapter 5: Meshing ......................................... 97


Refinement Options ................................................................................................................... 97

Automatic Refinement Points............................................................................................. 97

Global Refinement Options ................................................................................................ 99

Creating Joints ......................................................................................................................... 101

Creating Bolts ........................................................................................................................... 103


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AutodeskAlgorSimulation 2011 Seminar Notes 3/15/2010 VII

Mesh Convergence Testing .................................................................................................... 105

Performing a Mesh Study ................................................................................................ 106

Exercise D: Yoke and Clevis Assembly ..................................................................... 107

Chapter 6: Introduction to Contact ........................ 109

Chapter Objectives .................................................................................................................. 109

Uses for Contact ...................................................................................................................... 109Contact Options ....................................................................................................................... 109

Setting up Contact Pairs................................................................................................... 109

Types of Contact .............................................................................................................. 110

Friction .............................................................................................................................. 111

Surface Contact Direction ................................................................................................ 112

Contact Example ...................................................................................................................... 113

How to Model Shrink Fits: ................................................................................................ 113

Shrink Fit Example ................................................................................................................... 114

Case 1 ............................................................................................................................... 116

Case 2 ............................................................................................................................... 119

Result Options .......................................................................................................................... 120

Exercise E: Yoke Model wi th Contact ........................................................................ 123

Chapter 7: Introduction to Linear Dynamics ................ 125


Modal Analysis ......................................................................................................................... 125

Lumped Masses....................................................................................................................... 126

Load Stiffening ......................................................................................................................... 127

Example of Natural Frequency (Modal) Analysis ................................................................... 128

Meshing the Model ........................................................................................................... 129

Adding Constraints ........................................................................................................... 130

Defining the Materials ....................................................................................................... 130

Analyzing the Model ......................................................................................................... 130

Reviewing the Results ...................................................................................................... 131

Critical Buckling Analysis ......................................................................................................... 132Setting Up a Critical Buckling Analysis ............................................................................ 133

Result Options .......................................................................................................................... 134

Other Linear Dynamics Analyses............................................................................................ 134

Exercise F: Concrete Platform .................................................................................... 135

Chapter 8: Steady-State Heat Transfer ..................... 137


3-D Radiator Example ............................................................................................................. 137

Meshing the Model ........................................................................................................... 138

Setting up the Model ........................................................................................................ 139

Analyzing the Model ......................................................................................................... 140

Reviewing the Results ...................................................................................................... 141Meshing Options ...................................................................................................................... 142

Thermal Contact ............................................................................................................... 142

Element Options....................................................................................................................... 143

Rod Elements ................................................................................................................... 143

2-D Elements .................................................................................................................... 143

Plate Elements ................................................................................................................. 144

Brick and Tetrahedral Elements ...................................................................................... 145


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Loading Options ....................................................................................................................... 147

Nodal Loads...................................................................................................................... 147

Surface Loads .................................................................................................................. 149

Element Loads.................................................................................................................. 153

Body-to-Body Radiation ................................................................................................... 155

Controlling Nonlinear Iterations ........................................................................................ 159

Result Options .......................................................................................................................... 160Exercise G: Infrared Detector Model .......................................................................... 163

Chapter 9: Transient Heat Transfer ........................ 165


When to Use Transient Heat Transfer .................................................................................... 165

Element Options....................................................................................................................... 165

Loading Options ....................................................................................................................... 165

Load Curves ..................................................................................................................... 166

Nodal Heat Source ........................................................................................................... 167

Controlling Nodal and Surface Applied Temperatures ................................................... 168

Result Options .......................................................................................................................... 168

Exercise H: Transistor Case Model ............................................................................ 169

Chapter 10: Thermal Stress ................................ 171


Multiphysics Overview ............................................................................................................. 171

Performing a Thermal Stress Analysis ................................................................................... 172

Exercise I: Disk Brake Rotor Heat-up and Stress ..................................................... 175

Self Study: Linear Dynamics Supplement .................... 177


Overview ................................................................................................................................... 177

Response Spectrum Analysis ................................................................................................. 177

Example of a Response Spectrum Analysis .......................................................................... 179

Exercise SS-1: Tower Model Response Spect rum Analys is ................................. 185

Random Vibration Analysis ..................................................................................................... 187

Example of Random Vibration Analysis ................................................................................. 188

Exercise SS-2: Tower Model Random Vibration Analysi s ..................................... 193

Frequency Response .............................................................................................................. 195

Exercise SS-3: Tower Model Frequency Response ............................................... 199

Transient Stress (Modal Superposition) Analysis .................................................................. 201

Transient Stress (Direct Integration) ....................................................................................... 204

Exercise SS-4: Pressure Vessel Model Transient Stress (Direct Integration) ..... 205

Appendix A Finite Element Method Using Hand Calculations . 207

Appendix B Analysis Types in AutodeskAlgorSimulation .. 215

Appendix C Linear Loads and Constraints .................. 229

Appendix D Material Model Options ........................ 249


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AutodeskAlgorSimulation 2011 Seminar Notes 3/15/2010 1

Introduction

Overview

This course will introduce you to the analysis products available within Autodesk Algor

Simulation. These capabilities include static stress with linear material models, heat transfer,

and linear dynamics analyses. The course will focus exclusively on models originating from

CAD solid modeling programs. You will learn the various meshing options available for

creating solid and plate elements. The available load and constraint options for each of the

covered analysis types will also be presented. You will learn how to evaluate the results of

the analyses and how to create presentations of the results, including images, animations and

HTML reports. This course is a prerequisite to the more advanced topics of Mechanic Event

Simulation (MES) and Computational Fluid Dynamics (CFD).

Software Installation, Services, and Support

Installing and Running AutodeskAlgorSimulation

The simulation software is distributed on DVDs with the exception of software for the Linux

platform, which is distributed on CDs. In addition, the software may be downloaded from the

Autodesk website. When you place the software DVD into a DVD-ROM drive, a launch

dialog having four options will appear. If you want to set up the software on a client

workstation, whether you will be using a license locked to a single computer or a network

license, press the "Install Products" button. If using a network license, you must already

have the license server software installed to a computer on the network. If you wish to create

pre-configured deployments for installing the product on multiple client workstations, choose

the "Create Deployments" command. If you want to set up the computer as a license serverto control the number of concurrent users through a network, or, if you wish to install optional

reporting tools, press the "Install Tools and Utilities"command. Finally, a fourth command

on the launch screen, "Read the Documentation," leads to a screen from which you can

access a ReadMe file and other installation and licensing guides.

During the product installation process, you will need to specify your name, the name of your

organization. You will also need to enter the product serial number and the product key.

Otherwise, you will be limited to a 30-day trial period. To customize the installation location

on your computer, the components to be installed, and/or to specify a network license server,

you will have to press the "Configuration"button that appears on one of the screens during

the installation process. Then, follow the prompts, provide the required information, and click

the "Configuration Complete"button to continue the installation process.

Any time after the installation, you will be able to start the software by using the available

shortcut found in the "Start" menu folder, "All Programs: Autodesk: Autodesk Algor

Simulation." The version number is included in the start menu folder name and shortcut.

The name of the shortcut will depend upon which package has been purchased ("Simulation,"

"Simulation MES," "Simulation CFD," or "Simulation Professional"). In the dialog

that appears when the program is launched, you will be able to open an existing model or

begin a new model. The simulation software will be used to create, analyze, and review the

results of an analysis within a single user interface, regardless of the analysis type.


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System Requirements

We recommend the following system specifications for a Microsoft Windows platform

running Autodesk Algor Simulation. These specifications will allow you to achieve the best

performance for large models and advanced analysis types.

32-Bit

Dual Core or Dual Processor Intel 64or AMD 64, 3 GHz or higher

64-Bit *

2 GB RAM or higher (3 GB for MESand CFD applications)

30 GB of free disk space or higher

256 MB or higher OpenGLaccelerated graphics card

DVD-ROM drive

Dual Core or Dual Processor Intel 64or AMD 64, 3 GHz or higher

8 GB RAM or higher

100 GB of free disk space or higher

512 MB or higher OpenGLaccelerated graphics card

DVD-ROM drive

Supported Operating Systems:

Microsoft Windows 7 (32-bit and 64-bit editions)

Microsoft Vista (32-bit and 64-bit editions)

Microsoft Windows Server 2003 and Windows Server 2008

Microsoft Windows XP (32-bit and 64-bit editions) Linux **

Other Requirements (All Platforms):

Mouse or pointing device

Sound card and speakers ***

Internet connection *** Web browser with Adobe Flash Player 10 (or higher) plug-in ***

* We recommend usage of a 64-bit version of the operating system to run large models of any

analysis type and for Mechanical Event Simulation, CFD, and Multiphysics analyses.

While a 32-bit machine can be configured for larger system memory sizes, architectural

issues of the operating system limit the benefit of the additional memory.

** Linux may be used as a platform for running the solution phase of the analysis only. It

may be used for a distributed processing (or clustering) platform. However, pre- and

post-processing is done in the graphical user interface, which must be installed and run

on a Microsoft Windows platform.

*** These requirements are due to the use of multimedia in our product line and theavailability of distance learning webcasts, software demos, and related media.

Minimum system requirements and additional recommendations for Linux platforms may be

found on the Autodesk website. To navigate to the Autodesk Algor Simulation web page,

access the HELP pull-down menu within the user interface, select the "Web Links"pull-out

menu, and choose the "Autodesk Algor Simulation"link.


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Introduction


Autodesk Algor Simulation Help

Autodesk Algor Simulation Help, often referred to as the Help files or users guide, contains

the following information:

Documentation for all of the model creation options within the user interface

Documentation for all of the Autodesk Algor Simulation analysis types Documentation for all of the result options available within the user interface Step-by-step examples that illustrate many modeling and analysis options

How to Access the Help Files

From the user interface, access the HELP pull-down menu and select the "Contents"command. The Autodesk Algor Simulation Help title page of will appear.

You can navigate through the user's guide via the table of contents to the left or by usingthe "Search"or "Index"tabs.

Features of the Help Files

Autodesk Algor Simulation Help is a set of compiled help files that are installed with thesoftware but are also accessible from the Autodesk website.

Hyperlinks and a table of contents make it easy to move quickly from topic to topic.

The Help window contains a standard Internet browser toolbar, so you can move forwardand backward and print with ease.

Figure I.1: Autodesk Algor Simulation Users Guide


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Introduction


Search the Help Files using Keywords

All of the pages in the Help files can be searched based on keywords.

The keywords are entered at the top of the "Search" tab on the left side of the UsersGuide screen. Topics that match the search criteria are listed below.

Keywords are used to search the Help files. You may use single or multiple keywords. Boolean operators (AND, OR, NEAR, and NOT) are available to enhance the search utility.

Also, phrases may be enclosed in quotes to search only for a specific series of words.

Subscription Center

Along with your Autodesk Algor Simulation software purchase, you have the option of

purchasing various levels of Subscription Center access and support. The Subscription Center is

accessible via the "key" icon near the right end of the program title bar and also via the

"Help: Web Links"menu.

Through the Subscription Center, you can download software updates, service packs, and add-

on applications. You can access training media, such as topical webcasts. Finally, you can also

submit technical support requests via the Subscription Center.

Web Links

Within the HELP pull-down menu of the Autodesk Algor Simulation user interface, there is a

"Web Links"pull-out menu. The following content can be accessed via the web links within

this menu:

Autodesk Algor Simulationproduct page Subscription Center Services and Supportinformation Discussion Group

Training course information Autodesk Labs where you may obtain free tools and explore developing technologies Manufacturing Community

Tutorials

Tutorials are available that demonstrate many of the capabilities of the Autodesk Algor

Simulation software. Each analysis is presented through step-by-step instructions with

illustrations to assist the user. The tutorials are accessed from the "Help: Tutorials"

command and the associated model files are in the "\Tutorials\Models"subdirectory within

the program installation folder. The tutorials will appear next to the user interface. You will

be able to follow the steps using the software without switching between the two windows.

Webcasts and Web Courses

Webcasts focus on the capabilities and features of the software, on new functionality, on

accuracy verification examples, and on interoperability with various CAD solid modeling

packages. These streaming media presentations are available for on-demand viewing from

the Subscription Center via your web browser. Similarly, web courses are also available for

on-demand viewing. Web courses are typically longer in duration than webcasts and focus on

more in-depth training regarding the effective usage of your simulation software. The topics

cover a wide variety of application scenarios.


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Introduction


For a list of available webcasts and web courses, follow the "Training"link from the home

page of the Subscription Center. Choose the "Autodesk Algor Simulation"product in the

"Browse the Catalog"list. This leads to the Autodesk Algor Simulation e-Learning page, in

which the available webcasts and web courses are listed according to topic.

How to Receive Technical Support

Technical support is reachable through several contact methods. The means you can use may

depend upon the level of support that was purchased. For example, customers with "Silver"

support must obtain their technical support from the reseller that sold them the software. "Gold"

subscription customers may obtain support directly from Autodesk.

Five ways to contact Technical Support:

Reseller: Obtain phone, fax, and/or e-mail information from your reseller.

Subscription Center: Access the Subscription Center from the link provided in the programinterface. Click the Tech Support link on the left side of the page

and then click on the "Request Support" link.

Autodesk Phone: (412) 967-2700 [or in USA/Canada: (800) 482-5467] Autodesk Fax: (412) 967-2781

Autodesk E-mail: [email protected]

When contacting Technical Support:

Have your contract number ready before contacting Technical Support.

Know the current version number of your software.

Have specific questions ready.

Remember, Technical Support personnel cannot perform, comment on, or makejudgments regarding the validity of engineering work.

Updates

The software is updated with new functionality on a continual basis. The following three

types of releases are provided:

1. A major version: Indicated by the four-digit year of the software release (based uponthe Autodesk fiscal year, not the calendar year)

2. A "subscription" version: Customers with a current maintenance subscription areeligible for additional releases that may be made available between major product version

releases. These are designated by the addition of the word "Subscription" after the major

version number.

3. A service pack: Incorporates minor improvements to a major or subscription release andis indicated by the letters "SP" and a service pack number after the major or subscription

version number.


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Introduction


How to Determine the Software Version

Access the HELP pull-down menu in the user interface and select the "About" command.

This dialog will display the version that you are using. In addition, the program title bar and

the splash screen that appears at each program launch will indicate the major version number

of the software. However, as with the start menu group name and program shortcut, it will

not indicate the subscription and service pack variants.

How to Obtain an Update

Update notifications are provided via the "Communication Center" within the user interface.

The Communication Center icon is located at the right end of the program window title bar.

Whenever new information is available, the state of the Communication Center icon changes.

The Communication Center provides up-to-date product support information, software

patches, subscription announcements, articles, and other product information through a

connection to the Internet. Users may specify how frequently the Live Update information

will be polledon-demand, daily, weekly, or monthly. When a program update notification

is received, the user will be given the option of downloading and installing it.

Background of FEA

What is Finite Element Analysis?

Finite element analysis (FEA) is a computerized method for predicting how a real-world

object will react to forces, heat, vibration, etc. in terms of whether it will break, wear out or

function according to design. It is called "analysis", but in the product design cycle it is used

to predict what will happen when the product is used.

The finite element method works by breaking a real object down into a large number (1,000s

or 100,000s) of elements (imagine little cubes). The behavior of each element, which isregular in shape, is readily predicted by a set of mathematical equations. The computer then

adds up all the individual behaviors to predict the behavior of the actual object.

The "finite" in finite element analysis comes from the idea that there are a finite number of

elements in the model. The structure is discretized and is not based on a continuous solution.

As in any discrete method, the finer the increments or elements, the more precise the solution.

Previously, engineers employed integral and differential calculus, which broke objects down

into an infinite number of elements.

The finite element method is employed to predict the behavior of objects with respect to

virtually all physical phenomena:

Mechanical stress (stress analysis) Mechanical vibration (dynamics) Heat transfer - conduction, convection, radiation Fluid flow - both liquid and gaseous fluids Electrostatic or MEMS (Micro Electro Mechanical Systems)


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Introduction


Basic FEA Concepts

Nodes and Elements

A node is a coordinate location in space where the degrees of freedom (DOFs) are defined.

The DOFs of a node represent the possible movements of this point due to the loading of the

structure. The DOFs also represent which forces and moments are transferred from oneelement to the next. Also, deflection and stress results are usually given at the nodes.

An element is a mathematical relation that defines how the DOFs of one node relate to the next.

Elements can be lines (beams or trusses), 2-D areas, 3-D areas (plates) or solids (bricks and

tetrahedra). The mathematical relation also defines how the deflections create strains and stresses.

Degrees of Freedom

The degrees of freedom at a node characterize the response and represent the relativepossible motion of a node.

The type of element being used will characterize which DOFs a node will require.

Some analysis types have only one DOF at a node. An example of this is temperature ina thermal analysis.

A structural beam element, on the other hand, would have all of the DOFs shown in

Figure I.2. "T" represents translational movement and "R" represents rotational movement

about the X, Y and Z axis directions, resulting in a maximum of six degrees of freedom.

Figure I.2: Degrees of Freedom of a Node

Element Connectivity Conventional Bonding

Elements can only communicate to one another via common nodes. In the left half of

Figure I.3, forces will not be transferred between the elements. Elements must have common

nodes to transfer loads from one to the next, such as in the right half of Figure I.3.

Figure I.3: Communication through Common Nodes

No Communication Communication

Between the Elements Between the Elements


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Introduction


Element Connectivity "Smart Bonding"

With the introduction of "Smart Bonding" it is now possible to connect adjacent parts to each

other without having to match the meshes (i.e., common nodes at part boundaries are no

longer mandatory). This feature is available for both CAD and hand-built models and is

applicable to the following analysis types:

Static Stress with Linear Material Models Natural Frequency (Modal) Transient Stress (Direct Integration)

Figure I.4, is a pictorial example of two adjacent parts that may be connected via smart

bonding. Smart bonding is disabled by default for both new and legacy models (that is, those

created prior to implementation of the smart bonding feature). The option may be changed

within the "Contact" tab of the Analysis Parameters dialog. Note that where nodal

coordinates fall within the default or user-specified tolerance of each other, they will be

matched in the conventional manner. Other nodes along the bonded surfaces or edges those

at a relative distance greater than the tolerance will be connected by means of multipoint

constraint equations (MPCs). Also note that the "Use virtual imprinting"option within the

"Model" dialog of the mesh settings options will minimize the likelihood that smart bondingwill be needed or will occur for CAD-based assemblies. This option attempts to imprint

smaller parts on larger parts where they meet, forcing them to have identical meshes.

Figure I.4: Connection via "Smart Bonding"

Types of Elements

The actual supported and calculated DOFs are dependent upon the type of element being

used. A node with translational DOFs can move in the corresponding directions and can

transmit/resist the corresponding forces. A node with rotational DOFs can rotate about the

corresponding axes and can transmit/resist the corresponding moments.

Briefly, the general element types are as follows (more details will be given in later chapters and

in theAdvanced Modeling Supplement):

Line elements: A line connecting 2 nodes (such as beams, trusses, springs, thermalrods, and others).

2-D elements: YZ-planar elements that are triangular or quadrilateral (3 or 4 linesenclosing an area).

3-D plates or shells: Planar or nearly planar elements in 3-D space. Each must betriangular or quadrilateral and they represent a thin part with a specified thickness.

Brick (solid) elements: Must be enclosed volumes with 4, 5, or 6 faces (triangularand/or quadrilateral) and with 4, 5, 6 or 8 corner nodes.


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Introduction


DOFs for element types:

Truss: Translation in X, Y and Z. Beam: Both translation and rotation in X, Y and Z. 2-D: Translation in Y and Z. Plate: Five degrees of freedom out-of-plane rotation is not considered.

Brick: Translation in X, Y and Z.

How Does Autodesk Algor Simulation Work?

The software transforms an engineering model with an infinite number of unknowns intoa finite model.

This is an idealized mathematical model.

The model is defined by nodes, elements, loads and constraints.

The user interface can be effectively used for the design, analysis and evaluation phases of atypical design process.

The simulation software can be extremely useful during the initial concept and design phase toidentify areas that can be improved.

The simulation software can also be used to quickly evaluate a concept, saving time andengineering resources.

This does not necessarily replace the testing needed to evaluate a final design; howeverthe goal is to minimize the prototype and testing stages of design.

The General Flow of an Analysis in Autodesk Algor Simulation

Create a Mesh

Start the simulation program Open your model in the FEA Editor environment

Select the analysis type Create your mesh

Define the FEA Data

Assign the loads and constraints Define the material Define the analysis parameters

Run the Analysis

Review and Present Results

Review the desired result types Save images and animations Create presentations and HTML reports


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Introduction


Stress and Strain Review

Equations Used in the Solution

A complex system can be broken into a finite number of regions (elements), each of which

follows the equations below:

L

AEF

dx

E

A

F

=

=

=

=

L

0

where, = stress, F = force, A = area

= strain, E = modulus of elasticity

= displacement, L = length

When the interaction of each region with its neighbor (through the nodes) is considered, a

system of equations is developed:

{f} = [K] {x}

nown Unknown

where, {f} is the vector that represents all of the applied loads. [K] is the assemblage

of all of the individual element stiffnesses (AE/L) and {x} is the vector that

represents the displacements.

Since the applied load vector and element stiffnesses are known from the user input, the

equation can be solved using matrix algebra by rearranging the equation as follows for the

displacement vector:

{ } [ ] { }fKx 1=

Strains are computed based on the classical differential equations previously discussed. Stress canthen be obtained from the strains using Hookes Law. These basic equations do not require the use

of a computer to solve. However, a computer is needed when complexity is added, such as:

1. Geometric complexity (makes the elasticity equation impossible to solve).

2. Variation in material properties throughout the body.

3. Multiple load cases and complex or combined loading.

4. Dynamics.

5. Large systems (require many equations to solve).


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In practice, the direct inversion is extremely difficult and sometimes unstable. In FEA,

matrices can be 50,000 x 50,000 or larger. As a result, other solution methods for this linear

equation have been developed. All of these methods use the basic principles of a

mathematical method called Gaussian Elimination. The details of this method will not be

discussed here, but may be obtained from any numerical programming text.

Since differentiation cannot be performed directly on the computer, approximation techniques

are used to determine the strain in the model. Since an approximation technique is used for

the strains, the finer the mesh, the better the approximation of the strain. For a linear static

analysis, stress has a linear relation to strain. Therefore, the stresses will have the same

accuracy as the strains.

For more complex analyses, more terms are needed. The equation below is needed to

represent a true dynamic analysis:

{ } [ ]{ } [ ]{ } [ ]{ }xKxcxmf ++= where the additional matrices and vectors are,

m = mass, x = acceleration (second derivative of displacement versus time)c = damping, x = velocity (first derivative of displacement versus time)

Limits of Static Stress with Linear Material Models

Deformations are small

Strains and rotations are small

Changes in stiffness through the model are small

Changes in boundary conditions are small

Changes in loading direction with deformations are small

Material remains in the linear elastic range

Mechanical Event Simulation (MES) Overcomes Limitations

MES supports:

Large deformations

Changing boundary conditions

Loads moving as the model moves or deforms

Nonlinear material behavior

Time-dependent loading

Large-scale motion

Event visualization capabilities:

Viewing results with respect to time using the Results environment

Animation tools


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Introduction


MES simulates:

Motion

Impact

Real-time observation of deformations, stresses and strains

Failure due to the following: material yielding, local and structural buckling, permanentdeformations - residual stress

In order to perform MES, one of the following Autodesk Algor products is requiredAutodesk

Algor Simulation MESor Autodesk Algor Simulation Professional. This analysis type is not

available within the standard Simulationor Simulation CFDsoftware packages.

For information and training regarding MES, refer to the Autodesk Algor Simulation MES

training course.

Hand-Calculated Example

Refer to Appendix A for an example of displacement and stress results for a simple truss

structure. A theoretical solution using fundamental equations is presented. In addition, ahand-calculated solution based on the finite element method is presented and its results

compared with those obtained by the FEA software.


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Introduction


Heat Transfer Review

Equations Used in the Solution

Heat transfer, as applied to FEA, is actually a conduction problem. The heat loads are

boundary conditions. The primary results are a temperature profile and the heat flux through

the body of the structure.

Conduction is the flow of heat in the body of the structure. This is what is being solved in an

FEA problem. The properties of conduction are controlled by the part definition. Only the

thermal conductivity (k) is needed for a steady-state analysis. For a transient analysis, the

mass density and specific heat will also be required. The governing equation is:

=

L

TkAq

where: k = Thermal conductivityA = Area

T = Change in temperatureL = Length

The two most common loads for a thermal analysis are convection and radiation loads. These

loads are applied to a surface. The equation for the heat flow due to convection is:

( )= TThAq s

where: h = Convection coefficient

A = Area

Ts = Temperature of the surfaceT= Ambient temperature

The equation for the heat flow due to radiation is:

( ) )44.. bTTFVAq = where: = Emissivity which describes the surface finish for gray bodies. (If = 1.0, it

is a true blackbody.)

= Stefan-Boltzmann constant for radiation

A = Area

V.F. = View factor from the surface to the infinite source

T= Ambient temperature (in units of absolute temperature)

Tb = Temperature of the node (in units of absolute temperature)


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Linear Dynamics Review

Equation for Dynamic Analyses

The basic equation of dynamics is:

[m]{a}+[c]{v}+[k]{x}=0

where:

[m] = the mass matrix

{a} = the acceleration vector

[c] = the damping constant matrix

{v} = the velocity vector

[k] = the stiffness matrix

{x} = the displacement vector

A natural frequency analysis provides the natural vibration frequencies of a part or assemblybased on a linear eigenvalue solution. Because the above equation is solved in this linear

solution, only mass and stiffness are taken into account. No damping is used. In addition,

loads are ignored. As a result, actual displacement output is meaningless except to define the

shape of the natural frequency mode. Note that loads are taken into account for a natural

frequency with load stiffening analysis, assuming the loads produce membrane stresses that

affect the stiffness of the structure.

Constraints have a very significant effect on the solution. When no boundary conditions or

insufficient boundary conditions are used, rigid-body movement or modes will be found.

Unlike a static solution, this is acceptable in a modal analysis.


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Using AutodeskAlgorSimulation

Chapter Objectives

Introduction to the user interface

o Toolbarso Keyboardo Mouseo ViewCube and other view controls

Complete an example of using Autodesk Algor Simulation

o Overview of how to open a CAD solid model and creating a mesho Overview of adding loads and constraints to a modelo Overview of defining material propertieso Overview of performing an analysiso Overview of reviewing resultso Overview of generating a report

Navigating the User Interface

In this section, we will introduce you to the Autodesk Algor Simulation user interface. This

interface is the same for each of the available packages, including the foundational AlgorSimulation product and the Algor Simulation CFD, MES, and Professional products. The

only difference will be with regard to which advanced features or capabilities are enabled.

We will begin with an overview of the major components of the graphical user interface.

Then we will discuss the toolbars, keyboard, mouse, ViewCube, and additional view controls.

Please note that the behavior of the keyboard, mouse and ViewCube as discussed within this

manual are based on the default program settings for a clean installation of the product.

Many of the features to be discussed are customizable via tabs and settings within the

"Options" dialog, reachable via the "Tools: Options"pull-down menu command.

Figure 1.1 on the next page, along with the legend that follows it, introduce the major

components of the user interface. This manual is based on Autodesk Algor Simulation 2011.

Users of other versions may encounter differences between their version and the interfacedescribed herein.

Chapter

1


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Figure 1.1: Autodesk Algor Simulation User Interface

Interface Legend:

A. Title Bar: The title bar displays the program name and version as well as providing links to the

Autodesk Subscription Center and Communication Center.

B. Menu Bar: The menu bar is located just below the title bar and contains the pull-down menus.

C. Toolbars: The toolbars provide the user with quick access to many commands.

D. Tree View: The tree view has unique contents for each environment of the user interface. For the

FEA Editor, it shows the parts list and the units, various properties, and loads that will be used for

the analysis. In the Results environment, you will see a list of results presentations and other post-

processing-specific content. The components of the analysis report will be listed in the tree view

within the Report environment.

E. ViewCube and Additional View Controls: These tools are used to manipulate the model display

position, rotation, zoom, display pivot point, and so on. There is also an optional Compassfeature

that can be activated, providing a compass heading ring around the base of the ViewCube.

F. Display Area: The display area is where the modeling activity takes place. The title bar of thewindow displays the current environment and the model name. The FEA Editor environment is used to

create the model, add the loads and constraints and perform the analysis. The Results environment is

used to view results and to create images, graphs, and animations. The Report environment will be

used to produce a formal report of the analysis, including desired results presentations.

G. Miniaxis and Scale Ruler: The miniaxis shows your viewpoint with respect to the three-

dimensional working area. The scale ruler gives you a sense of the model size,

H. Status Bar: The status bar displays important messages.


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Toolbars

Autodesk Algor Simulation accesses program functions through pull-down menus, context

menus, and toolbars. The available toolbars and menus vary for each program environment

(FEA Editor, Results, and Report). By default, the toolbars are positioned at the top of the

screen, just under the pull-down menus. As is true for the menus, commands are logically

grouped into a number of different toolbars. For example, one toolbar includes predefinedview orientations, another includes various selection tools, still another includes structured

meshing tools, and so on. These may be displayed, hidden, or repositioned as desired.

Most of the toolbars and pull-down menus will not appear until an existing model is opened

or a new model is created. To see the toolbars of the FEA Editor at this time, start the

program. Dismiss the "What's New" screen if it appears, select the "New"icon in the initial

dialog ("Open" / "New"), and click the "New"button. Navigate to a working folder, type in

the name of your choice in the "File name:"field, and click the "Save"button.

Displaying or Hiding Specific Toolbars

To display or hide toolbars or to adjust the icon size or style, access the TOOLS pull-down

menu and select the "View Toolbars..." command. To display another toolbar activate thecheckbox for that toolbar. Deactivate the checkbox for each toolbar that you prefer to hide.

Additional checkboxes are provided for the toolbar size and style options. Press the "Close"

button to exit the "Toolbars"screen.

Docking Toolbars

Toolbars can be docked on the top, bottom and/or sides of the display area. To dock a

toolbar, first click on the title bar and drag it toward one of the edges of the display area.

Once you reach the edge, the shape will change to signify that you are at a location where the

toolbar may be docked. Release the mouse and the toolbar will dock at the location of the

mouse. That is, it will snap to the docked position and the title bar will disappear. This is

illustrated in the following images.

Figure 1.2: Steps to Dock a Toolbar


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Using the Keyboard and Mouse

The keyboard and mouse will both be used to operate within the user interface. The keyboard

will be used to enter the required data for loads, constraints, material properties, and so on. It

will also be used to modify the behavior of particular mouse operations. That is, certain

keyboard keys, when held down, will change the behavior of the mouse.

The software supports a number of different mouse configurations. This document assumes that

the default template for a new installation is in effect. However, user settings, or those retained

from a prior Autodesk Algor Simulation installation, may cause the behavior to differ from that

described herein. To ensure that your mouse actions follow the descriptions in this book, access

the "Tools: Options: Mouse Options"dialog and choose the "Algor Simulation"template.

The left mouse button will be used to select items. How items are selected will depend upon

the selection mode chosen in the "Selection: Shape"pull-out menu or toolbar. The type of

objects that are selected (such as lines, vertices, surfaces, parts, edges, or elements) will

depend upon the selection mode chosen in the "Selection: Select"pull-out menu or toolbar.

Holding down the key while left-clicking an object will toggle the selection state of

the clicked object. That is, unselected objects will be added to the selection set andpreviously selected items will be removed from the selection set. Holding down the

key while left-clicking will only add clicked objects to the selection set (this will have no

effect on already selected items). Finally, holding both and while left-

clicking will only remove clicked objects from the selection set (this will have no effect on

items that are not already part of the current selection set).

Pressing the right mouse button with the cursor hovering over items in the tree view will

access a context menu with commands relevant to the item under the cursor. When items are

currently selected, either within the tree view or display area, the right-click context menu

will display commands and options that are specifically relevant to the selected items. For

example, if a surface is selected, only surface-based commands will appear in the context

menu. You may right-click anywhere in the display area when items are selected to access

the context menu. However, to access the context menu within the tree view area, you must

right-click with the cursor positioned on one of the selected headings.

If a mouse has a wheel, rolling the wheel will zoom in or out on the model. Holding down the

middle mouse button or wheel and dragging the mouse will rotate the model. Pressing the

key while holding the middle button and dragging the mouse will pan the model,

moving it within the display area. Pressing the key while dragging the mouse with

the middle button down will zoom in and out, making the model larger as the mouse is moved

upward and smaller as it is moved downward. You will likely find the use of the middle

mouse button and wheel to be more convenient than choosing a command like "Rotate"or

"Pan,"clicking and dragging the mouse, and then pressing to exit the command.

Finally, the X, Y, or Zkey on the keyboard may be held down while dragging the mouse with

the middle button held down. Doing so will rotate the model, as before, but constraining the

rotation to be only about the corresponding X, Y, or Z global axis direction. You may alsouse the left and right cursor keys on the keyboard while holding down X, Y, or Z to rotate

about these axes in fixed increments (15 degrees by default). The rotation increment is

customizable via the "Tools: Options: Graphics: Miscellaneous"dialog.


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Introduction to the ViewCube

As is true for the mouse, the software also supports a number of different view configurations.

This document assumes that the default view options template and view navigation settings

for a new installation are in effect. However, user settings, or settings retained from a prior

Autodesk Algor Simulation installation, may cause the view orientations and behavior to

differ from those described throughout this document. To ensure that your view commandsfollow the descriptions in this book, access the "Tools: Options: Views Options"dialog and

choose the "Algor Simulation"template.

Next, access the "Graphics"tab of the same "Options" dialog, select "Navigation Tools"from

the items listed on the left side of the dialog, and click on the "View Cube"button. Click the

"Restore Defaults"button followed by "OK"to exit the "ViewCube Properties" dialog.

Finally, click the "Steering Wheel"button. Click the "Restore Defaults"button followed by

"OK"to exit the "SteeringWheels Properties" dialog. Click "OK"to exit the "Options" dialog.

Users of other Autodesk products, such as AutoCAD or Autodesk Inventor will likely

already be familiar with the ViewCube and associated additional view controls. If so, feel

free to skip to the Steel Yoke Example that begins on page22.

The ViewCube will be located in the upper right corner of the display by default but may be

relocated. The appearance will change depending upon whether the view is aligned with a

global plane and whether the cursor is near the cube or not. The ViewCube, in its various

appearances, is shown in Figure 1.3.

Figure 1.3: ViewCube Appearance

The six standard view names, as labeled on the cube faces, are the Top, Bottom, Front, Back,

Left, and Right. These may be selected by clicking near visible face names on the cube, as

shown in Figure 1.3 (b) or by clicking the triangular arrows pointing towards the adjacent faces,

as shown in Figure 1.3 (c), which shows the cursor pointing to the arrow for the Bottom view.

In addition, there are clickable zones at each corner and along each edge of the ViewCube.

Clicking on a corner will produce an isometric view in which that particular corner is

positioned near the center and towards you. Clicking an edge will produce an oblique view,

rotated 45 degrees, half-way between the views represented by the two adjacent faces.When the cursor is near the ViewCube, a "Home"icon will appear above it and to the left,

providing easy access to the home view. This is an isometric view having the corner between

the Front, Right, and Top Faces centrally positioned and towards you by default. The home

view may be redefined by right-clicking the Home icon and choosing the "Set Current View

as Home"command while viewing the model positioned as desired.

When one of the six standard views is active and the cursor is near the ViewCube, two curved

arrows will appear above and to the right of the cube, as seen in Figure 1.3 (c). These are

(a) Cursor not near the

ViewCube

(b) Cursor on ViewCube

(view not aligned to a

standard face)

(c) Cursor on ViewCube

(standard face view)


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used to rotate the model to one of the four possible variants of the particular standard view.

Each click of an arrow will rotate the model 90 degrees in the selected direction.

When the face being viewed is changed via the ViewCube, the model may move to the

selected view in the manner that requires the least amount of motion. For example, say we

are first looking at the Right view, with the word "Right" positioned upright (that is in the

normal reading position). Now, if we click the downward arrow above the cube, the model

will rotate 90 degrees to reveal the top face. The Top view will be rotated 90 degrees

clockwise from the upright orientation (that is, the word "Top" will read in the vertically

downward direction). Activating the "Keep scene upright" option will cause the Front,

Back, Left, and Right views to automatically be oriented in the upright position (Top above,

Bottom below) when changing to any of these views. You may, however, rotate the view

after initial selection, if desired. Go to "Tools: Options: Graphics: Navigation Tools:

View Cube"to locate the "Keep scene upright"setting. It is activated by default.

The point of this discussion is that whenever a new face is selected using the ViewCube, the

resultant view rotation may differ, depending upon the prior position of the model. If the resultant

orientation is not what is desired, simply click one of the curved arrows to rotate the view.

Additional View Controls

Immediately below the ViewCube is a pallet of additional view controls. This

consists of seven tools, each of which may be individually enabled or disabled.

All are on by default. Figure 1.4 shows the view control pallet.

From top to bottom, the seven tools are as follows:

SteeringWheels Pan Zoom Orbit Center

Previous View Next View

Each of these icons, except for the Previous and Next commands, function as a

toggleclicking it once to activate a command and again to deactivate it.

Several of these tools, such as Pan, Previous, and Next are self-explanatory.

The "Zoom" tool includes a fly-out menu allowing the choice of one of four different

zooming modesZoom, Zoom (Fit All), Zoom (Selected), and Zoom (Window). The first of

these cause the model to become larger as the cursor is moved upward in the display area and

smaller when it is moved downward. The Fit (All) mode encloses the extents of the whole

model. After selecting objects in the display area, the Zoom (Selected) tool fits the selected

items into the display area. Finally, after selecting the Zoom (Window) tool, you click and

drag the mouse to draw a window define the area you wish to expand to fill the display area.

The "Orbit" tool has two variants, selectable via a fly-out menuOrbit, and Orbit

(Constrained). The former allows the model to be rotated freely in any direction. The

Constrained option causes the model to rotate only about the global Z-axis, similar to pressing

the Z key while dragging the mouse with the middle button depressed.

The "Center"tool is used to center a point on the model within the display area. Click with

the mouse to specify the desired center point after selecting the Center command. This point

also becomes the display pivot point, about which the model pivots when being rotated.

Figure1.4:AdditionalViewC

ontrolsPallet


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The "SteeringWheels" tool is customizable and, in its default setting, produces the Full

Navigation Wheel shown in Figure 1.5. The full navigation wheel floats above the model

view, following the cursor position. It provides an additional access method for several

functions found elsewhere on the view tools pallet as well as a few additional functions.

Figure 1.5: Full Navigation Wheel

The "Rewind"button on the navigation wheel presents a timeline of thumbnails representing

various views that have been used during the modeling session. Simply release the mouse

button with the cursor positioned at the thumbnail representing the view to which you wish to

jump. This is more convenient than pressing the previous or next view buttons multiple times.

For additional information concerning these view controls, consult the User's Guide.

Legacy View Controls in Autodesk Algor Simulation

Traditional view controls and options are also provided via the pull-down menus and toolbars

at the top of the user interface window. Options for displaying or hiding the mesh or model

shading may be found here as well as eight pre-defined, standard view orientations. The

orientations will depend upon the currently active views options template (previously

discussed in the "Introduction to the ViewCube"section of this chapter).

There is also a "User-defined Views" dialog that may be used to save, modify, or restore

custom views. Additional capabilities include a local zoom feature and display toggles for thescale ruler, miniaxis, and perspective mode.

The "Local Zoom" feature displays a small rectangle that represents the area to be

magnified. A larger rectangle shows an overlay of the magnified region. You may click on

and drag the local zoom window to position it anywhere on the model within the display area.

The size of the local zoom area and magnified overlay and also the zoom level can be

customized via the "Tools: Options: Graphics: Local Zoom"dialog.

For additional information concerning the legacy view controls, consult the User's Guide.


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Steel Yoke Example

This example is an introduction to static stress analysis with linear material models. The

example will give step-by-step instructions to create a mesh and analyze a three-dimensional

(3-D) model of a steel yoke under an applied force. There are three sections:

Setting up the model Open the model in the FEA Editor environment and create the mesh

on the model. Add the necessary forces and boundary conditions and define the model

parameters. Visually check the model for errors with the Results environment.

Analyzing the model Analyze the model using the static stress with linear material models

processor.

Reviewing the results View the displacements and stresses graphically using the Results

environment.

Use the CAD solid model, yoke.step, located in the "Chapter 1 Example Model\Input File"

folder in the class directory (or extracted to your computer from the solutions archive) to

create a simple model of the steel yoke shown in Figure 1.6. The right half of the small hole

will be fixed. A force of 800 pounds will be applied to the left half of the large hole and

acting towards the left, as shown in the figure. The yoke is made of Steel (ASTM-A36).

Analyze the model to determine the displacements and stresses.

Figure 1.6: Steel Yoke Model

Opening and Meshing the Model

The FEA Editor environment is used to create a mesh for all solid models. You can open

CAD solid models from any of the CAD solid modelers that Autodesk Algor Simulation

supports. You can also open models of any of the universal CAD formats that are supported.

"Start: All Programs:

Autodesk: Autodesk Algor

Simulation: Autodesk Algor

Simulation"

Press the Windows "Start"button and access the "All

Programs"pull-out menu. Select the "Autodesk"folder

and then the "Autodesk Algor Simulation"pull-out menu.

Choose the "Autodesk Algor Simulation"command.

"Open" Click on the "Open"icon at the left side of the dialog.

"STEP (*.stp, *.ste, *.step)"Select the "STEP (*.stp, *.ste, *.step)" option in the CAD

Files section of the"Files of type:"drop-down box.

"Yoke.step"Select the file "Yoke.step"in the "Chapter 1 Example

Model \Input File"directory.

"Open" Press the "Open"button.


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"Use STEP file units"

"OK"

A "Select Length Units" dialog will appear. Choose "Use

STEP file units"from the pull-down menu and click the

"OK"button.

"Linear: Static Stress with

Linear Material Models"

"OK"

A dialog will appear asking you to choose the analysis type

for the model. From the pull-out menu, choose "Linear:

Static Stress with Linear Material Models"and press the

"OK"button.

The model will appear in the FEA Editor environment.

"Mesh: Model Mesh

Settings"

Access the MESH pull-down menu and select the "Model

Mesh Settings"command.

"Mesh model"Press the "Mesh model"button to create a mesh with the

default options.

"No"Press the "No"button when asked if you want to review the

meshing results.

"View: Rotate"Access the VIEW pull-down menu and choose the "Rotate"

command.

Mouse

Click and drag the mouse to rotate the model and inspect the

mesh all around it. This mesh appears to be acceptable.When done inspecting the mesh, position the model so that

you can see the inside of the small hole as shown in

Figure 1.7. These surfaces will be constrained.

Press to exit the rotate command.

Figure 1.7: Yoke Rotated to Select Constrained Surfaces

Setting up the Model

The FEA Editor environment is also used to specify all of the element and analysis parameters

for your model and to apply the loads and constraints. When you initially come into the FEA

Editor environment with the yoke model, you will notice a red X on certain headings in the

tree view. This signifies that this data has not yet been specified. You will need to eliminate

all of the red Xs before analyzing the model. Since you have created a solid mesh, the"Element Type"heading in the tree view is already set to "Brick"and the default "Element

Definition"parameters have been accepted.

Adding Constraints

Constraints describe how a finite element model is tied down in space. If an object is welded

down so that it can neither translate nor rotate, the object is fully constrained.


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"Selection: Shape: Point"

Access the SELECTION pull-down menu and select the

"Shape"pull-out menu. Select the "Point"command. This

will allow you to select objects by clicking directly on them.

"Selection: Select: Surfaces"

Access the SELECTION pull-down menu and choose the

"Select"pull-out menu. Select the "Surfaces"command.

This will allow you to select surfaces.

Mouse Click one of the surfaces on the right side of the small holeas oriented in Figure 1.7.

MouseHolding down the key, click on the other surface on

the right side of the small hole.

Mouse Right-click in the display area.

"Add: Surface Boundary

Conditions"

Select the "Add"pull-out menu and select the"Surface

Boundary Conditions"command. The dialog shown in

Figure 1.8 will appear.

Figure 1.8: Surface Boundary Condition Dialog

"Fixed"

Press the "Fixed"button. Note that all 6 of the checkboxes

in the "Constrained DOFs"section to the left are

activated. This means that the nodes on this surface will be

totally constrained.

"OK"

Press the "OK"button to apply these boundary conditions.

Now there will be green triangles on the nodes of the

surface that was selected. This signifies a fully constrained

boundary condition.

Adding Forces to the Model

In this section, you will add the 800 lb force in the X direction to the large hole.

Mouse

Click and drag using the middle mouse button to rotate the

model. Position it so that you can see the surfaces of the

large hole where the load is to be applied (that is, the two

quarter surfaces at the left side of the hole).

MouseClick on one of the surfaces on the left interior of the large

hole to select it.

MouseHolding down the key, click on the other surface on

the left side of the large hole.


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Mouse Right-click in the display area.

"Add: Surface Forces"

Select the "Add"pull-out menu and select the"Surface

Forces"command. The dialog shown in Figure 1.9 will

appear.

Figure 1.9: Surface Forces Dialog

-400

Type "-400"in the "Magnitude"field to add two forces of

400 pounds each in the negative X direction to the surfaces.

This force will be evenly distributed across each surface.They will combine to produce the desired 800 pound load.

"X"Select the "X"radio button in the "Direction"section to

add surface forces in the X direction.

"OK"

Press the "OK"button to apply these surface forces. Now

there will be green arrows on the surfaces that were

selected. They are pointed in the negative X direction.

"View: Orientation: Top

View"

Access the VIEW pull-down menu and select the

"Orientation"pull-out menu. Select the "Top View"

command. The model should now look like Figure 1.10.

Figure 1.10: Yoke after Boundary Conditions and Loads are Applied


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Assigning the Parameters

Once the model has been constructed and the loads and constraints have been applied, use the

FEA Editor environment to specify material properties.

Mouse Right-click on the "Material"heading for Part 1.

"Modify Material"Select the "Modify Material"command. The

"Element Material Selection"dialog will appear.

"Steel (ASTM-A36)"Highlight the "Steel (ASTM-A36)"item from the list of

available materials as shown in Figure 1.11.

Figure 1.11: Element Material Selection Dialog

"Edit Properties"Press the "Edit Properties"button to view the material

properties associated with this steel.

"OK"Press the "OK"button to exit the "Element Material

Specification"dialog.

"OK"Press the "OK"button to accept the information entered in

the "Element Material Selection"dialog for Part 1.

"Analysis: Check Model"

Access the ANALYSIS pull-down menu and select the

"Check Model"command to review elements, geometry

and loads in the Results environment before running theanalysis.

"Tools: FEA Editor"

Once you approve the model, access the TOOLS pull-down

menu and select the "FEA Editor" command to move back

to the FEA Editor environment to run the analysis.

"View: Orientation: Isometric

View"

Access the VIEW pull-down menu and select the

"Orientation"pull-out menu. Select the "Isometric

View" command.


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Algor

Simulation


Analyzing the Model

"Analysis: Perform

Analysis"

Access the ANALYSIS pull-down men

autodesk algor simulation_2011

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