车辆制动气室动态响应特性的无因次分析

Dimensionless Analysis of Dynamic Response Characteristics for Vehicle Brake Chamber

制动气室是车辆气压制动回路的关键组成部分,其动态响应特性直接影响车辆气压制动系统性能,建立制动气室充气过程数学模型,并通过实验验证模型的正确性。将制动气室的流量特性方程、状态方程以及活塞盘的运动方程无因次化,得到制动气室无因次解析模型,仿真计算出气室压力响应和运动特性变化规律。研究结果表明:制动气室回位弹簧满载弹力、橡胶膜片的膜片力等参数均会对气室响应特性造成不同程度影响,其中回位弹簧满载弹力的影响程度最大,但不同参数下气室的充气时间基本保持恒定。

A brake chamber is a key component of the vehicle pneumatic brake circuit,and its dynamic response characteristics affect the vehicle pneumatic brake system performances directly.Thus,researching the dynamic response characteristics of the brake chamber is important for defining the pressure response of the pneumatic brake circuit.Firstly,a mathematic model of the brake chamber charging process is established,and the correctness of the model is verified by the experiment.Then,based on the flow rate characteristics equation,the gas state equation and the piston motion equation,a dimensionless analytical model is established,and the change laws of the pressure response and the movement characteristic are calculated.The results indicate that:various parameters such as the spring full elasticity and the rubber diaphragm force affect the chamber response to different degrees;the influence of the spring full elasticity is the maximum,but the charging time of the brake chamber is constant under different parameters.