Performance of solid desiccant-based evaporative cooling system under the climatic zones of India

For better use of evaporative cooling techniques in humid climate, a desiccant cooling system (DCS) can be an alternative option in place of a conventional cooling system. This paper presents a theoretical comparative study of the performance of a DCS for four different climatic conditions of India (i.e. hot and dry, warm and humid, moderate and composite climates). From the analysis, it was found that the performance of a DCS is suitable in warm and humid climate. The thermodynamic equations of intermediate states of the desiccant cooling cycle are also presented. Effects of some parameters such as outdoor specific humidity, R/P ratio (regeneration air flow/process air flow) and power required to regenerate the desiccant wheel have been studied. The theoretical minimum R/P ratio has been computed for the maximum coefficient of performance (COP) of a DCS and its value was found to be 0.55 in Mumbai (warm and humid climate) for the 80% effectiveness of ECW. This paper also presents the relationship between COP and regeneration power with the different values of R/P ratios.