Abstract:The reynolds stress model and the Cross viscosity equation have been adopted to simulate the turbulent flow and temperature fields of the dilute polyacrylamide(PAM) solution in a two-dimensional axisymmetric circular tube.The effect of flow velocity on drag reduction and heat transfer performance of drag-reducing fluid have been investigated systematically.The results indicate that the drag reduction(DR) and heat transfer reduction(HTR) of drag-reducing fluid increase with increasing flow velocity and approach the asymptotes,and HTR is greater than DR all the time.The comparison between Colburn factor and friction coefficient shows that Colburn analogy is not so much applicable to the drag-reducing fluid,especially for the low bulk flow Reynolds number conditions.
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