航天器用超低黏度齿轮泵关键参数研究

Research on Key Design Parameters of External Gear Pump with Lower Viscosity Medium Used in Spacecraft

为提高航天器用超低黏度齿轮泵的容积率和减轻泵的质量,基于泵周向和径向的两类主要泄漏,给出容积率的计算公式;以泵体积最小和容积率最大构建出双目标优化模型;针对只考虑内泄漏最小、综合考虑体积和内泄漏最小、只考虑泵体积最小的3种优化方案,分别进行优化计算并对相关参数的影响进行分析。结果表明,为适应介质的超低黏度,泵齿轮副的齿顶圆直径以及齿顶厚度应尽可能大,轴孔直径尽可能小;轴向间隙对泵容积率影响极大,为控制内泄漏之关键;过渡区采用无减少径向力措施的全齿密封,为提高容积率之最佳选择;较大的进油口和较小的出油口直径,利于提高泵容积率及避免因自吸力不足而造成泵的气穴现象。

To improve the volume rate of external gear pump with lower viscosity medium used in spacecraft and reducethe pump weight for launch cost down,the formula of volume rate was derived from the two main leakage of axial and ra？dial,and the double objective optimization model with minimum pump volume and maximum volume rate was constructed.Based on three kinds of optimization schemes,which are only considering the minimal internal leakage,considering theminimum pump volume and minimum internal leakage synthetically,and only considering the minimal volume,the optimi？zation was carried out respectively and the influence of relevant parameters was analyzed.The results indicate that,in orderto adapt to the lower viscosity medium,gear addendum circle diameter and gear addendum thickness of the pump shall beas large as possible,the axle hole diameter as small as possible.The axial gap has enormous influence on pump volume as large as possible,the axle hole diameter as small as possible.The axial gap has enormous influence on pump volumerate,and it is the key element for reducing the internal leakage.The best choice for increasing the volume rate is to use fulltooth seal without measures reducing the radial force in the transition zone.The larger inlet and smaller oil outlet diameter,is conducive to improve the pump volume rate,and avoid pump cavitations due to the insufficient suction.