Research on Leakage Characteristics of Thermoplastic Labyrinth Seals on High Pressure Differential

doi:10.3901/JME.2024.15.194

Abstract

Abstract: Wear-resistant and corrosion resistance thermoplastic material labyrinth seals can effectively reduce leakage. However, the research on leakage characteristics under large pressure difference is relatively few. Considering the interaction between seal ring deformation and flow field under large pressure difference, a three-dimensional bidirectional fluid-structure interaction model is used to analyze the internal flow field characteristics of the labyrinth seal, and the clearance changes and leakage characteristics under large pressure difference can be obtained. Labyrinth sealing experimental system is conducted, which can achieve a maximum pressure of 3 MPa. Under condition of large pressure difference, the low temperature caused by gas expansion is one of the key factors affecting the leakage. By analyzing the seal flow field characteristics, it is found that the actual flow cross-section of gas in the seal clearance is similar to the Laval nozzle structure, which can help the gas accelerate within the clearance. Blockage phenomenon occurs when the gas reaches the speed of sound at the final stage sealing clearance, which will lead to a significant increase in the flow field pressure in the final stage sealing groove. The solid model analysis shows that the sealing ring deformation caused by flow field pressure is also an important factor affecting the sealing clearance. Finally, the accuracy of the fluid structure coupling model is verified by experiments, and the maximum error between the calculated results and measured results is 6.2%.

Key words: labyrinth seals, leakage, two-way fluid-structure interaction, large pressure difference, blockage phenomenon

CLC Number:

TG156

LIU Yue, HUANG Min, LI Yongjian, AN Qi, JIANG Jie. Research on Leakage Characteristics of Thermoplastic Labyrinth Seals on High Pressure Differential[J]. Journal of Mechanical Engineering, 2024, 60(15): 194-204.

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