Performance Analysis Of Refrigeration System Used In Condenser With Liquid-vapor Separation

This paper experimentally investigated performance of an air conditioner matching with a parallel flow condenser employing vapor-liquid separation baffles for HCFC22 in air enthalpy method measuring equipment. The novel structure was composed of tube rows with a pair of manifolds at either end. A series of liquid-vapor separation were set in the manifolds, which not only divided refrigerant into several passes, but also had a function to automatically separate refrigerant condensate drain away from vapor-liquid mixture after each tube pass in time and hold annular flow, which made condensation always occur in an efficient mode. Moreover, the position of the baffles and the reasonable partitioning for the passes could achieve uniformity heat transfer in the whole condenser.A series of experiments was comparative study of liquid-vapor separation condenser (LSC) and the other three type condensers in an air conditioning system. It was the prototype "L" type condenser, the serpentine condenser and the parallel flow condenser without liquid-vapor separating capability. Influences of refrigerant charge amount, capillary tube length and heat source temperature on the whole air conditioning system were recognized and analyzed. The condensers were replaced directly and the other components such as condenser and evaporator of the air conditioner were unchanged.It was found that it can achieve the normal cooling capacity 2400 W and energy efficiency ratio (EER) 2.8 only with 63.1% heat transfer area of condenser and 80.3% refrigerant charge amount of the original one at the standard cooling condition during 1HP residential air-conditioning system. Compared with the prototype and serpentine condensers, the cooling capacity and EER of the LSC unit are reduced more significantly at undercharge conditions, yet the less reduction in performance is shown as it is overcharged. And other system performances such as discharge, suction pressure, mass flow rate, subcooling and superheat degree et.al had the similar trend.In the variation ambient conditions 29℃～41℃. The experimental results presented that mass flux in the novel condenser was greatest at the steady working conditions. Moreover, the LSC unit presented better performances compared to the prototype one on the lower operating conditions, but it could be performance outstanding compared with the serpentine one at the higher operating condition.No matter at what test range the units were, the pressure drops between inlet and outlet of condensers of the LSC were relatively smaller almost 50% even more than the normal one at the same operating condition.In addition, the more unapparent tube wall temperature fluctuation and the smaller difference wall temperature between inlet tubes of selfsame pass, which showed the more even distribution of flow within the LSC compared with the parallel flow one. The lower pressure drop and the better flow uniformity could make the condenser performance better in refrigerating system.