i want to differentiate value boundary layer parameter such as boundary layer thickness and momentum thickness for below two cases for water fluid.
Case(1) boundary layer parameter such as boundary layer thickness and momentum thickness by considering without viscous heating(i.e viscosity is constant and no wall heating)
Case (2) boundary layer parameter such as boundary layer thickness and momentum thickness by considering with viscous heating(i.e viscosity is vary with temperature and wall heating also)
Hi,
As viscosity generally decreases with an increase in tempertaure, local Reynolds number will increase and viscous boundary layer thickness will decrease delta~1/sqrt(Re). The prandtl number will aslo decrease and as delta/delta_thermal~Pr^1/3, the thermal boundary layer may relatively increase.
However, viscous heating in liquids requires quite extreme conditions - Large Eckert number>1 - you would need very high velocity, viscosity or microscales.
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