The Method Of Thermal Geometric Stability Design Based On Topology Optimization

With the comprehensive development of manufacturing technology, the level of manufacturing technology of high-precision manufacturing equipment is higher and higher. As high-precision manufacturing equipment, such as high-end CNC machine tools and basic manufacturing equipment,provide the platform for aerospace, automobile manufacturing, aircraft carrier, power generation equipment etc., developing the core technology and enhancing the capability of independent innovation is imminent. The working precision of high-precision manufacturing equipment as one of the important indicators to measure high-precision equipment performance, is a crucial evaluation index in design of high-precision manufacturing equipment.In this paper, to improve the precision of high precision equipment, considering the thermal working environment of high-precision equipment, choosing the thermal geometric stability as the objective, using the topology optimization techniques, the design of thermal geometric stability based on topology optimization is realized.a)This paper establishes a description of the thermal geometric stability and the objective of thermal geometric stability considering carrying capacity. For different engineering problems, different descriptions of the function and the objective function should be put forward. Strain energy on the structure as the objective and the displacement of a point as the objective is compared, leading to the thermal geometric stability problem.b)Based on the idea of topology optimization, topology optimization model and solution methods for the thermal conductivity of the flexibility constraint fully coupled carrying capacity in thermal geometric stability problems come out. Improve the precision of high-precision manufacturing equipment could start from the concept design, because a good concept model can provide an important guarantee for the follow-up of fine design. Topology optimization technology makes the idea of the concept design to become a reality. By the long-term practice and analysis, topology model has a great influence on the topology results. So, this paper studies how to make the appropriate topology optimization model, and proposes the thermal geometric stability in stiffness constraints as the objective, choosing the key points in the high-precision manufacturing equipment (such as high-end CNC machine tools, machining heads) as feature points. Feature points’displacement in the thermal environment is chosen as the objective, and the comparison between the traditional flexibility-objective and the new thermal geometric stability-objective is conducted in this paper. The model is verified validity and correctness.c)Design the structural configuration of the thermal geometric stability problems in fixed temperature environment. Use the model of given temperature field in a given area to describe the temperature changes in the environment. In this way, finite element equation includes coupled temperature and mechanical loads coupled, and this coupling is also present on the sensitivity of the objective function for solving.d) Design the structural configuration of the thermal geometric stability problems in fixed temperature boundary condition. Use the model of given heat source and thermal boundary conditions to describe the changes in thermal environment. On the basis of the front of a model, heat transfer equations would be solved, leading to the sensitivity of the objective for solving more complex. For facilitate comparison, unified interpolation scheme and optimization algorithm are used-the solid isotropic material with penalization (SIMP) and SLP algorithm.This work is supported by the National Basic Research Program of China (2011CB610304), National Science and Technology Support Program (2011BAF11B03), Major science and technology projects (2012ZX04010-011)...