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

IF 2.1 3区工程技术 Q2 ENGINEERING, AEROSPACE

Aerospace Pub Date : 2023-12-29 DOI:10.3390/aerospace11010040

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

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引用次数: 0

Abstract

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.

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基于实验和数值模拟的圆柱形气膜密封微间隙流场特性研究

柔性支撑圆柱形气膜密封（CGFS）能很好地适应转子的旋转，在热变形过程中具有良好的气体润滑效果。然而，当 CGFS 在 "三高"（高界面滑移速度、高压差、高环境温度）工况下运行时，支撑结构的复杂变形是影响 CGFS 稳定性的关键因素。全面系统地分析柔性支撑 CGFS 的微隙流场特性，是我们研究支撑结构在多种物理场条件下变形的一个基本问题。本研究利用圆柱形气膜高速转子试验台对实验和数值模拟的密封特性进行了研究和比较，并对模拟模型的准确性和有效性进行了优化和验证。采用跨尺度气膜网格模型分析不同沟槽模型的流场特性和密封能力，并比较其机械特性和密封性能。我们还分析了微间隙中的气膜压力分布，并探讨了动压沟槽微结构对流场特性的影响。结果表明，微间隙是产生流体动力效应的主要条件，高转速、高压差和大偏心率对改善流体动力效应和提高气膜稳定性有显著作用。然而，这些参数的增加会导致泄漏率的增加。单流道更容易改善流体力学效应、气膜承载能力和气膜稳定性，同时降低泄漏率。本研究的分析补充和完善了圆柱环形微间隙流场特性理论，为探索 CGFS 的支撑结构参数与微间隙流场力学特性之间的关系提供了理论依据。该研究为建立支撑结构定量设计理论提供了重要指导。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Aerospace ENGINEERING, AEROSPACE-

CiteScore

3.40

自引率

23.10%

发文量

661

审稿时长

6 weeks

期刊介绍： Aerospace is a multidisciplinary science inviting submissions on, but not limited to, the following subject areas: aerodynamics computational fluid dynamics fluid-structure interaction flight mechanics plasmas research instrumentation test facilities environment material science structural analysis thermophysics and heat transfer thermal-structure interaction aeroacoustics optics electromagnetism and radar propulsion power generation and conversion fuels and propellants combustion multidisciplinary design optimization software engineering data analysis signal and image processing artificial intelligence aerospace vehicles'' operation, control and maintenance risk and reliability human factors human-automation interaction airline operations and management air traffic management airport design meteorology space exploration multi-physics interaction.