Real Air-Conditioning Performance of Ejector Refrigerator Based Air-Conditioner Powered by Low Temperature Heat Source

Abstract

In this present work, the air-conditioning test performance of an ejector refrigerator-based air-conditioner (ERAC) was proposed. The ERAC was operated as the water chiller to produce the cooling load up to 4.5 kW. The chilled water temperature was later supplied to the fan-coil unit for producing the thermal comfort condition. The cooling water used to cool the condenser was achieved from the cooling tower which was operated under the hot and humid ambient. This is to demonstrate the feasibility of using the ERAC in real working conditions. The cooling load supplied to the air-conditioned space was applied by the air heater. The ERAC could efficiently be operated to produce the thermal comfort condition which was driven by the hot water temperature (Thot) of 90–98 °C. The system performance could vary with the heat source temperatures, cooling load, primary nozzle, and air-conditioned space temperature. The optimal performance was determined when varying the Thot, and, hence, the optimal Thot was indicated. The optimal Thot varied significantly with variations in the working condition. The test results demonstrated high potential to further using the ejector refrigeration system in the actual air conditioning application.

Experimental Determination of an Optimal Performance Map of a Steam Ejector Refrigeration System

“…This is consistent with the steam ejector refrigerator powered by a solar evacuated tube collector in a warm climate (such as Thailand). In such a case, the cooling water of around 27-34 • C is produced for operating the refrigerator as supported by Ruangtrakoon and Thongtip [23] and Thongtip and Aphornratana [34].…”

“…Another advantage of using steam as the working fluid over modern refrigerants is that the waste steam or steam tab from industrial boilers can be directly used to drive the ejector, while for the refrigerant, the heat exchanger is required to generate refrigerant vapor to operate the ejector. Thus, the practical use of the steam ejector refrigerator has been the main focus of several researchers [23][24][25][26][27]. The main aim is to improve the system COP or entrainment ratio.…”

“…Ejector refrigerators have been proposed for real air conditioning applications as proposed by Thongtip et al [23], Varga et al [25], and Ruangtrakoon et al [27]. The real air-conditioning test of the steam ejector refrigerator was proposed by Ruangtrakoon and Aphornratana [27] in a hot humid climate.…”