Fluid-solid Coupling Analysis Of Fully Liquid-filled Working Condition Of Torque-limiting Hydraulic Coupling

As a core component of large-scale mechanical equipment,the torque-limiting hydraulic coupling has a direct impact on the transmission efficiency of the equipment.The transmission performance is closely related to the shape change of the working cavity,so the analysis of its internal operating mechanism is very necessary.The current domestic research on the torque-limiting hydraulic coupling is still in the development stage,mainly on the internal flow field,pressure and vector distribution of the coupling and structural optimization design.There are few studies on fluid-solid coupling of torque-limiting hydraulic couplings,and the papers in this field abroad are in the state of encryption.Aiming at the reason why the D483 torque-limiting hydraulic coupling is continuously damaged under normal working conditions,it is judged that foreign objects have appeared in the working chamber during the working process of the coupling.Two explanations are made for the reasons for the appearance of foreign objects.Parts fall,the other is qualified blades that have no cracks or unqualified blades that have cracked for a long time and the blades fall due to the force of the working fluid.Therefore,the one-way coupled fluid-solid coupling method(FSI)was used to perform static analysis and comparison on the blades and to view the production date and time of production of the coupling.The phenomenon of energy consumption such as secondary flow backflow in the cavity.In the static calculation,the stress characteristics and deformation laws of the blade with increasing speed ratio are analyzed.According to the numerical calculation results,the continuous damage mechanism of the blade is compared,and the continuous damage to the impeller caused by the coupling part falling into the high-speed working chamber is analyzed.The main research contents and conclusions are as follows:(1)Theory and method of coupling field analysisBased on the cyclic symmetric structure of the torque-limiting hydraulic coupling,a suitable model is intercepted as a periodic structure model to reduce the requirements for memory and speed of calculation.In order to consider the accuracy and economy of the grid,for different quantities and Comparative analysis of quality grids,verification of irrelevance,and selection of appropriate grids;by comparing the advantages and disadvantages of various turbulence models,a suitable turbulence model is determined as the standard.And the convergence speed is fast;The data transmission between the pump wheel and the turbine is accurately transmitted by the sliding grid technology.(2)Flow field simulation calculation of the couplingThis paper analyzes the working point of the torque-limiting type hydraulic coupling under the full-filled working condition with different speed ratio.The geometric model of the coupling is established,the flow channel model is obtained by Boolean subtraction operation,and the periodic geometric model is intercepted;the turbulence model is used to obtain the velocity pressure and vector distribution in the working chamber under different operating conditions of speed ratio,and the work is accurately analyzed.The phenomena of energy loss such as secondary flow,backflow,and vortex in the cavity provide an effective way to optimize the structure of the coupling,and obtain its torque distribution characteristics,and find the energy loss in the torque transmission process.(3)Static calculation and analysis of the couplingIn order to study the force of the working fluid on the impeller,the unidirectional fluid-solid coupling analysis method is selected.The data results of the ANSYS Fluent flow field analysis are applied to the inner surface of the coupling working chamber as the external load of the STATIC Structural static analysis,and the pump The centrifugal load at the corresponding speed is applied by the wheel and the impeller,and the equivalent pressure and equivalent deformation of the coupler impeller are obtained through iterative calculation.Compare the maximum equivalent pressure value generated by the minimum speed ratio i=0 with the ultimate stress of the impeller material,and by looking at the production date and time of production of the damaged coupling.It is found that the material strength of the qualified blade without cracks meets the work of the coupling The coupling with strength requirements and damage is a qualified product that has just been put into production.It is analyzed that the coupling’s own parts fall into the high-speed working chamber and cause continuous damage to the impeller.