Research on Micro Gap Flow Field Characteristics of Cylindrical Gas Film Seals Based on Experimental and Numerical Simulation

Zhen Xu; Lianjiang Xu; Junfeng Sun; Meihong Liu; Taohong Liao; Xiangping Hu

doi:10.3390/aerospace11010040

Aerospace (Dec 2023)

Research on Micro Gap Flow Field Characteristics of Cylindrical Gas Film Seals Based on Experimental and Numerical Simulation

Zhen Xu,
Lianjiang Xu,
Junfeng Sun,
Meihong Liu,
Taohong Liao,
Xiangping Hu

Affiliations

Zhen Xu: Faculty of Mechanical and Electrical Engineering, Yunnan Open University, Kunming 650500, China
Lianjiang Xu: Faculty of Mechanical and Electrical Engineering, Yunnan Open University, Kunming 650500, China
Junfeng Sun: Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunming 650504, China
Meihong Liu: Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunming 650504, China
Taohong Liao: Department of Marine Technology, Norwegian University of Science and Technology, 7491 Trondheim, Norway
Xiangping Hu: Industrial Ecology Programme, Department of Energy and Process Engineering, Norwegian University of Science and Technology, 7491 Trondheim, Norway

DOI: https://doi.org/10.3390/aerospace11010040
Journal volume & issue: Vol. 11, no. 1
p. 40

Abstract

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Flexible support cylindrical gas film seals (CGFSs) adapt well to rotor whirling and have a good gas lubrication effect during thermal deformation. However, when a CGFS operates under the “three high” (high interface slip speed, high-pressure differential, and high ambient temperature) operating conditions, the complex deformation of the support structure is a crucial factor affecting the stability of the CGFS. A thorough and systematic analysis of the micro gap flow field characteristics of flexible support CGFSs is a fundamental problem when we study the deformation of the support structure under multiple physical field conditions. This study uses a cylindrical gas film high-speed rotor test rig to study and compare the sealing characteristics of experiments and numerical simulations and then optimizes and verifies the accuracy and effectiveness of the simulation model. A cross-scale gas film grid model is used to analyze the flow field characteristics and seal ability of different groove models and compare the mechanical characteristics and sealing performance. We also analyze the gas film pressure distribution in micro gaps and explore the impact of dynamic pressure groove microstructure on flow field characteristics. Results show that micro gaps are the primary conditions for generating hydrodynamic effects, and high rotational speed, high-pressure differential, and large eccentricity have a significant effect on improving hydrodynamic effects and enhancing gas film stability. However, an increase in these parameters can cause an increase in leakage rate. A single flow channel makes it easier to improve the hydrodynamic effect, gas film load-bearing ability, and gas film stability while reducing leakage rate. The analyses in this study supplement and improve the theory of the flow field characteristics of cylindrical annular micro gaps and provide a theoretical basis for exploring the relation between the support structural parameters of the CGFS and the mechanical characteristics of the micro gap flow field. This study provides important guidance to the establishment of a quantitative design theory of supporting structures.

Published in Aerospace

ISSN: 2226-4310 (Online)
Publisher: MDPI AG
Country of publisher: Switzerland
LCC subjects: Technology: Motor vehicles. Aeronautics. Astronautics
Website: http://www.mdpi.com/journal/aerospace

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