Wind tunnel test is often conducted to check aerodynamic stability of long-span bridges. To properly conduct wind tunnel test, aerodynamic similarity conditions should be made equal between the proposed bridge and the model. Reynolds Number is one of these conditions and is defined as ratio of inertial force to viscous force of wind fluid. With equality of Froude Number, it is difficult to achieve equality in Reynolds Number.
For instance, for a model scale of 1/40 to 1/150, the ratio of Reynolds Number between the bridge and the model varies from 252 to 1837 with a difference of order from 100 to 1000. As such, similarity of Reynolds Number between real bridge and model is often neglected.
This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.
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