report on Civil engineering project

REPORT WRITING AND DISCUSSION 1. Use the spreadsheet with your own experimental results and the two spreadsheets sum- marising all groups results for preparing your report. Study the summary spreadsheet and nd out how it was created. If you feel condent, you can develop a similar spreadsheet of you own. 2. Include the graph of Cp versus  to your report. Compare this graph with the standard results on Figure 3. Comment on the shape of the graph and on dierences between you results and standard results. 3. Using the data from the summary spreadsheets calculate the drag coecient using equation (5) and the drag per 1m span of the cylinder by equation (3) for two cylinder diameters. A method of numerical integration using spreadsheets is discussed in Appendix 2. You can use the template provided in the \Integration template" worksheet. 4. Plot (i) drag D as a function of free-stream velocity U1 for two cylinder diameters on one plot and (ii) drag coecient CD as a function of Reynolds number for two cylinder diameters on another plot. Compare the graphs and discuss which of them is more useful for practical applications. 5. Compare the observed values of the drag coecient with the standard results presented on Figure 2. Comment on dierences between the measured and standard results. Is the drag due to shear stresses important for the studied range of Reynolds numbers? Discuss the variations of measured drag coecients with Reynolds number. 6. Include the graph of the wake velocity prole in your report. Comment on the shape of the graph. Why is the velocity in the wake lower then the free-stream velocity? Why is the uniform velocity outside the wake higher than the free-stream velocity? 7. Give a general discussion of your results. Discuss the physics of drag generation. Why is the representation of drag in the non-dimensional form of drag coecient important? What is the role of experiments in obtaining universal relations of drag coecients to Reynolds number? What is the practical importance of such relations? 8. Apply the results of your experiment to the following practical problem: A radio mast has a 5m long cylindrical section 0.2m in diameter. Find the wind speed when the results of your experiment can be used for calculating wind load on the mast. Calculate the total load on the section at this speed assuming a uniform wind prole. 9. Make general conclusions to your report. 9