叶栅参数对液力缓速器起效特性影响规律研究

叶栅参数对液力缓速器稳态制动特性具有决定性影响，但其对动态制动特性、尤其是保证制动响应快速性的液力缓速器起效特性影响的研究鲜有涉及。为提升液力缓速器起效特性和保证行车安全，在给定负载惯量和充液方式时，构建液力缓速制动动态特性预测模型，通过对叶片表面压力分布积分预测动轮角速度和角加速度，获取起效过程制动转矩与转速随时间变化趋势，并由台架试验进行对比验证。通过给定不同动、定轮主叶栅及辅助叶栅典型参数配置，分析叶栅系统参数对起效特性及其轮腔内部流动状态变化的影响规律。结果表明，动、定轮主叶栅参数影响轮腔内部油液流动旋涡结构的衍生与发展，进而在起效特性上反映出峰值转矩与起效时间的差异。利用该方法能够为液力缓速器动态特性优化设计提供理论依据。

Research on the Influence Law of Cascade Parameters on the Onset Characteristics of Hydrodynamic Retarder

The cascade parameters have a decisive influence on the steady-state braking characteristics of the hydrodynamic retarder, but their influence on the dynamic braking characteristics, especially the onset characteristics of the hydrodynamic retarder to ensure the rapid braking response, is rarely involved. In order to improve the onset characteristics of the hydrodynamic retarder and ensure driving safety, the dynamic characteristics prediction model of the hydrodynamic retarder brake is constructed when the load inertia and charging mode are given. The angular velocity and angular acceleration of the moving wheel are predicted by integrating the distribution of the blade surface pressure, and the trend of the braking torque and rotation speed over time in the onset process is obtained, which is compared and verified by the bench test. Given the typical parameter configurations of the main cascades and auxiliary cascades with different moving and fixed wheels, the influence of the cascade system parameters on the onset characteristics and the changes in the internal flow state of the wheel cavity is analyzed. The results show that the main cascade parameters of the moving and fixed wheels affect the derivation and development of the vortex structure of the oil flow inside the wheel cavity, and the onset characteristics reflect the difference between the peak torque and the onset time. The prediction method in this paper can provide a theoretical basis for the optimal design of the dynamic characteristics of the hydrodynamic retarder.