Analysis The Three-dimensional Thermal Behavior And Tooth Surface Thermal Wear Of Filter Reducer Under Mixed Lubrication

The present work is funded by the Key Project of National Military in the Twelfth Five-year “Studies of High Rigidity and High Transmission Precision XXXX Device”,And the Key Project of National Natural Science Foundation of China “Basic Research of High-performance Spiral Bevel and Hypoid Gear Transmissions”(Grant No.51435001).Compared with foreign advanced reducers,there is still a huge gap between high precision reducer used in aerospace,weapons equipment,robotics and other fields independently developed by our country,mainly due to the contradiction between high precision and high stiffness,high load carrying capacity and the small volume.On the positive side,the above problems can be solved to a certain extent by the precision filter reducer,based on self-adaptive coordinated deformation according to the same principle of human functional joints.But the study on its high temperature behavior,thermal deformation,thermal failure and other problems is obviously insufficient,which caused by high/low temperature of envrionment,large torque,high speed and other severe working condtion.In order to improving carrying capacity and the adptations of precision reducers for extreme working conditions,such as high,low temperature and fluctuation of load and velocity,the analyses of thermal behavior and its temperature rise control are very necessary.Aiming at this point,this paper takes the precision filter reducer as the object,and on the basis of coupling the mechanism of friction heat generation,failure behavior of interal face and local temperature rise,puts forward the analysis method of thermal behavior of precision filter reducer and thermal wear analysis method of its interface.By the theoretical analysis and experimental verification,this thesis further enhances the understanding of thermal behavior and transmission interface failure of reducer.The main research contents are as follows:(1)Based on the multi-tooth elastic meshing behavior of the precision filter reducer,the load sharing is completed by taking the change of clearance angle between the meshing tooth pair and the meshing tooth pair,and the change of the meshing stiffness of different meshing position.The calculate results lay the foundation for improving the calculation accuracy of meshing interface friction heat flux and its distribution location.(2)Considering the load sharing and shear stress between the asperity and oil film of meshing surfaces in mixed lubrication,the nonuniform instantaneous heat flux of meshing teeth is calculated based the three-dimensional finite line contact.Furthermore,the local mesh transition and matching method is analyzed for achieving the instantaneous heat transformation form the mixed lubrication solution domain to the finite element model.And this transformation and movement of heat flux along the mesh line is realized by the subroutine DFLUX in the Abaqus/Standard step.(3)The convective heat transfer coefficient at different positions,the contact thermal resistance between contact pairs,and the friction power of bearing are analyzed in detail.The loading of the friction heat flux in the heat transfer model with whole reducer geometric is completed based on the local mesh transition and matching method and DFLUX.Next,the whole thermal behavior of the filter reducer and the instantaneous thermal behavior of the mesh surfaces are further studied by the finite element analysis method.The dangerous component of the reducer and its position are summarized from the distribution of high/low temperature field.By conduct the thermocouple temperature measurement experiment,the method of application equivalent heat load on the FEM to predicte the friction temperature rise is verified.(4)Becaue of the wear failure caused by the temperature rise of the interface friction must be different from the traditional wear failure analysis theory,the thermal wear model by the interface friction heat induction is proposed by taking the thermal softening effect caused by the temperature rise and the plastic strengthening effect caused by the deformation into the flow yield pressure of the material surface.The relationship between the traditional Archard model and the friction heat-induced material strength is determined.In order to verificate the the thermal wear model by the interface friction heat induction,ball-on-flat wear tests are carried out and the accuracy of the thermal wear model to predict siliding wear was verified by comparing the experimental and simulated wear profiles.Based on the thermal wear model combined with the transient temperature field analysis results of the internal gear teeth of the reducer,the thermal wear of the internal gear is calculated,and compared with the calculation results of the traditional Archard wear model,the wear and transmission of the precision filter reducer under the thermal wear theory are analyzed.Different under wear theory.