A one-fourth scale model of a car is to be tested in a wind tunnel. The conditions of the actual car are V = 45 km/h and T = 0°C and the air temperature in the wind tunnel is 20°C. In order to achieve similarity between the model and the prototype, the wind tunnel is run at 180 km/h. The properties of air at 1 atm and 0°C: ? = 1.292 kg/m3, ? = 1.338 × 10−5 m2/s. The properties of air at 1 atm and 20°C: ? = 1.204 kg/m3, ? = 1.516 × 10−5 m2/s. If the average drag force on the model is measured to be 70 N, the drag force on the prototype is (a) 66.5 N (b) 70 N (c) 75.1 N (d ) 80.6 N (e) 90 N

A one-fourth scale model of a car is to be tested in a wind tunnel. The conditions of the actual car are V = 45 km/h and T = 0°C and the air temperature in the wind tunnel is 20°C. In order to achieve similarity between the model and the prototype, the wind tunnel is run at 180 km/h. The properties of air at 1 atm and 0°C: ? = 1.292 kg/m3, ? = 1.338 × 10−5 m2/s. The properties of air at 1 atm and 20°C: ? = 1.204 kg/m3, ? = 1.516 × 10−5 m2/s. If the average drag force on the model is measured to be 70 N, the drag force on the prototype is (a) 66.5 N (b) 70 N (c) 75.1 N (d ) 80.6 N (e) 90 N

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.70P

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