Structure Optimization Design Of Turbine Disk Based On Triply Periodic Minimal Surface

Turbine disk is the key bearing component of gas turbine,and its structural design directly affects the overall performance of the engine.However,the working environment of gas turbine disk is harsh,and it is in the environment of high temperature and high pressure for a long time.In order to improve the performance of gas turbine,engineers need to effectively reduce the weight of turbine disk in addition to meeting certain strength life and reliability requirements when designing turbine disk.Topology optimization is an advanced structural design method,which can obtain the optimal structure configuration through reasonable material distribution satisfying specified load conditions,performance and constraints.Pore structure has excellent physical and mechanical properties,and is widely used in lightweight design.In this paper,the turbine disk of a certain type of marine gas turbine is taken as the research object,combined with variable density method and pore structure design,the topology optimization research is carried out.In this paper,the optimal pore structure is first found and verified,and the mechanical properties of multiple pore structures are simulated and experimentally verified.Under the same boundary conditions,four pore structure static simulation and solid compression experiments were carried out,and the pore structure with the best mechanical properties was found through the combination of simulation and experiment,so that it could be embedded in the thick part of the turbine disc next.After finding the optimal pore structure,the focus of the work is to optimize the topology of the turbine disc of the research object.Firstly,the thermal-structure coupling theory is studied,and then the original model is structurally simplified,and the cyclic symmetry relationship constraint is applied according to the structural characteristics of the turbine disk,and the 1/6 model is simplified.Then,the working conditions and boundary conditions of the simplified model are analyzed,and the thermal-structure coupling simulation analysis and modal analysis are analyzed,which lays a foundation for the subsequent topology optimization.The theory of structural optimization is explained before topology optimization.Firstly,the lightweight design theory is summarized and elaborated,and the basic theory of variable density method is studied to lay a theoretical foundation for subsequent research and design.Then,on the basis of the coupled thermal-structural simulation analysis,the design space of the turbine disc is defined,the basic topology optimization parameters are set,and the topology optimization calculation is completed in ANSYS workbench.Structure reconstruction is carried out based on the topology optimization calculation results.At this time,the best pore structure found in the previous article is embedded in the part removed by topology optimization to obtain the optimized model.Then,the optimized model is coupled with the same thermal-structure as in the previous article to verify the rationality of the optimization scheme in this paper.Under the same constraint conditions and loads,the optimized turbine disk meets the requirements of stress strength and deformation,and reaches the preset design expectation.Compared with the quality of the original model,the overall weight of the optimized turbine disk model is reduced by 39.8%.It can be seen that the topology optimization design of the turbine disk is reasonable,and the lightweight design goal has been achieved.