Performance Analysis of Four Types of Adsorbent Beds in a Double-Adsorber Adsorption Refrigerator

Abstract

Four advanced types of adsorbent beds were designed, investigated and compared to each other in a double-adsorber adsorption refrigerator. The four types of adsorbent beds were assembled by several vehicle radiators with two different sizes. A prototype of the adsorption refrigerator built up in our laboratory was used to test the performances of the adsorbent beds. Silica gel-water was used as the working pair. The length, width and thickness of the radiators were measured. The amount of adsorbent filled into these four types of adsorbent beds was recorded. The dead area volume was estimated. The coefficient of performance (COP) and specific cooling power (SCP) of the system were tested after utilizing the four types of adsorbent beds. The COP and SCP of the four types of adsorbent beds were estimated under the standard operating condition and optimized operating condition. A SCP and a COP of the small-radiator adsorbent beds with 198.4W/kg and 0.30 were achieved under the optimized operating condition with 480 s adsorption/desorption time, 90 s heat and mass recovery time, 9 L/min hot water and cooling water flow rate, 2 L/min chilled water flow rate, 16°C chilled water inlet temperature, 90°C hot water and 25°C cooling water. Under the standard operating condition, the result showed that smaller dead volume leads to a slightly higher SCP. The adsorbent bed with smaller size radiator had a better heat and mass transfer ability and a higher SCP and COP could be achieved.