Transport in ThermofluidsME220BHomework #3Problem 1:Consider Poiseuille flow between parallel plates separated by a distance W. Try to evaluate the appropriateness of critical Reynolds number Re2300D≈(rule of thumb) based on our understanding of the transition between the laminar viscous sublayer and turbulent inner region described by the law of the wall. To this end, find an expression for the wall coordinate at mid-distance between the plates (/ 2)yW+in terms of the coefficient of friction fcand the Reynolds number ReD(based on hydraulic diameter). Assume that the flow between the plates is mostly enveloped by the viscous sublayer and determine fcas a function of ReDfor a laminarflow. Combine this result with the critical Reynolds to evaluate (/ 2)+. Does (/ 2)+fall within the transition region between the viscous sublayer and the inner region of the wall turbulence? Comment on the significance of this result.
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