A student needs to measure the drag on a prototype of characteristicdimension d p moving at velocity U p in air at standardatmospheric conditions. He constructs a model ofcharacteristic dimension d m , such that the ratio d p / d m issome factor f . He then measures the drag on the model atdynamically similar conditions (also with air at standardatmospheric conditions). The student claims that the dragforce on the prototype will be identical to that measured onthe model. Is this claim correct? Explain.

A student needs to measure the drag on a prototype of characteristicdimension d p moving at velocity U p in air at standardatmospheric conditions. He constructs a model ofcharacteristic dimension d m , such that the ratio d p / d m issome factor f . He then measures the drag on the model atdynamically similar conditions (also with air at standardatmospheric conditions). The student claims that the dragforce on the prototype will be identical to that measured onthe model. Is this claim correct? Explain.

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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Similar questions

A 1:20 scaled-down model of a hydrofoil is tested in a water channel, at a velocity of 0.179 m/s. At this velocity, a drag force of 2.2 N is measured. Determine the drag force of the original hydrofoil, at a velocity of 0.8 m/s.
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2) A prototype ship is 50 m long and designed for cruising speed of 10 m/s. The drag is to be simulatedby a 1-m-long model that will be towed in a towing tank. Using Froude scaling, determine the tow speedand the ratio of the model to prototype drag and power.
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