【摘要】 为研究射流引起的纵向涡对流动和换热性能的影响,采用数值方法模拟了三维矩形通道内有射流从底面进入时的定常、不可压层流对流换热,得到了纵向涡影响下的速度场和温度场以及沿流动方向局部Nusselt数的分布。以场协同原理为指导,分析了射流纵向涡强化换热的原因,并进一步研究了射流角对纵向涡的换热强化效果的影响。结果表明:纵向涡改善了通道内速度场和温度场的协同关系,强化了对流换热;射流垂直底面入射时,纵向涡的换热强化效果较好。更多还原

【Abstract】 The heat transfer enhancement due to longitudinal vortices induced by jets was analyzed numerically for steady-state, incompressible laminar flow in a three-dimensional rectangular channel with jets entering through the bottom wall. The velocity and temperature fields were obtained along with the local Nusselt numbers along the flow direction as a function of jet angle. The field coordination principle was used to explain the heat transfer enhancement by the jet-induced longitudinal vortices analyzed. The results show that the longitudinal vortices improve the coordination between the velocity and temperature fields in the channel which enhances the convective heat transfer. Better enhancement is achieved when the jets are normal to the flow.更多还原