Effects of longitudinal curvature, vorticity and displacement for two-dimensional turbulent boundary layers with heat and mass transfer (original) (raw)
A general theory for two-dimensional turbulent boundary-layers on curved surfaces with heat and mass transfer is formulated, when on coming stream contains the vorticity and gradient of enthalpy. The present work employees the method of matched asymptotic expansions and deals with underdetermined equations of mean motion. The analysis shows that in presence of mass transfer even the lowest-order solution of turbulent boundary-layer is global in nature due to an induced pressure gradient and tangential velocity by displacement of basic indiviscid solution by outer layer. Further, it shown that wall (inner) layer is affected by mass transfer, while defect (outer) layer by mass transfer, displacement, curvature, vorticity and enthalpy gradient. In the overlap regions of inner and outer layers, the matching leads to logarithmic laws, whose constants depends upon the parameters of respective problems. Linearity of the equations is exploited to separate various elIects.
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