变转速工况对直线共轭内啮合齿轮泵容积效率的影响

随着液压技术向高压化、轻量化、节能化发展，直线共轭内啮合齿轮泵因具有结构紧凑、流量脉动小、使用寿命长、噪声小等优点，其应用领域逐步扩大。随着内啮合齿轮泵使用转速的变化，其容积效率也出现变化，为了获得内啮合齿轮泵转速对其容积效率的影响规律，采用液压油、纯水两种介质，通过数值计算的方法，研究内啮合齿轮泵转子域空化特性、对比分析出口体积流率。结果表明：随着转速上升，内外齿啮合最小容积腔及吸油口处气相体积分数增加明显，易引起空化、气蚀，从而产生噪声、振动等问题；当转速过高时，介质中的气体析出明显，易出现吸空现象，导致齿轮泵容积效率降低，纯水介质比46#液压油介质下的齿轮泵容积效率更低。因此，要改善高转速工况下的齿轮泵容积效率，需优化内啮合齿轮泵进油口流道，增加入口压力，提升内啮合齿轮泵高转速工况下的综合性能。

Influence of Speed on Volumetric Efficiency of Linear Conjugate Internal Gear Pump

With the development of hydraulic technology to high pressure, light weight and energy saving, the linear conjugate internal gear pump has the advantages of compact structure, small flow pulsation, long service life and low noise, and its application field is gradually expanding. With the change of the operating speed of the internal gear pump, its volumetric efficiency also changes. In order to obtain the influence of the internal gear pump speed on its volumetric efficiency, this paper uses two media, hydraulic oil and pure water, through the numerical calculation method, The cavitation characteristics of the rotor region of the internal gear pump were studied, and the outlet volume flow rate was comparatively analyzed. The research results show that with the increase of the rotational speed, the gas phase volume fraction at the inner and outer teeth meshing minimum volume cavity and the oil suction port increases significantly, which is easy to cause cavitation and cavitation, resulting in noise, vibration and other problems; when the rotational speed is too high, the gas in the medium The gas evolution is obvious, and the phenomenon of air suction is easy to occur, which leads to the reduction of the volumetric efficiency of the gear pump. The volumetric efficiency of the gear pump in the pure water medium is lower than that of the gear pump in the 46# hydraulic oil medium. Therefore, in order to improve the volumetric efficiency of the gear pump under high speed conditions, it is necessary to optimize the oil inlet flow passage of the internal gear pump, increase the inlet pressure, and improve the comprehensive performance of the internal gear pump under high speed conditions.