Influence of the capillary pipe geometry on the energy efficiency of household refrigerator

University of Food Technologies, Plovdiv, Bulgaria, Department of MAFFT, Maritza 26, blvd.

^* Corresponding author: asimitchiev@gmail.com

Abstract

The energy efficiency of household refrigerating appliances was measured according to EN TSO15502. A Liebherr TKP 1650 built-in Domestic refrigerator is used to determine the influence of the capillary pipe geometry. The temperatures at the injection site of the refrigerant, the inlet and outlet of the evaporator receiver were measured. The obtained results show that there is no universal optimal geometry of the capillary pipe. There is no element of the refrigeration cycle whose change has no effect on the refrigerant flow rate passing through the capillary pipe. A change in the geometry of capillary pipe affects all other components of the refrigeration cycle and can greatly improve or impair the efficiency of the refrigerator. The potential for switching from one to two different geometries of the capillary pipe is approximately 8% improvement in energy consumption. Possible implementation should take into account the potential savings - 8% and the life cycle of the particular appliance (- 15 years). For the particular measured device, the consumption per year is about 75kWh, which should take into account that the device itself has a low volume and low energy consumption.