双联轴向柱塞泵配流盘优化与流量脉动特性分析

针对双联轴向柱塞泵配流盘在脱离吸油和排油时,柱塞腔存在闭死压缩和闭死膨胀阶段,造成柱塞腔气穴现象和压力正超调或负超调,引起流量和压力突变产生大的噪声问题,提出了一种配流盘结构。首先建立柱塞泵流动特性数学模型,分析轴向柱塞泵噪声产生机理;然后设计新配流盘结构并优化匹配三角阻尼槽结构参数,建立过渡区压力特性方程,通过理论模型对比分析,新配流盘能降低柱塞腔在过渡区产生的压力冲击。为了验证新配流盘结构对整泵流量和压力影响,采用液压仿真软件AMEsim建立双联柱塞泵模型,通过实验测试对比分析,验证了模型正确性。在相同工况下,将新配流盘和原配流盘代入整泵模型中,结果表明新配流盘流量脉动率比原配流盘流量脉动率降低了6.75%,证明新配流盘能很好地降低流体脉动。同时该模型为制造样机提供了理论基础,可降低新产品开发成本。

Valve Plate Improvement and Flow Ripple Characteristic Analysis for Double Compound Axial Piston Pump

The piston chamber has compression and expansion in closed volume when it is separated from the process of discharge and suction, which caused cavitations and pressure overshoot or undershoot. In addition, the noise problem caused by flow ripple and pressure pulsation may occur. Therefore, a new valve plate was designed to solve those problems. First of all, the mathematical model of flow characteristic was established to analyze the mechanism of the noise in axial piston pump. Then, the new structure of the valve plate was designed and the structure parameter of triangle notch was optimized. According to the design of valve plate structure, the equation of pressure characteristic in transition region was established. Thereafter, the new valve plate was capable to reduce the pressure pulsation, which was validated by theoretical calculation. Finally, the simulation model of piston pump was developed based on AMEsim to analyze the effects of the new valve plate on flow rate and pressure. Moreover, the simulation model was verified accurately based on the comparison of experiment and simulation results. The flow pulsation rate was calculated in the simulation model with original valve plate and new valve plate under the same working condition. The results showed that the flow pulsation rates with the new valve plate and original valve plate were about 11.47% and 18.22%, respectively, and the flow pulsation rate with the new valve plate was decreased by 6.75% compared with the original one. As a consequence, the results showed that the new valve plate can effectively reduce the fluid borne noise in the axial piston pump. The simulation model can be used in the design of new products, which can lower the cost.