This page contains links to the PDF versions of the lab exercises. The class material is provided as a convenience to students enrolled in the class. Anyone visiting this site is welcome to download and use these notes and lab exercises for their own education.
This material is copyright © 2001-2006 Gerald Recktenwald. All rights reserved. These notes may not be reproduced and distributed for profit using any means, or in any form without permission in writing from the author, Gerald Recktenwald.
Use of these materials in courses at other academic institutions can be arranged. Please to let me know that you are using my notes. I would like proper attribution for these materials.
The description of the short report format provides overall guidance for preparation of lab reports. The grading rubric for each report is provided with each lab assignment.
Calibration equations for the pressure tranducers are described in a separate document. MATLAB codes for converting the pressure transduer output can be downloaded here.
The assignment for measuring the heat transfer coefficient from a single low profile package was handed out in class.
There was a small bug that might cause aveAgilentDataGUI
to hang. An updated version of
aveAgilentDataGUI is now available on the web
page for MATLAB codes for the class. As usual, I recommend
downloading the
entire zip archive
of codes to get the latest version of all the files.
The archive does not contain the three files linked
below for data reduction
Also note that sometimes Benchlink will write a text file with
an incomplete last line. If that happens you will get an error
message from aveAgilentDataGUI that looks like this:
Error in loadColData:
number of data points = 26617 does not equal nrow*ncol
data: nrow = 831.781250 ncol = 32
The solution is to open the data file (the file exported by Benchlink) and delete the incomplete last line from the bottom.
Use the following MATLAB code and sample data file as a start on the data reduction. The mfiles are not finished! You will have to add code.
getBlockData.mgetBlockData.m
reads the MAT file exported by aveAgilentDataGUI
and converts thermocouple voltages and thermistor resistance to
temperature. The uncertainties in the sensor data are also
computed and returned to the calling program. To complete this
function you will need to (1) add lines in the code to convert
other voltages to temperatures, including computing averages
of temperatures; and (2) add more variable names to the return
argument list. Think first, then write code.
Make a list on paper of the variables you will need for
data reduction. Any of these variables that are temperatures
(along with their uncertainties) should be computed in
getBlockData and returned in the output argument
list of getBlockData.
reduceBlock.mreduceBlock.m
calls getBlockData
and peforms data reduction to compute the heat transfer coefficient.
Again, think first, then write code. The
data reduction formulas you developed for the homework
assignment should appear in the reduceBlock
function. Better yet, I recommend that you write
another function, say htc.m that has the single task
of computing the heat transfer coefficients given all
of the input temperatures and geometric variables. That
function would have a similar role to nozzleFlow.m
for the flow bench data reduction. The advantage of a separate
htc function is that it makes the sequential perturbation
calculation easy and clean to implement.
sampleBlockData.matsampleBlockData.mat
is a MAT file will averaged data from two measurements of heat transfer
coefficient. You can use sampleBlockData.mat
to learn how getBlockData and reduceBlock
work. You will use your own data file with your modified
versions of getBlockData and reduceBlock.
The grading rubric will be posted later. This lab will not have a formal lab report.
The assignment for measuring the loss coefficient of perforated plates was handed out in class.
Since I posted this assignment late, it is OK for you to turn in your report by noon on Friday, 19 May. I'm sorry for taking so long to provide this rubric. A series of deadlines over the past week and a half has interfered with my ability to provide timely feedback for the class. I will be digging out from my backlog this week. I'm sorry that my schedule has caused problems.
The following table provides the grading rubric that is used to score your report. Be sure to address each of the categories in your report. The Max Score column allows you to see the relative importance of each category.
| Category | Max score |
| Accuracy and format of sketches | 5 |
| Report of raw data | 10 |
| Equations for uncertainty analysis | 15 |
| Tabular and graphical display of results | 40 |
| Computation of loss coefficient and comparison with Idelchik | 15 |
| Discussion | 15 |
| Grammar, spelling, organization and clarity of prose | 10 |
| Total | 110 |
There are a lot of similarities between this lab (number 4) and the preceding lab on fan curve measurements. There is no need to reproduce all of the information that you included in the preceding lab. For example, you do not need to describe how the flow bench works, or the equations for calculating the flow rate. On the other hand, if you have already completed a lot of writing (or cloned it from the preceding lab), there is no need to remove that material either.
List the parameters that controlled the raw data collection with Benchlink: scan interval (frequency), channels scanned, resolution (number of digits), and input range.
Include the raw averaged data in an appendix. Do not
include a print out of all of the data saved by the Benchlink
data logging software. We are only interested in the averaged
data created with flowBenchDataSelector.
One way to get the values of the averaged data is to print it out in
the MATLAB command window with the
dumpFlowBenchStats function.
Briefly describe the uncertainty calculations in
lossCoeffStats and its subordinate mfiles. How is
the uncertainty in the flow rate computed? Briefly list the sources
of uncertainty for each of the input variables in the formula
for flow rate.
Briefly discuss how the data reduction process differs from the previous lab. A short paragraph is sufficient. In the appendix of the report, include print outs of spreadsheets or MATLAB program listings. Include only those MATLAB listings of programs you modified.
Present the pressure drop versus flow rate data in tables and plots. Include one table for each perforated plate. Identify the hole diameter, hole spacing and free area ratio for each plate.
For the data you recorded, give the value of the loss coefficient in the form Dp = c*Q2 and h = KLV2/(2g).
Discuss the agreement between your measured data and the loss coefficient from Idelchik's formula.
All tables and figures must be numbered and have a caption. Refer to the description of the short report format for examples.
The assignment for fan curve measurement was handed out in class.
The due date for the lab report is changed to noon on Friday, May 5, 2006. That should give you time to incorporate any information from the grading rubric, which was posted on Wednesday, May 3, 2006.
The following table provides the grading rubric that is used to score your report. Be sure to address each of the categories in your report. The Max Score column allows you to see the relative importance of each category.
| Category | Max score |
| Accuracy and format of sketches | 10 |
| Report of raw data | 5 |
| Equations for data reduction | 15 |
| Tabular and graphical display of results | 40 |
| Discussion | 15 |
| Grammar, spelling, organization and clarity of prose | 10 |
| Total | 95 |
Include at least one sketch of the flow bench and one of the sensor wiring. Images from this web page will probably save you time and effort. List the sensors and digital multimeter (manufacturer, model number) used to make the measurements. A table would be a good way to present this list.
Include the raw data in an appendix. A print out of the spreadsheet form of the data would be nice.
Briefly list the equations used to perform data reduction. You do not need to list all of the polynomial coefficients for thermocouple conversion. The critical equation is the conversion of pressure and temperature data to flow rate. Define all variables the first time they are used. Consult the description of the short report format for guidance.
Describe how you converted the raw flow bench sensor readings to flow rate and fan pressure rise. In other words, identify and briefly describe your process of performing the calculations (either by manual calculations, spreadsheet, or MATLAB programs). A short paragraph is sufficient. In the appendix of the report, include print outs of spreadsheets or MATLAB program listings. Include only those MATLAB listings of programs you modified. If you performed all calculations by hand, provide a sample calculation in the appendix.
Describe where/how you obtained the manufacturers data. Include numerical values from the manufacturer's fan curve in a table.
Provide coefficients of the curve fits in tables.
Present the reduced flow rate and pressure rise data in tables and plots. Include one table for each fan voltage. Combine fan curves for both voltages and the manufacturer's data on the same plot. your converted temperature data in a table. Numerical quantities (temperature, EMF, flow rate, pressure rise) must have units. Identifying the units in the column headings is preferred.
All tables and figures must be numbered and have a caption. Refer to the description of the short report format for examples.
Discuss the trend in fan performance as a function of supply voltage. Also comment on the agreement between your measured data and the manufacturers data. Now that you have experience using the flow bench, would you do anything differently, i.e. should anything in the lab procedure be changed?
The assignment for velocity profile measurement.
The following table provides the grading rubric that is used to score your report. Be sure to address each of the categories in your report. The Max Score column allows you to see the relative importance of each category.
| Category | Max score |
|---|---|
| Anemometer Comparison | 10 |
| Velocity Profiles | 25 |
| Discussion | 15 |
| Grammar, spelling, organization and clarity of prose | 10 |
| Total | 60 |
Are the differences significant? What are plausible causes for the differences?
Is there enough data to provide reasonable resolution of the boundary layer? Are the data plausible? Do profile plots use the format described in the assignment.
Are the velocity profiles for the two inlets similar? Are they significantly different? Which inlet style is recommended?
The assignment for thermocouple construction and comparison was handed out in class. The link in the preceding sentence is to a revised version of that document.
The following table provides the grading rubric that is used to score your report. Be sure to address each of the categories in your report. The Max Score column allows you to see the relative importance of each category.
| Category | Max score |
| Accuracy and format of sketches | 10 |
| Report of raw data | 5 |
| Conversion of ice-bath and zone-box compensated thermocouple circuits | 30 |
| Discussion | 15 |
| Grammar, spelling, organization and clarity of prose | 10 |
| Total | 70 |
Include at least two sketches: one showing the layout of the lab equipment; another showing the wiring circuit for the two ice-point compensated thermocouples. The sketches do not need to be elaborate. In particular, the sketch of the equipment should be a schematic, not an artist rendering of the equipment. An annotated digital photograph would be acceptable.
Report the raw data as voltage (EMF), resistance, and direct readings from the bulb thermometer and the panel meter.
Conversion of the thermocouple outputs will be graded primarily on correctness of your reported values. Provide a short description of the compuational process for converting the voltages to temperature. Show one example (either hand calculation, MATLAB session, or spreasheet excerpt) of the calculation details. Do not list MATLAB programs unless you wrote them.
Present your converted temperature data in a table. Numerical quantities (temperature, EMF) must have units. Identifying the units in the column headings is preferred.
All tables and figures must be numbered and have a caption. Refer to the description of the short report format for examples.
The discussion should include comparision of the outputs of the different temperature sensors and the different thermocouple circuits. Which sensor or circuit is most accurate? What accounts for the differences between the sensors and circuits?