汽车前舱热气流对制动盘散热性能的影响

Effect of hot airflow of automobile underhood on dissipation performance of brake disk

针对制动盘对流传热计算多基于单个制动盘或基于整车外壳模型下的制动盘,未考虑汽车前舱内高温气流对制动盘散热性能影响的问题,基于含有前舱部件的某SUV整车模型,对其通风制动盘散热性能进行数值计算并分析,得到在不同前舱产热工况以及不同车速下通风制动盘的外流场、外温度场、表面对流传热系数和散热功率.在前舱热源相同时,车速变高会提高制动盘对流传热性能,而在车速固定时前舱热源越大则制动盘的散热性能越差.

As to the issue that the calculation of convective heat transfer of brake disk is mostly based on single brake disk or the brake disks within whole vehicle shell model,for which the effect of the high temperature airflow from underhood on the brake disk dissipation performance is not considered,the dissipation performance of the ventilation brake disk of a SUV model with underhood parts is numerical calculated and analyzed. The outer flow field and temperature field,the surface convective heat transfer coefficient and the heat transfer power of the ventilation brake disk are obtained under different underhood heat generation condeions and vehicle velocities. The convective heat performance of brake disk can be improved with the increase of vehicle velocity under the same underhood heat source,but the dissipation performance of brake disk decreases with the increase of underhood heat source under the same vehicle velocity.