| In order to solve the problem of large pressure loss and limited optimization space of traditional hydraulic channel,this topic adopts Selective Laser Melting technology(SLM)combined with fluid topology optimization method to optimize the design of hydraulic channel.Aiming at the hydraulic channel with large local pressure loss caused by the change of flow velocity direction and flow field section,the topology optimization of the three-dimensional flow field of the hydraulic channel is carried out with the minimum pressure loss between the inlet and the outlet as the optimization objective,and the influence law of flow field structure on pressure loss is explored.The optimized channel and manifold block are formed by SLM technology.The main research work of this paper is as follows:In the first chapter,the research status of hydraulic channel and its optimization design and the forming principle of SLM technology are introduced,the research status of forming hydraulic manifold block by SLM technology is summarized,the topology optimization method is introduced and the related background of fluid topology optimization is introduced.Finally,the significance and main research contents of this study are expounded.In the second chapter,the fluid topology optimization method used in this paper is introduced,and the fluid topology optimization of the flow fields with right-angle turning channel,"Z"-shaped channel,"U"-shaped channel and "Y"-shaped channel,commonly used in hydraulic manifold blocks is carried out.Through simulation,compared with the flow fields designed by traditional machining and arc transition optimization,the results show that the pressure loss of the flow fields after topology optimization is the smallest.Then,reverse modeling and surface offset are used to increase the uniform wall thickness for the topology optimization flow field to obtain the channel solid model.In chapter 3,the causes of local pressure loss in the channel are analyzed,mainly including vortex region and secondary flow.By simulating and comparing the flow fields with sudden contraction,sudden expansion and right-angle turning with those with topology optimization,it can be seen that the vortex area disappears and the pressure loss is reduced.For the secondary flow in the turning channel,the influence law of Dean vortex,the main form of the secondary flow,is analyzed by numerical simulation,and the bending degree of the flow field structure is improved to reduce the influence of Dean vortex on pressure loss.In the fourth chapter,the topology optimization design of the internal flow channel of the vehicle posture adjustment manifold block is studied,and the topology optimization results of some flow fields are analyzed,which is verified by the influence law of Dean vortex obtained in the third chapter,showing the superiority of topology optimization of flow field structure.Topology optimization design and simulation of manifold block internal flow channel show that the pressure loss is reduced by more than 24% compared with the flow channel model of preliminary optimization design,and by more than 66% compared with the internal flow channel of manifold block processed by traditional methods.In chapter 5,the forming equipment used in this paper,the characteristics and printing parameters of 316 L stainless steel powder are introduced,and then the flow channels and manifold block of topology optimization design are printed and formed,and the vehicle posture adjustment manifold block manufactured by traditional processing and SLM forming are tested experimentally respectively.Chapter six summarizes the work of this paper and looks forward to the next step. |
