基于FLUENT的高压高速螺旋转子泵内部流场分析

Internal Flow Field of Helical Rotor Pump at High Speeds and High Pressures Based on FLUENT

目的分析高压高速螺旋转子泵运行过程中的内部流场行为,为高压高速螺旋转子泵的结构优化提供理论依据。方法利用Solid Works建立高压高速螺旋转子泵三维模型,使用FLUENT仿真其在高压高速运行条件下的内部流场,得到压强云图,对比有、无气穴时转速对油膜最大压强和最大负压影响。结果气穴对高压区的啮合压强基本没有影响。齿轮啮合处压强最大值、齿轮啮合处负压最大值及空气在液压油中的占有率随转速的增加而增大,当转速为12 000 r/min时,空气占有率高达12.81%,啮合处的压强可高达37.5 MPa,是出油口压强的1.5倍。结论气穴阻止了部分齿顶间隙的泄漏,对转子稳定性的提高有积极意义。最大压强出现在螺旋转子泵转子的啮合处,这使转子产生了剧烈振动,降低了螺旋转子泵的稳定性。

The work aims to analyze the behavior of internal flow fields when the helical rotor pump（HRP） is operating at high speeds and high pressures, which provides theoretical basis for the structure optimization of such HRP. The 3 D model of HRP at high speeds and high pressures was established with Solid Works. FLUENT was applied to simulate the internal flow fields of HRP operating at high speeds and high pressures to obtain the contours of pressure. The influences of speed on the maximum pressure and the maximum negative pressure of oil film with and without cavitation were compared. Cavitation had little effect on the meshing pressure in the high-pressure area. The maximum pressure and the maximum negative pressure at the gear meshing part and the occupation of air in the hydraulic oil were increased with the increase in the rotation speed. When the speed was 12 000 r/min, the air occupation was up to 12.81% and the pressure at the meshing part could reach up to 37.5 MPa, which was 1.5 times the size of pressure at the oil outlet. The cavitation prevents the leakage of partial gear tip clearance, which has positive significance for the improvement of rotor stability. The maximum pressure appears in the area where the HRP rotor meshes, which causes the rotor to generate dramatic vibration and reduces the HRP stability.