A model was tested of a tractor-trailer rig is performed in a wind tunnel. The drag force, FD, is found to depend on frontal area, A, wind speed, V, air density, r, and air viscosity, µ. The model scale is 1:4; frontal area of the model is 0.625 m^2. Obtain a set of dimensionless parameters suitable to characterize the model test results. State the conditions required to obtain dynamic similarity between model and prototype flows. When tested at wind speed V = 89.6 m/s, in standard air, the measured drag force on the model was FD = 2.46 kN. Estimate the aerodynamic drag force on the full-scale vehicle at V = 22 m/s. Calculate the power needed to overcome this drag force if there is no wind.

A model was tested of a tractor-trailer rig is performed in a wind tunnel. The drag force, FD, is found to depend on frontal area, A, wind speed, V, air density, r, and air viscosity, µ. The model scale is 1:4; frontal area of the model is 0.625 m^2. Obtain a set of dimensionless parameters suitable to characterize the model test results. State the conditions required to obtain dynamic similarity between model and prototype flows. When tested at wind speed V = 89.6 m/s, in standard air, the measured drag force on the model was FD = 2.46 kN. Estimate the aerodynamic drag force on the full-scale vehicle at V = 22 m/s. Calculate the power needed to overcome this drag force if there is no wind.

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 5.13P: 5.13 The torque due to the frictional resistance of the oil film between a rotating shaft and its...

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