Conjugate Heat Transfer Modeling for Predicting Thermal Behavior of X76 Emotor Windings

A computational study based on a conjugate heat transfer (CHT) method in SimericsMP+ was performed to predict the winding temperatures in an X76 emotor. In this study, the thermal load was represented in the simulation through the solution of electromagnetic equations in SimericsMP+, where heat generation was driven by root-mean-square (RMS) current, while liquid cooling was applied at flow rates ranging from 1 LPM to 6 LPM. Simulations were conducted to measure the temperature on three thermocouple locations on each side of the winding crown and weld regions under steady operation. The computational strategy employed a loosely coupled approach. A fluid-only simulation was first carried out to establish stable flow conditions, followed by coupling with solid conduction where the winding acted as the heat source. The predicted temperature distributions were then compared with test data. Results obtained show good agreement, with differences remaining within an acceptable range, thereby confirming the accuracy of the numerical method. Findings demonstrate that the CHT approach not only reproduces measured winding temperatures but also provides detailed insight into local flow and temperature fields inside the emotor, information not accessible through physical testing alone. The validated methodology offers a reliable tool for guiding thermal management design and optimization of electric machines under varying cooling conditions.