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Intuitive Derivation of Reynolds Number

Randall D. Peters·Loren Sumner
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Abstract

It is evident from the literature that many engineers describe the Reynolds number qualitatively as ``the ratio of inertial forces to viscous forces''. Yet it is not immediately obvious that the well known expression Re = LV(rho)/(eta), which involves the size L of a solid object moving with speed V relative to a fluid of density rho and viscosity eta--is in fact a ratio of forces. It is hoped that the following treatment, which is based on an energy rather than force perspective, will help to de-mystify the important parameter given to us by Osborne Reynolds

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Randall D. Peters, Loren Sumner. 2003-06-27. Intuitive Derivation of Reynolds Number. https://arxiv.org/abs/physics/0306193

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