THE PHYSICAL ASPECT OF THREE-DIMENSIONAL MIXED CONVECTION IN A UNIFORMLY HEATED HORIZONTAL PIPE
الكلمات المفتاحية:
horizontal pipe / uniform heating / laminar mixed convection / numerical simulationالملخص
This study concerns the numerical simulation of the three dimensional forced and mixed convection
heat transfer in a uniformly horizontal heated pipe. The complete Navier-Stokes equations are
numerically solved with a finite volume method.. The obtained results show that the mixed convection
flow is quite three-dimensional. As the Grashof number is increased, a secondary flow develops in the
form of a two counter-rotating vortices. The vortices lead to a better mixing of the flow and thus enhance
the convective heat transfer: the local axial Nu decreases along an entrance region and then increases
downstream instead of leveling off as in the case of forced convection. The increase is more important for
higher Richardson numbers
التنزيلات
المراجع
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