| Summary: | The mixed laminar boundary layer flow and heat transfer on a permeable stretched surface moving with prescribed skin friction are studied. Three major cases, which correspond to complete similarity solutions, are considered. The cases are combinations of power law indices n and m representing temperature and skin friction distributions, respectively. The first case ( n = 0, m = 0.5) corresponds to isothermal stretched surface with skin friction at the surface scales as x 1/4 . The second case ( n = 1, m = 1) is a linear temperature and skin friction distribution along the vertical stretched surface. The third case ( n = −1, m = 0) represents inverse temperature variation along the surface with prescribed skin friction of the order of x −1/2 . Similarity solutions are obtained for the surface stretched in a stagnant air with Prandtl number = 0.72. The effect of suction/injection velocity ( f w ) and the buoyancy parameter ( λ ) is studied in detail. The results show that the heat transfer coefficient along the surface is enhanced for assisting flow ( λ > 0) at any value of f w for the first and second cases, while it is reduced for the third case. However, the opposite is true for the opposing flow ( λ < 0). Furthermore, suction enhances the heat transfer coefficient, whereas injection degrades it at any fixed λ for the first and second prescribed skin friction boundary conditions, and the opposite is true for the third case.
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