A one-third scale model of an airplane is to be tested in water. The airplane has a velocity of 900 km Ii in air at -50°C. The water temperature iii the test section is 10°C.
The properties of air at 1 atm and -50°C:
The plopelties of water at 1 atm and 10°C:
In order to achieve similarity between the model and the prototype, the water velocity on the model should be
(a) 97 km/h
(b) 186 km/h
(c) 263 km/h
(d) 379 km/h
(e) 450 km/h
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Fluid Mechanics: Fundamentals and Applications
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