Design, Fabrication, and Testing of a Polymer Expanded Heat Exchanger for Absorption Chilling

Abstract

The increasing demand for energy-efficient and environmentally friendly cooling technologies has driven the exploration of advanced heat exchanger (HX) designs. Traditional metal HXs, while effective, are often heavy, expensive, and prone to corrosion. This study addresses these challenges, presenting the design, fabrication, and testing of a polymer expanded heat exchanger (PEHX) for a high-pressure, water–ammonia–helium absorption refrigerator. Utilizing open-source laser welding and 3D printing, the PEHX was constructed from linear low-density polyethylene and acrylonitrile butadiene styrene. The PEHX achieved an effectiveness of 0.62, a 13% improvement over the existing heat exchanger's 0.55, potentially reducing the refrigerator's power consumption by 5 W. Over a 10-year lifespan, this could save approximately 453 kWh of energy, equivalent to electricity costs of $68 and greenhouse gas emissions of 321 kg(CO2,e). However, the PEHX exhibited a higher pressure drop than the existing heat exchanger, necessitating further design improvements, including optimized welding techniques, alternative flow patterns, and redesigned headers to reduce pressure drop. This work demonstrates the potential of additive manufacturing of polymer heat exchangers for applications requiring lightweight, cost-effective, and corrosion-resistant heat transfer solutions, and highlights areas for future research.