COP MESIN PENDINGIN REFRIGERAN SEKUNDER

Abstract

The aim of this Study was to determine the COPactual of the cooling machine model from secondary refrigerant in the load and no-load conditions.

The study was conducted in the laboratory. The cooling machine works with the vapor compression cycle, using R134a primary refrigerant and ethylene glycol secondary refrigerant. The Refrigeration machine is composed of main components such as power 1/5 HP compressor, a capillary tube diameter of 0.28 inches with a length of 2 m, with 12 U condenser, and evaporator 3/16 inch in diameter. There are 5 variations of LPG evaporator pipe length are 2.5 m, 3 m, 3.5 m, 4 m and 4.5 m. There are additional component filter cooling, temperature measuring devices and a pressure gauge. The refrigerant temperature data and pressure are used to describe the vapor compression cycle in p-h diagram. Enthalpy obtained from the p-h diagram, used to calculate the amount COPactual
cooling machine.

This Research results (1) The cooling machine secondary refrigerant can be used to freeze the results of marine products at the beach (evaporator temperature can reach: -26 0C and condenser temperatures can reach 60C). (2) COPactual for the entire length of the pipe evaporator variation for 8 hours of research moving in the range of 2.30 to 3.48 for no-load condition and in the range of 2.39 to 3.47 for load condition. (3) The average of COPactual for load condition has a greater
value than the COPactual for the no-load condition (4) For no-load conditions, the best average of COPactual owned cooling machine by using Lpe evaporator pipe length = 2.5 m, with a large 2,877 and for the load conditions, the best average of COPactual also owned a machine with a length of pipe evaporator using
Lpe = 2.5 m, with value 3.058.
Keywords: cooling machine , a secondary refrigerant, COP.