油液体积模量对液压机械全功率换段中目标段建压时间的影响

为了缩短液压机械全功率换段时间，基于全功率换段方法分析油液含气时的体积模量对目标段建压时间的影响。对油液正切体积模量进行理论分析和试验研究，获得油液正切体积模量的变化规律。以某两段等差式液压机械为研究对象，在全功率换段方法基础上，建立功率过渡阶段的目标段建压子过程模型。通过仿真分析与样机试验相结合的方法，得到考虑纯油液体积模量、油液含气时的正割体积模量和正切体积模量下的目标段建压时间。结果表明：当研究液压机械全功率换段的目标段建压时间时，必须考虑油液含气量对建压时间的影响，且应采用油液正切体积模量；油液含气量越大，油液正切体积模量越小，目标段建压时间越长。

Influence of Fluid Bulk Modulus on the Target Range Pressure Building-up Time of Hydro-mechanical Transmission in Full Power Shift

In order to shorten the power shift time of hydro-mechanical transmission (HMT), the influence of bulk modulus for the oil containing gas on pressure building-up time of target range is explored based on the full power shift method. The oil tangent bulk modulus is theoretically analyzed and experimentally studied, and the change law of tangent bulk modulus of oil is obtained. A two-range arithmetic HMT is taken as the research object. The target range pressure building-up model in the power transition stage is established based on the full power shift method. The pressure building-up time of target range under the conditions of secant bulk modulus, tangent bulk modulus and pure oil bulk modulus was obtained by means of simulation analysis and protogype experiment. The results show that, when studying the pressure building-up time of target range in full power shift, the influence of oil gas content on the pressure building-up time must be considered, and the tangent bulk modulus should be used. The larger the oil gas content is, the smaller the tangent bulk modulus is, and the longer the pressure building-up time of target range is. Key