Thermal–Hydraulic Performance and Material Sensitivity Analysis of Microchannel Heat Exchangers With AI‐Based Condition Monitoring Framework for Radar Transmit/Receive Module Cooling System

ABSTRACT In aerospace and defense industries, high‐power radar transmit/receive modules (TRMs) are often operated under extreme heat flux conditions, demanding compact and highly efficient thermal management solutions under size, weight, and power (SWaP) constraints. Due to high surface‐area‐to‐volume ratio and superior heat removal capability, microchannel heat sinks (MCHS) have emerged as a promising approach. Although MCHS provide enhanced heat transfer capability, pressure drop, substrate material sensitivity and long‐term operational reliability remain critical challenges in many cooling systems. This paper presents a combined analytical and computational investigation of the thermal and hydraulic performance of straight and zigzag microchannel heat sinks subjected to a 200 W heat load. Temperature dependent water properties are considered under laminar flow conditions (Re = 58–76). The influence of three substrate materials (Copper, Al6061, and SiC) on base temperature distribution and thermal spreading is evaluated. Numerical simulations are validated against analytical calculations, showing deviations below 1%. Results indicate that zigzag channels enhance local heat transfer but increase pressure drop by approximately 8% compared to straight channels due to bend‐induced flow resistance. Copper substrates reduce peak base temperature by up to 8% relative to Al6061 owing to superior thermal conductivity. A conceptual AI‐based condition‐based monitoring (CBM) framework is further proposed to enable predictive fault detection using pressure drop and thermal‐resistance indicators. The findings provide a physics‐based design reference for intelligent microchannel cooling architectures in high‐power radar systems.