A 1:20 scale model of a submarine is tested in a wind tunnel to measure the drag on the proposed design. A prototype speed of 18kmph is desired. What speed should be used in the wind tunnel for the model testing? Estimate the ratio of drag forces between the model and the prototype. Use the following property values:
|
Fluid
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Density
kg/m3
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Viscosity
N-s/m2
|
|
Air
|
1.22
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1´10-5
|
|
Sea water
|
1025
|
1.5´10-3
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