CIVL 321 LABORATORY Spring 2024 Laboratory Group Report Format Organization of Report: I. Title page (see sample) II. Laboratory description handout III. Results table IV. Graphs* V. Answers to questions* VI. Appendix a. Raw data sheet b. Complete set of sample calculations * as requested in handout General Instructions: 1) Report must be complete, neat, and legible. 2) All pages must be 81/2" x 11", and bound/stapled together in the correct order. The name of the person who prepared each page (except the Title page) must appear in the lower right corner. 3) All report content must be typed, with the exceptions of: 1) The sample calculations. These can be handwritten. 2) The raw data information may also be handwritten on the data sheet. 4) Results tables must be prepared in a spreadsheet program or equivalent with appropriate headings. The dimensional units for all displayed results must be clearly indicated. 5) The sample calculations must take one set of data and show each calculation required to generate the Results table, produce the graphs, and answer the questions (if applicable). All unit conversions must be shown and all calculations must carry at least three (3) significant digits. Sample calculations may be handwritten in pen or pencil – but they must be extremely neat. 6) Graphs must be prepared in a graphing program such as Excel or Matlab and follow accepted engineering practice as indicated below and shown in the example on the following page: a. b. C. d. e. f. g. Each graph must contain a meaningful title that describes its content. Coordinate axes must be appropriately scaled and have major gridlines. Coordinate axes must be labeled with words, symbols (if applicable), and proper units. Experimental data should appear as marker symbols without lines. If requested, x- and y- error bars should be indicated on each data point. Theoretical curves should appear as smooth lines without marker symbols. They should be clearly labeled to indicate they are theoretical results. Least-square curve fits (Trendlines) must be accompanied by the curve fit equation and R² value with at least three (3) significant digits shown. Multiple data sets on the same graph should be clearly identified through the use of labeling or a legend. Grading: The laboratory experiments reports are expected to be neat, succinct, and well written. Unless otherwise stated, all reports must be submitted at the beginning of the laboratory period following the performance of the experiment. Late reports will not be accepted. All students who contribute to the experiment and report will receive the same grade. Sample Title page Specify lab by group number, day, and time. Names listed in alphabetical order by last name Drag Coefficient Measurement of an Ogive-shaped Projectile in Subsonic Flow Drawdown (m) Sample Graphs & Tables Graphs have meaningful title, axis labels with proper units. Note that the titles tell me more than just "Drawdown vs. time", which I should know already just by looking at the axis labels. Clear legend, data as markers, theoretical as line, and at least 3 significant digits in regression equations. Tables have clear headings for each column with the dimensional units clearly specified. Values are listed with appropriate number of significant digits. 2 Line fit to drawdown at 80 m from well using log transformed time (first 4 data points removed) 1.8 1.6 drawdown (m) 1.4 1.2 1 0.8 0.6 drawdown (obs) Linear (drawdown (obs)) y=0.5912x+ 0.0865 R² = 0.9988 0.4 0.2 0 0 1 2 3 log time (min) Drawdown at 80 m from pumping well Time (min) Drawdown (meters) 2 1.8 0.5 0.16 1.6 1 0.18 2 1.4 0.24 3 0.27 1.2 4 0.47 1 Drawdown (obs) 5 0.50 0.8 Theis solution 7 0.57 0.6 10 0.68 20 0.84 0.4 30 0.96 0.2 50 1.06 0 100 1.29 0 200 400 600 800 1000 1200 Time (min) 200 1.46 500 1.68 1000 1.86/n CIVL 321 LABORATORY Spring 2023 Objective: Fluid Mechanics Lab #5 Water Flow over a Triangular (V-notch) Weir The student is to measure the volume flow rate over a triangular weir and experimentally obtain the value of the unknown coefficient Cwr for the equation 10.34 on p. 584 (equation 1 below) given in the textbook Fundamentals of Fluid Mechanics, 8th Edition, by Gerhart, et. al. The equation can be derived using Bernoulli's Equation. The experiment is designed to introduce the student to one of the methods used in measuring the flow rate of water for irrigation and for supplying large municipalities through large open channels. 8 15 Q = C tan(+)√2gH Procedure: (1) 1. Become familiar with the operation of the hook-gage and the operation of the balance on the weigh tank. 2. The zero-level reading of the hook-gage will be taken with the water level at the bottom of the V-notch of the triangular weir. This will be the datum for the remaining height measurements. 3. The volume flow rate (discharge) over the triangular weir will be determined using a stop watch to measure the time needed to catch a certain weight of water. The operating procedure of the weigh tank will be demonstrated by the instructor. Two weight-time measurements should be made for each water level height, H, above the V-notch measurement. If the times differ by more than 1 percent, another measurement should be made. Depending on the flow rate being measured, a different weight will be used. Use enough weight to get at least 1 minute's worth of data. For the lowest flows, 100 lb will suffice; for the highest flows 1500 lb or more is required. 4. The volume flow rate at 6 heights will be measured. Use the marks indicated on the weir plate as an approximate guide. Accurate height measurements are made using the hook-gage. Note that the hook- gage readings are in 10th's and graduation marks are in 100th's of a foot. 5. Measure the water temperature at each water level used during the experiment. 6. Estimate the measurement uncertainties for the weight, time, water density, and the hook-gage reading, H. Material to be Included in Report in Addition to Normal Requirements: 1. Determine the volume flow rate (discharge) in ft³/s (cfs) for each water-level height, H, over the triangular weir using the weigh tank formula Q = W/pgat. 2. Plot the volume flow rate Q in cfs versus the water level height, H, in ft using Excel. 3. Determine the total uncertainty in the flow rate measurement (σQ) from the individual uncertainties in weight, time, and water density. Using the uncertainties in Q, add error bars in the y-direction to the data markers on the graph. 4. Use the Regression Tool under Data Analysis to obtain an equation for the data of the form Q = K H³². Alternatively, graph your data in this form (Q vs. H5/2) and plot your best-fit line through the data. Be sure to set the intercept to zero and display the equation and R²-value on the graph with at least three significant digits for all values. == 5. From the regression value of K and the geometry (0 = 61° ±1°) of the sharp-crested triangular weir, determine the weir coefficient Cw, as defined in equation 1. This value is valid for the range of heads used in the experiment. Compare this value to what is given in Figure 10.21 on p. 590 and comment on your results. 1 Scanned with CamScanner DATE: GROUP: DATA SHEET FOR TRIANGULAR WEIR Weir Angle, 6, radians ± radians Hook Gage Zero Reading, Ho = 4.63 ft± ft Flow rate and height measurements H₂O Weight Level No (lb) 1 H₂O Height Temp Atı At₂ At if needed (ft) (s) (s) (s) Ataverage (s) 2 3 4 5 6 Scanned with CamScanner