Research on Structural Design and End Face Slot of Optimization of Hydrodynamic and Hydrostatic Mechanical Seal

doi:10.3901/JME.2021.09.108

Abstract

Abstract: Aiming at the secondary utilization of mechanical seals for liquid rocket engines, this paper studied the structural design of the dynamic and static pressure mechanical seals and the optimization of the end grooves in order to avoid collision. Based on the principle of combined dynamic and static pressure, a dynamic and static pressure mechanical seal structure is designed, and the flow orifices in the static link and the dynamic pressure grooves in the dynamic ring are designed. The opening force and leakage of the static ring are solved based on the hydrodynamic equation. Based on the existing mechanical seal calculation software of the research group, the indicators such as the opening force and leakage of the moving ring were calculated. For the combined groove shape of the herringbone groove in the outer spiral groove, the geometry was optimized by orthogonal test. An optimal groove plan is determined. The trough optimization scheme has an opening force of 8.2 kN and a leakage volume of 0.66 mL / s. A larger opening force can be obtained on the premise of ensuring the leakage volume. The research results show that the mechanical seal in the form of dynamic and static pressure can effectively reduce wear during work, ensure a small leakage, and meet the requirements of secondary use. The research results can also provide a reference for the optimization of the mechanical seal structure of other high-speed rotating machinery.

Key words: rocket engine, turbopump, hydrodynamic mechanical seal, geometry, orthogonal experiment

CLC Number:

TB42

WANG Jianlei, MEN Chuanhao, ZHAO Weigang, JIA Qian, CUI Yahui, ZHANG Chen, YUAN Xiaoyang. Research on Structural Design and End Face Slot of Optimization of Hydrodynamic and Hydrostatic Mechanical Seal[J]. Journal of Mechanical Engineering, 2021, 57(9): 108-117.

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