A methodology for the performance evaluation of an experimental desiccant cooling system

An experimental investigation was conducted in an open cycle desiccant cooling system (DCS) operating on the ventilation mode in the laboratory site [M. Yıldırım, An experimental investigation on heat and mass transfer in a desiccant cooling system, PhD thesis, Gaziantep University, Turkey (2002). [1]]. Although the operation of DCS is presumably affected by the design of primary components of rotary regenerator (RR) and desiccant wheel (DW) the methodology used in the analysis of experimental data is presented in this paper to set a different approach for the performance evaluation of similar systems. The rotational speeds of RR and DW (NRR and NDW), air mass flow rate (ma) in process and regeneration lines, and the regeneration temperature (TR) were defined as operation parameters. Meanwhile coefficient of performance (COP) and cooling capacity (CC) of the system were called as the performance parameters. The system operation with a variety of experimental conditions resulted in an extensive data set covering the ranges of NRR, NDW, ma and TR as 5 rpm ≤ NRR ≤ 20 rpm, 0.1 rpm ≤ NDW ≤ 0.4 rpm, 0.05 kg/s ≤ ma ≤ 0.139 kg/s and 60 °C ≤ TR ≤ 90 °C, respectively. The interactive influence of the operation parameters was determined through the realization of the psychrometric cycle in deviation from an ideal cycle. A dimensional analysis based on a trial and error procedure was followed to determine the functional relationship of COP and CC. The proposed correlations between COP and CC and the introduced system performance parameter (PP) were determined to be a sole function of ma independent of NRR, NDW and TR in their covered ranges.