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使用SiC网络陶瓷骨架增强的6061铝合金复合材料(SiCn/Al)制动盘可以减少高速列车的质量。采用有限元(FE)和计算流体动力学(CFD)方法计算在300km/h速度下实施紧急制动过程中考虑气流冷却条件下SiCn/Al制动盘的热和应力。分析制动器总成及其界面的设计特点时考虑了传导、对流和辐射这三种传热的模式。结果表明,具有较高对流系数的气流冷却不仅降低制动中的最高温度,也降低了温度梯度,因为气流加速了制动盘上较热部分的热量散失。有效的气流冷却可以减少制动盘上热斑的形成和盘体的热变形。有无考虑气流冷却时,实施紧急制动后,制动盘最高温度分别为461℃和359℃。有无考虑气流冷却时,制动盘的等效压力可分别达到269和164MPa。然而,在实施紧急制动时,制动盘表面的最大应力可能超过材料的屈服强度,这可能导致在不带冷却时制动盘的塑性损伤累积。模拟结果与实验结果相一致。
6061 aluminum alloy composite (SiCn / Al) brake discs reinforced with SiC mesh ceramic frame reduce the mass of high speed trains. The finite element (FE) and computational fluid dynamics (CFD) methods were used to calculate the heat and stress of SiCn / Al brake disks under the condition of airflow cooling in the emergency braking process at 300km / h. Analysis of brake assembly and interface design features consider the conduction, convection and radiation of these three modes of heat transfer. The results show that airflow cooling with higher convection coefficients not only reduces the maximum temperature during braking but also decreases the temperature gradient because the airflow accelerates the heat loss from the hotter part of the brake disc. Effective airflow cooling can reduce the formation of hot spots on the brake disc and the thermal deformation of the disc body. Whether or not to consider the air cooling, the implementation of emergency braking, the maximum brake disc temperature were 461 ℃ and 359 ℃. With or without air cooling, the equivalent disc brake pressures can reach 269 and 164 MPa, respectively. However, during emergency braking, the maximum stress on the surface of the brake disc may exceed the yield strength of the material, which may result in the build-up of plastic damage to the brake disc without cooling. The simulation results are consistent with the experimental results.