Research on Wire Harness Temperature Rise Design Technology for Aircraft Based on Flow-Thermal Coupling

Ten thousand of wires on an aircraft must be integrated into several hundred wire harnesses. The number of wires, arrangement methods, and combinations of wire specifications in each bundle are highly variable, forming complex bundle configurations. The temperature rise of these wire harnesses is a key technical factor in the design of the aircraft's Electrical Wiring Interconnection System (EWIS), affecting the safety, reliability, and cost-effectiveness of the system. Existing methods based on standard current-carrying capacity do not meet the requirements for complex scenarios, while analytical methods have significant errors, and finite element method (FEM) is complex and inefficient. Therefore, this paper proposes a flow-thermal coupling method that combines FEM and analytical calculations for temperature rise computation in wire bundles. Based on studies of factors such as bundle arrangement, wire count, and bundle slackness, the model solves the convective heat transfer system for the wire bundle by FEM, then incorporates it into analytical formulas to establish a flow-thermal coupling model. Results are compared with experimental measurements and standard values to confirms the correctness of the flow-thermal coupling method.