Thermal-Fluid Simulation and Structure Optimization for Heat Dissipation of Submersible Pump Motors

Submersible pumps operate continuously under actual operating conditions, such as in mines and river dredging projects, where the heat dissipation performance of their built-in motors directly affects the equipment’s reliability and service life. To address the issues of insufficient heat dissipation efficiency and excessive motor temperatures in submersible pumps, this study conducts research on the optimized design of motor heat dissipation structures by integrating electromagnetic loss calculations, thermal-fluid coupled numerical simulations, and experimental validation. First, the Bertotti loss decomposition model and the finite element method were employed to calculate the electromagnetic losses during motor operation, which were then used as heat sources in the temperature field simulation. Subsequently, a thermal-fluid coupled numerical model of the motor was established to analyze the influence of different heat sink structural parameters on the motor’s temperature distribution. Based on single-factor simulations and orthogonal experiments, a heat sink structural optimization scheme was proposed, and the optimization results were validated through numerical simulations. The results indicate that under rated flow conditions, the optimized finned heat dissipation structure reduces the maximum motor temperature by 7.58 °C compared to the original design, significantly improving heat dissipation efficiency. Finally, a comprehensive testing platform for submersible pumps was established, and physical testing was conducted to verify the reliability of the numerical simulation results, with testing errors controlled within a reasonable range. The heat dissipation structure optimization scheme proposed in this study provides a theoretical basis and engineering reference for the thermal management design of submersible pump motors.