The drag characteristics of an airplane will be determined from model tests in a wind tunnel operated at an absolute pre
Posted: Fri Jul 08, 2022 6:32 am
The drag characteristics of an airplane will be determined frommodel tests in a wind tunnel operated at an absolute pressure of1300 kPa. If the prototype is to fly at an altitude where thepressure is 54 kPa and at a speed of 385 km/h, then the speed ofthe model must not differ by more than 20% from the speed of theprototype. What range of length scales can be used if Reynoldsnumber similarity is to be maintained? Assume that compressibilityeffects can be ignored, that viscosity is not affected by pressure,and that the temperature of the air in the tunnel is equal to thetemperature of the air in which the prototype will fly