Thermodynamic and Experimental Analysis of an Ammonia-Water Absorption Chiller

Dingfeng Kong, Jianhua Liu, Liang Zhang, Hang He, Zhiyun Fang

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DOI: 10.4236/epe.2010.24042                

Abstract

A single stage ammonia-water absorption chiller with complete condensation is designed, built and tested. The apparatus is designed for a cooling capacity of 2814 W, which is obtained using electric heater as heating source. The thermodynamic models have been derived using the First and Second Laws. Calculated results are compared with experimental data. The results show that the cooling capacity of experimental apparatus is found between 1900 and 2200 W with the actual coefficient of performance (COP) between 0.32 and 0.36. The contribution of the components to internal entropy production is analyzed. It shows that the larger irreversibility is caused by spanning the largest temperature and dissipated thermal energy by heat transfer losses at the generator and evaporator. In the experimentation, the low pressure is lower than the designed value. This is a consequence of a large capacity in the falling film absorber which performs as expected. This decreases the evaporation pressure, and the evaporating temperature could be reduced to the designed value.

Keywords

Absorption Chiller, Ammonia-Water, Thermodynamic Modeling, Experimental, Performance

Conflicts of Interest

The authors declare no conflicts of interest.

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