Synopsis

International Journal of Mechanical & Mechatronics Engineering IJMME-IJENS Vol:13 No:01

60

Application of Evaporative Air Coolers Coupled With Solar Water Heater for Dehumidification of Indoor Air
A S Alosaimy
Mechanical Engineering Department, Faculty of Engineering, Taif University, KSA [e-mail] Abstract -- In the present work, novel configuration of solar powered desiccant dehumidification system is investigated. The proposed system comprises two evaporative air coolers. One of the two coolers functions as an absorber and the second, which is coupled with solar water heater, functions as a desiccant regenerator. In the experimental part of this investigation, Calcium Chloride is regenerated using solar energy. Hot water from a solar collector is circulated through an air heater to regenerate the liquid desiccant. Mathematical model, which can be applied for analysis of the proposed system, is developed. Absorption-regeneration cycle for the dehumidifier is described and analyzed. An expression for the efficiency of the simple cycle is introduced. Theoretical analysis shows that strong and weak solution concentration limits play a decisive role in the value of cycle efficiency. S ystem efficiency with consideration of heat and work added to the system is well defined. The limits of regeneration temperature and mass of strong solution per kg of produced vapor are found highly dependent on the operating concentration of desiccant. Experimental results show that solution with 30% concentration can be regenerated up to 50% using solar energy. Good agreement is found between the trained data of the ANN model and the experimental measurements for the whole range of the air inlet temperature.

Index Term--

Desiccant; humidification; absorption; air conditioning; Calcium chloride.

1. INTRODUCTION In hot and humid areas ,interest in utilizing solar poweredcooling systems for air-conditioning and refrigeration purposes has been growing

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