Experimental Investigation of 3D Printed Polymeric Trifurcated Evaporators

Abstract Conventional finned-tube evaporators are commonly used in air conditioning systems, but their thermo-hydraulic performance could be potentially enhanced using advanced heat transfer topologies. The advent of additive manufacturing enables the design of such complex geometries, minimizing the thermal resistance between the hot and cold fluids for improved two-phase heat transfer performance. In this study, a nature-inspired 3D-printed trifurcated evaporator that mimics the bronchial architecture of the human lung is investigated. It features two interwoven fluid networks, resulting in enhanced flow distribution and significantly improved heat transfer efficiency. The performance of the nature-inspired evaporator is evaluated experimentally and compared against state-of-the-art finned-tube evaporators with 9.5 and 4 mm outer diameter tube configurations using a dielectric fluid as the evaporating working fluid. Results indicate that at an inlet superheat temperature of 24°C, a cold-side dielectric mass flow rate of 2.5 g/s, and a hot-side water mass flow rate of 12 g/s, the 3D-printed trifurcated evaporator demonstrates a thermal duty of 258 W, which is 84 and 322% higher compared to the traditional finned-tube evaporators with 4 and 9.5 mm outer diameters, respectively. Such significant improvements in the two-phase evaporation heat transfer rate offer a promising pathway for the design and development of next-generation evaporators for a myriad of two-phase thermal management systems.