Numerical Simulation and Optimization of a Solar Adsorption Icemaker

Abstract

A solar adsorption ice maker was numerically studied. The system is an adsorption cycle that is connected to a separate solar heating system. An oil solar collector is connected to the generator of the adsorption cycle through a heat-exchanger in a closed loop. A refrigeration pair of Methanol-Activated Carbon (AC) was considered in the adsorption cycle. A mathematical model was developed for each component of the system. A transient numerical simulation was established, and the annual system performance was demonstrated under weather conditions of Makkah city, 21.5 N. The system unique design was achieved, and the ideal mass was predicted for the adsorbent and adsorbate together maintaining a constant percentage between them. It is found that the system which apply the Activated carbon/Methanol YKAC (14-20 MESH) might possibly deliver high solar system performance (SCOP) of about 0.26 during the cold days and 0.367 of cycle. As expected, lower temperature of the condenser and higher temperature of the evaporator can improve the system COP. In addition, three different kinds of collectors were considered and the maximum efficiency of about 0.80 was achieved for flat plate at optimum area of 3.15 m2 which is higher than both evacuated-tube (ETC) and parabolic trough collector (PTC) all over the year. The ETC efficiency is about 0.71 at ideal collector area of 3.5 square meters while the optimum area of the parabolic trough is 8.4 m2 at 0.79 of efficiency. In conclusion, the system results recommended that 22kg of ice could be produced every day for each square meter of solar collector.