Sealing Performance Of Separable Aviation Hydraulic Fittings

Separable aviation hydraulic pipe joints are important components in aerodynamic systems,and they are also frequent areas of sealing failure.Because the hydraulic pipes of aerodynamic systems are usually in a complex environment such as high temperature,high pressure and vibration.Once the sealing fails,it will affect the efficiency of the aerodynamic system,resulting in waste of resources and environmental pollution,even may cause fatal malfunction.Therefore,the sealing performance of aviation hydraulic pipe joints plays a crucial role in the safety and reliability of aerodynamic systems and aircraft.However,in practical applications,engineers and technicians mainly rely on experience to design the aviation hydraulic pipe joints,and their sealing mechanism is not yet fully studied.Therefore,it is of great theoretical significance and application value to carry out analysis of sealing characteristics of aviation hydraulic pipe joints.In this paper,the most commonly used cone-head and cone-hole sealing pipe joints and beam sealing pipe joints in aerodynamic systems are studied.Based on the sealing mechanism and the elasto-plastic contact theory,the contact pressure and the width of the sealing surface are the target parameters.The main structural parameters of pipe joints,assembly parameters and environmental factors on the sealing performance were analyzed through numerical simulation.Parametric modeling and automated analysis were introduced in this process to increase analysis efficiency.Through carrying out the above research,the sealing failure mechanism of aviation hydraulic pipe joints was explored,and the design basis,manufacturing guidelines and assembly requirements for sealing failure of the pipe joints were obtained to ensure the sealing reliability of the aviation hydraulic pipeline system.The detailed studies can be summarized as:1)Finite element verification of elasto-plastic contact theory.The Hertz contact problem is calculated and the theoretical results and numerical results are compared.The calculation results of different finite element software for cone-hole sealing pipe joints are compared to verify the reliability of ABAQUS elastic contact finite element calculations,providing the basis for theoretical and numerical calculations.2)Analysis of the sealing characteristics of cone-head and cone-hole sealing pipe joints.First,the finite element modeling and calculation methods for cone-shaped pipe joints are given,and the initial load is determined.Then using ABAQUS to carry out numerical simulation and calculate the relationship between the maximum contact pressure,the maximum Mises stress,the contact area,the width of the sealing surface and the parameters of the structure parameters,friction coefficient,etc.of the cone-head and cone-hole sealing pipe joints.According to the sealing conditions and the operating environment and requirements of pipe joints,the impact of various parameters on the sealing performance are analyzed,and a more robust range of parameters in the application of the project are given.3)Analysis of the sealing characteristics of beam sealing pipe joints.The finite element modeling and calculation methods for beam sealing pipe joints are also given first,and the initial load is determined.Then using ABAQUS to carry out numerical simulation and calculate the relationship between the maximum contact pressure,the maximum Mises stress,the contact area,the width of the sealing surface and the parameters of the structure parameters,friction coefficient,etc.of the beam sealing pipe joints.According to the sealing conditions and the operating environment and requirements of pipe joints,the impact of various parameters on the sealing performance are analyzed,and a more robust range of parameters in the application of the project are given.4)Develop an automated numerical analysis process for the sealing performance of pipe joints.Using Python language to build pipeline joint finite element model based on ABAQUS platform,and realize automatic numerical analysis of parametric model,which can reduce the modeling time of pipeline joint structure,and shorten the reanalysis cycle of structural numerical simulation.