FXD型动力集中动车组暖风机通风域流动特性评价及分析

Evaluation and Research on the Flow Characteristics ofthe Ventilation Area of the Heater in a Power Centralized CRH

运用数值模拟的方法,针对FXD型动力集中动车组暖风机进出风口通风域回流严重致设备频繁停机的问题,引入特征参数热风出流率K作为评价指标,采用Realizable k-ε湍流模型来模拟系统内空气的湍流运动,重点分析了流动参数和结构参数对冷、热空气流动特性的影响。计算结果表明增大风量能提高K值,但提升幅度很小,且对减弱回流没有贡献;调整进、出风口导流板角度至65°~70°区间内能够一定程度减弱回流现象,提高K值;而采用增加隔板的优化导流结构方式则有效的遏制了通风域回流现象,显著提高K值,建议隔板宽度取导流空间宽度的70%~80%。

In this paper,the numerical simulation method is used to solve the problem of frequent shutdown of the equipment caused by serious backflow in the ventilation area of the air heater inlet and outlet of a certain power centralized CHR.The characteristic parameter K is introduced as the evaluation index and realizable k-εturbulence model is used to simulate the air turbulence in the system.The effects of flow parameters and structure parameters on the flow characteristics of cold and hot air are analyzed.The calculation results show that increasing the air flow rate can increase K value,but the increase range is very small,and it has no contribution to weakening the return flow.Adjusting the angle of the air inlet and outlet guide plate to 65°~70°can weaken the return flow phenomenon to a certain extent,and increase K value.While the optimization of the diversion structure by adding the baffle plate can effectively curb the return flow phenomenon in the ventilation area,and significantly improve K value.It is suggested that the baffle plate width should be taken as the guide 70%~80%of the flow space width.