Similarity with Heat Transfer Simple Applications

Fortunately, most cryogens, with the exception of helium II, behave as classical fluids. As a result, it has been possible to predict their behavior by using well-established principles of mechanics and thermodynamics applicable to many room-temperature fluids. In addition, this has permitted the formulation of convective heat transfer correlations for low-temperature designs of simple heat exchangers that are similar to those used at ambient conditions and utilize such well-known dimensionless quantities as the Nusselt, Reynolds, Prandtl, and Grashof numbers. 

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