Fluid–Structure Interaction Analysis and Multi-Objective Optimization Design of Rectangular Microchannels

To tackle the degradation of heat transfer performance in microscale flows, an active regulation strategy based on structural parameter optimization is proposed in this study. Taking a microchannel heat exchanger as the research object, a parametric model is established by integrating multiple design variables, such as characteristic dimensions, channel height, and inlet flow rate. Subsequently, a multi-objective optimization framework is constructed, with the objectives of controlling average temperature, minimizing total mass, and maximizing heat transfer efficiency, while subject to the constraints of inlet flow rate and overall system pressure drop. By coupling computational fluid dynamics (CFD) simulations with intelligent optimization algorithms, the thermo–fluid–structure interaction mechanisms under the synergistic effects of various structural parameters are systematically investigated. The results demonstrate that a channel aspect ratio of 5:1 achieves superior comprehensive thermo-hydraulic performance, realizing the simultaneous improvement of heat transfer efficiency, suppression of pressure drop losses, and lightweight design of the system. This research provides theoretical guidance and a design paradigm for the thermal management of high-power-density microdevices.