基于流热固多物理场耦合的电主轴热误差建模研究

Research on Thermal Error Modeling of Electric Spindle Based on Fluid Thermal Solid Multiphysics Coupling

摘要: 针对电主轴热误差仿真建模中忽略冷却液自身的温度变化对冷却效果的影响，导致预测精度不准确的问题。建立流–热–固多物理场耦合有限元模型，在热–结构耦合模型中引入流体域，通过流–固交界面将冷却液的温度场作为热分析中螺旋冷却管道的精确热边界条件、压力场作为结构分析中的力约束，更为真实地反映冷却液的实际换热能力和螺旋冷却管道的实际受力情况。采用基于热流密度的载荷施加方式与流–热–固多物理场耦合方法相结合的ANSYS仿真模型，仿真结果表明电主轴最大轴向热变形为51 μm，与实验测得的值相比，残差在5.2 μm左右。可以有效地实现高速电主轴热误差预测。

Abstract: In the simulation modeling of thermal errors in electric spindles, the influence of the temperature change of the coolant itself on the cooling effect is ignored, resulting in inaccurate prediction accu-racy. Establish a fluid thermal solid multi-physics coupling finite element model, introduce a fluid domain into the thermal structure coupling model, and use the fluid solid interface to treat the temperature field of the coolant as the accurate thermal boundary condition for the spiral cooling pipeline in thermal analysis, and the pressure field as the force constraint in structural analysis. This more accurately reflects the actual heat transfer capacity of the coolant and the actual stress situation of the spiral cooling pipeline. The ANSYS simulation model combines the load application method based on heat flux density with the fluid thermal solid multi-physics coupling method. The simulation results show that the maximum axial thermal deformation of the electric spindle is 51 μm. Compared with the experimentally measured values, the residual is 5.2 μm around, it can more accurately predict the thermal error of the electric spindle.