Heat Transfer: NonDimensional Parameters

As is common with fluid mechanics analysis, a number of dimensionless parameters are employed to describe convective heat transfer. A summary of these variables is included in the following tables: 
General Convection (Forced and Free) 
Parameter  Formula  Interpretation 
Prandtl Number:  Ratio of fluid velocity boundary layer thickness to the fluid temperature boundary layer thickness.  
Nusselt Number:  Ratio of heat transfered from surface to heat conducted away by fluid. 
Forced Convection Only 
Parameter  Formula  Interpretation 
Reynolds Number:  Ratio of fluid inertia stress to viscous stress (for flow over flat plates).  
Reynolds Number:  (Reynolds Number for pipe flow).  
Stanton Number: 
Free Convection Only 
Parameter  Formula  Interpretation 
Grashof Number:  Ratio of fluid buoyancy stress to viscous stress.  
Rayleigh Number: 
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