Modeling and thermal characteristic analysis of feed system considering multi-physical field coupling

Abstract

The feed system (FS), a critical component in machine tools, significantly impacts machining accuracy through its thermal characteristics. Accurate modeling of its contact mechanism and coupled physical fields is essential for determining precise boundary conditions (BCs), which are fundamental to thermal characteristic modeling. To address this, this study proposes a fluid-solid-thermal coupling strategy to calculate the BCs integrating film-structure-temperature, convection-structure-temperature, and thermo-mechanical coupling. This strategy is built on a contact mechanism model (RCCD-CF-GM-ARCT) incorporating raceway curvature center displacement, centrifugal force, gyroscopic moment effects, and adaptive raceway control theory. Subsequently, the thermal characteristic model (TC-MPFC-HM) is developed using the finite element method, based on the multi-physical field coupling strategy and the moving heat of the FS. Additionally, a closed-loop iteration algorithm is proposed to dynamically update BCs, ensuring accuracy and responsiveness. The results show significant improvements over traditional models, reducing RMSE by 77.54%, 82.81%, and 85.17%, and MAE by 78.4%, 82.06%, and 86.41% under various working conditions. These results validate that the model has enhanced precision and robustness, offering a comprehensive approach for thermal error modeling of FS.