CFD预测不同进风方向对蒸发式冷凝器流场的影响

CFD simulation of airflow distribution with different inlets in evaporative condenser

为能够准确真实地研究蒸发式冷凝器工作状态下内部温度场和气流场的变化情况,建立蒸发式冷凝器三维模型,利用CFD模拟软件Fluent对蒸发式冷凝器工作状态时内部流场进行非稳态模拟,并分析5s内3种进风方向(壳体单面进风、壳体双面进风、壳体双面顶部一面进风)对冷凝器内部温度场以及气流场的影响。结果表明:单面进风时,冷气流水平侵入冷凝器底部,在密度差作用下上升并与冷凝盘管进行换热;双面进风与单面进风相比,能够减少管壁和壁面处漩涡的数量与强度;三面进风时,冷凝器内腔温度经历一个短暂下降再上升的过程。在今后的设计中,还可以通过改变进风面积以及进风角度等参数来优化蒸发式冷凝器的换热效率。

The variation of the internal temperature field and airflow field in the evaporative condenser was discussed when it was worked under an unsteady state numerical simulation by using CFD software.The performance of internal temperature field and airflow field was analyzed when the condenser worked within 5swith different air inlet direction（single inlet,double inlets,and three inlets）.The simulation results showed that when the condenser worked with single inlet,the cold airflow was easily infiltrated the bottom of the condenser horizontally,then rose and got heat exchange with coils under the effect of density difference.The condenser which has double inlets could decrease swirls＇ number and intensity that caused by the disturbance of coils and walls.Furthermore,when the condenser worked with three inlets,the cavity temperature of condenser would experience a process of fall first and then rise.In the future study,the airflow inlet area and air inlet angle can also be changed to optimize the heat transfer efficiency of the evaporative condenser.