الفهرس | Only 14 pages are availabe for public view |
Abstract In the present work, activated carbon/methanol used as a working pair because of the high compatibility between them as common adsorption working pair, and also suitable for solar energy due to its low desorption temperature. Activated carbon–methanol system can be powered by low-grade heat (70–100 °C). Several advantages of methanol like the high latent heat of evaporation, low freezing point, and no corrosion to copper and steel at the working temperature below 100 °C make it reliable and working well with activated carbon. Based on low-grade temperature utilization, solar energy can be positively utilized in such systems. This work aims to make an experimental investigation of the thermal performance of an activated carbon-methanol adsorption refrigeration system to study the effect of the enhanced thermal conductivity of the adsorbing bed. Using 0%, 10%, 20 %, 30% of metallic copper powder with activated carbon to enhance the thermal conductivity of the bed, providing a significant improvement in the system efficiency, specific cooling power (SCP), and coefficient of performance of adsorption cooling. It is found that copper filing with a mass concentration of 20% are appeared the optimal ratio metallic additive to enhance the thermal performance of the system. Moreover, the effect of the hot water flow rate is studied. Results indicated that the addition of 20 % metallic copper filings to the activated carbon lowered the evaporator temperature to reach -5 and -10 °C for heating water flow rates 3 and 2 LPM, respectively. Also, the addition of copper filing enhances the cycle COP of the system by 49% and 46% at hot water flow rates of 3 and 2 LPM, respectively. The highest cycle COP of the current system reached was 0.92 for the condition 20% additives at 2 LPM hot water flow rate. Owning the feature of great solar energy availability and the long daily sunny hours, solar-powered adsorption cooling systems have promising potential applications in Egypt. A mathematical model of the system performance is also studied. And used the simulation program. The thermal performance of the solar adsorption cooling system was carried out through the evaluation of the COP of the adsorption chiller under different solar collector types. The parabolic trough concentrator (PTC), the compound parabolic concentrator CPC), and the flat plate solar collector (FPC) were selected to investigate its effects on the COP of the absorption chiller. |