Question

2. (15pts) You have been asked by a baseball manufacturer to study how certain stitching patterns on a baseball prototype affect travel distance. Using principles of dynamic similarity you make a baseball model that is three times the size of a regular baseball and you place it in a wind tunnel. You remember from fluid mechanics that the Reynolds (Re) number is important to this problem (see class notes for Re number derivation) (a) What parameters must be controlled to model the baseball performance? (b) What should be the speed of the wind tunnel to simulate a baseball speed of 25.0 ms1in air? (c) To visualize the flow, you decide to make measurements in water rather than air and therefore use a water flow tunnel. What should the flow speed be in this water tunnel? Assume the air temperature is 15°C and the experiment is at sea level. The water temperature is 20°C

Answer 1

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