Optimization of Absorption Refrigeration Systems by Design of Experiments Method

The objective of this work is to present an energy analysis of different absorption refrigerating systems operating with diverse refrigerants. Also we apply the method of experimental design to optimize configurations proposed by the absorption pairs used and the operating conditions. We focus on both acceptable COP and low operating generator temperature. Therefore, a computer program is developed. An investigation of the thermodynamic properties is presented. Results show the COP evolution versus respectively the evaporator temperature, the temperature of condensation and the generator temperature. A particular interest is accorded to the intermediate pressure effect on the performance of the different systems. In order to better converge in the selection of the configuration and the refrigerant, which can ensure a high COP associated to relatively low operating generator temperature we have developed an experiments design, taking in account all parameters influencing the system performance and the operating function temperature. Results show that the refrigerating machine containing a compressor between the evaporator and the absorber has a coefficient of performance quite acceptable and that it can work at low generator temperature for about 60°C and using the NH3/LiNO3 as refrigerant.