Experimental Investigation of Heat Pipe Embedded Cold Plates in Conduction Cooled Chassis

Conduction-cooled chassis have been extensively used in military applications for decades. With advancements in technology, the demand for higher performance and the miniaturization of electronic components has increased, leading to greater heat dissipation from smaller areas. Inefficient cooling of these components can result in performance degradation or permanent damage, making effective thermal management a crucial design criterion for conduction-cooled chassis. This study examines a 6U-sized electronic card with high heat dissipation and evaluates the thermal performance of heat pipe-embedded cold plates in a conduction-cooled chassis. The goal is to achieve a design that combines the lightweight properties of aluminum with the superior thermal performance of copper. Three versions of heat pipe-embedded cold plates were analyzed: one with heat pipes embedded on the non-contact rear surface, another with heat pipes embedded on the contact surface extending straight to the card edge, and a third design with heat pipes bent to increase the condenser area. Initially, the variations in thermal resistance based on wedge-lock mechanism torque were examined for aluminum and copper cold plates, resulting in the selection of 1.2 Nm as the optimal torque for subsequent tests. To comprehensively compare cold plates with varying weights and thermal performances, a weight-affected thermal performance criterion (WATPC) was introduced, which compares the weight of the cold plate to aluminum and its thermal performance to copper. The results indicate that heat pipe-embedded designs significantly enhance thermal performance while maintaining lightweight characteristics. These findings highlight the potential of such designs for high-performance, compact, and weight-sensitive applications, particularly in military and aerospace environments.