| The hydro-pneumatic suspension has very high demands for the seal reliabilityconsidering its frequent movement and large shock. The performance of the suspensionsystem would be affected directly by the sealing system, whose glaring shortcomings wereoil spilling and low life which was frequently encountered by the designers and had beenone key technology at home and abroad. When designing the hydro pneumatic suspension,the choice for the sealing structure was a common problem, and what determined theselection and use was mostly the designer’s engineering experience and the test validation.Through the research into the sealing mechanism for the reciprocating dynamic seal of thehydraulic system, the thesis established the simulation model and performed the relatedsealing characteristics analysis on the basis of the MATLAB/SIMULINK platform and theABAQUS finite element software, which would provide some theoretical guidance fordesigners, reducing the number of test and shortening the development cycle.The paper had firstly prescribed the requirements of modern hydraulic control on thesealing system, and the domestic and foreign research status of the hydraulic sealingsystems was also mentioned, followed by the introduction of the concept, the classificationand the impact factor of the sealing.The material of the sealing element would weightily affect its performance, while theaccurate simulation for the material was considered as the research basis. Rubber materialsand synthetic plastics were common in our life and the former had superelasticity andnonlinear as its two typical characteristics. Using the experimental data, the correspondingcharacteristics were simulated accurately, obtaining the Mooney-Rivlin model parameters atthe same time.Domestic studies on hydraulic seals are mostly concentrating in the contact pressuredistribution and rarely discussing sealing performance such as seal leakage and friction.According to the basic theoretical knowledge of sealing this article builds mathematicalmodels of dynamic seal to calculate leakage and friction of reciprocating sealingperformance. The mathematical model of deformation of the sealing body based on the constitutive model of rubber materials as well as the basics of mechanics of materials, andthe seal gap flow model is established based on the basic knowledge of fluid dynamics.Because of the amount of deformation of sealing structure which commonly used inengineering is difficult to obtain by using mathematical methods, by means of ABAQUSfinite element software can accurately solving all kinds of sealing body deformation andcontact pressure distribution provides the basis for the study of the sealing performance.This article selects O-ring and combination seal, two commonly used sealing structurein piston rod seals, using finite element method to analyze sealing performance instationary and reciprocating working conditions. We obtained the distribution of stress andcontact pressure of the seal body by calculating, and in accordance with the mathematicalmodel obtained in the second chapter to solve the oil film thickness, leakage and friction.Change the sealing system state and structural design parameters based on the originalstructure of O-ring and combination seals, and analyze the impact on sealing performanceof changes in parameters. Analyze the impact of cross-section compression rate andworking pressure on the sealing performance of O-ring seals, and how pressure,reciprocating velocity and other parameters impact combination seals sealing performance.Finally, the fifth chapter summarizes the impact on sealing performance of changes inparameters of the simulation analysis, and hope to provide some theoretical guidance formethod of design and select reciprocating seals by using the work presented in this paper. |
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