FACULTY OF CHEMICAL & ENERGY ENGINEERING

FLUID MECHANICS LABORATORY

GUIDE TO LABORATORY WORK, SAFETY AND REPORTS

Prepared by: Dr Umi Aisah AsliSenior Lecturer,

Faculty Of Chemical & Energy Engineering,UTM.

1.0 Guide to Laboratory work

1.1 Course Description

The aim of this laboratory course is for students to conduct experiment in conjunction with Fluid Mechanics course. There are a total 9 experiments for this laboratory where two of them (Bourdoun Tube pressure gauge and Toricelli’s Law), students needs to construct and setup by their own based on the fundamental knowledge and literature finding. Other experiments include the operation of flow measurement equipment (Ventruri nozzle, pitot tube, orifice and nozzle), flow through a piping system to determine major and minor loses. The lab runs closely with the lectures’ observation in such a way that experiments support the text covered in the class room.

1.2 Required Texts and Materials

For this laboratory, students are strongly encourage to refer the main text book used for Fluid Mechanics subject, that is

Yunus A. Cengel & John M. Cimbala. Fluid Mechanics: Fundamentals and Applications, London: McGraw Hill.

All manual lab and guides will be uploaded in the e-learning. Students are required to study the experiment before enter to the lab. You are expected to be able to operate all equipment with minimal supervision. Note that technicians and supervisors will not demonstrate the experiment for students during the lab is running. However, you can ask questions whenever you in doubts. Also, note that, you will be observed and evaluated during the whole process each experiment.

The details for evaluation scheme, please refer to the Course Learning Outline (CLO) document. You can download the CLO from e-learning.

2.0 Safety Guide

All students are COMPULSORY to follow all safety regulation in the Fluid Mechanics laboratory. Note that, everyone in the lab is responsible for their own safety and the safety of others.

Personal and general laboratory safetyi) Lab coat must be worn in the lab area. You are advised to wear suitable

clothing for your own comfort and safety while doing the experiment in the lab.

ii) Closed toes and heel must be worn in the lab. Students are not allowed to wear slippers/sandal or high heels.

iii) Never eat, drink, or smoke while working in the laboratory.

iv) If there is an event of equipment failure while being used, report it immediately to the lab assistant or lecturer. Do not try to fix the problem yourself because you could harm yourself and others.

v) Do not forget to clean up your work area before leaving.

Emergency responsei) All people in the lab are required to evacuate the building and run to assembly

point if the fire alarm sounds.

3.0 Lab report

The lab report should be typed and submitted ONE week after the experiment has been done.

The lab report SHOULD NOT MORE THAN 5 PAGES. The lab report should have sections for experiment tittle and dates, group names,

summary, result and discussion (based on questions on the lab manual) and conclusion. You should mentioned references if any.

Sample of report as attached.

FLUID MECHANICS LABORATORY REPORT

Title : HYDROSTATIC PRESSUREDate of experiment : 6/9/2017 (Wednesday: 9 to 12 pm)Lecturer’s name : Dr Mahadhir MohamadSection : 01Group Number : 01Group member : 1. Ashraf Ali (Group leader)

2. Balakrishnan

3. Lim Swee Ping 4. Nur Aishah

SummaryThe objective of this lab is to determine the hydrostatic thrust acting on a plane surface immersed in water when the surface is partially submerged or fully submerged. Then, to determine the experimental center of pressure and the theoretical center of pressure for each of the trials performed. The procedure for this lab was performed following lab manual for ME-495 Laboratory Exercise – Number 7. The first part of this lab test was completed by adding mass to the balancing arm with the mass hanger in 50 gram increments until the tank is full. Water was then added to the tank to level the balancing arm by increasing the force on the plane surface. The height of the water measurements were recorded along with the added mass. The second part of this lab was completed by starting with a full tank and removing mass. The height of the water and added mass were recorded as in the first part of the lab.

Result and DiscussionAnswer for Question 1From the data collected the hydrostatic pressure and distance to the centre of pressure can be calculated for both the partially submerged and fully submerged plane surface. The graphs is shown in Figure 1 and 2.

Figure 1 Result for Partially Submerged

Figure 2 Result for Fully Submerged

Question 2Once the data collection was done the theoretical hydrostatic pressure and distance to the centre of pressure can be calculated. From this, one could compare the theoretical values to the actual values measured. The percent difference is then determined. The percent difference between the measured and theoretical forces was almost nearly zero for all increments. We did have some discrepancy between the measured and theoretical depths to the center of pressure. The percent error of depth to the center of pressure ranged from 1.79% to 50.42%. Following is the graphs for the hydrostatic pressure and the distance to the centre of pressure for both partially and fully submerged.

Figure 3 hydrostatic pressure and the distance to the centre of pressure for both partially and fully submerged.

Figure 4 hydrostatic pressure and the distance to the centre of pressure for both partially and fully submerged.

Question 3The force applied in the system vertical face of buoyant material counter acts the mass added to the hanging arm. so we know that if we move away from the sea level, the pressure will change either with air or water. So in our experiment also change in pressure because of the weight of the water above and buoyant forces clearly show the properties of water. The water pressure was so high that we add the mass 50 g to 450g even still quadrant was able to support it in static equilibrium. So the idea let us to believe that the curved area allows for a larger surface with which the water can act upon for less change in depth. This would explain such a large jump in force applied after breaking the upper plane of the vertical face.

ConclusionThe graphical analysis of our lab shows that a linear relationship between Hydrostatic force and Average Depth for the Partially Submerged and the graph of Hydrostatic Force and Average Depth for Fully Submerged is also linear. Our Theoretical force compared to the measured force were nearly identical with a percent errors of 2.04e^-14%. The error in the distance to the centre of pressure compared to the theoretical was outrageously high with a percent error of 50.42%. The graphical analysis showed a linear relationship between Hydrostatic Force and Average Depth for only fully submerged. The graph of Hydrostatic Force and Average Depth for partially submerged is not perfectly linear.

ReferenceFuller, J. (2017) Fluid Mechanics Lab. Hydrostatic Pressure. Retrieved from johnefuller.weebly.com/uploads/1/7/8/7/17878951/hydrostatic_pressure_lab.pdf. Assessed on 31/8/2017.

ME-495 Laboratory Exercise – Number 7 – Hydrostatic Pressure – ME Department, SDSU – Kassegne http://www.digitaladdis.com/sk/ME495_HydrostaticForce.pdf