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为描述液力涡轮制动器内的流动特征及流动对制动器力矩性能的影响,采用计算流体动力学方法对制动器内的流动结构及空化现象进行了研究,获得了涡轮制动器瞬态启动和停止过程中转轮及挡板附近的流动参数分布,捕捉了制动器封闭腔体内的空化区位置和形态,求解了挡板上受到的流体载荷.结果表明,制动器腔体内存在着大尺度流动结构,其随着挡板与转轮之间的轴向距离增加而沿轴向发展;空化区出现在转轮叶片背面及根部附近,空化相体积份额随转轮转速增加而增大,但未对制动器的力矩系数造成明显影响;作用在挡板上的轴向流体作用力的合力方向始终指向转轮侧,该力的大小随转轮转速和叶轮与挡板间距增加而增加.“,”To depict the flow pattern and its influence on the torque performance of a hydraulic retarder,computational fluid dynamics technique is employed to explore the inner flow and cavitation phenomenon involved.Distributions of flow parameters in the vicinity of the rotor and the baffle during the start-up and stop process of the hydraulic retarder are obtained.Cavity position and morphology are virtually visualized in the closed retarder chamber.Hydraulic loads acting on the baffle are calculated as well.The results show that the large-scale flow structures exist in the retarder chamber.As the axial distance between the baffle and the rotor increases,these large-scale flow structures develop in the axial direction.Cavitation occurs near the back surface of the rotor blades and near the rotor hub.Cavitation volume fraction rises as the rotational speed of the rotor increases but exerts a moderate influence on torque coefficient.The direction of the resultant hydraulic force acting on the baffle always points towards the rotor,and the force magnitude increases with the rotational speed and the axial distance between the rotor and the baffle.