15 September 2011


In the air-conditioning system, it is demanded to improve the APF (Annual
Performance Factor) that is defined in JIS standard. In the APF, CD value is needed for calculation of CSPF (Cooling Seasonal Performance Factor). CD value is constant to evaluate the performance degradation in small cooling load. This value affects the APF
greatly. In the current situation, as this value is defined to be constant, the manufactures can’t change this value to evaluate their product even though they develop the system whose part load performance is high. This obstructs the development of the higher performance
systems in small cooling load. Therefore, we try to develop new method to evaluate part load
efficiency. In this study, as a first step, CD value is actually evaluated, based on the simulation and experiment. As a result, the performance of the air conditioning system is changed greatly in the part load and CD value is not constant according to the driving conditions and control method.