Title: Experimental performance of an automobile air conditioning system using a variable capacity compressor for two different types of expansion devices
Authors: Alpaslan Alkan, Murat Hosoz
Addresses: Department of Mechanical Education, Kocaeli University, Umuttepe, Kocaeli, 41380, Turkey. ' Department of Mechanical Education, Kocaeli University, Umuttepe, Kocaeli, 41380, Turkey
Abstract: An experimental R134a automotive air conditioning (AAC) system with a variable capacity compressor has been developed and equipped with various mechanical instruments. The system has the capability of using both a thermostatic expansion valve (TXV) and an orifice tube (OT) as an expansion device. The system has been tested by varying the compressor speed and temperatures of the air streams entering the condenser (Tcond,ai) and evaporator (Tevap,ai). Using experimental data, the performance parameters of the AAC system for TXV and OT operations have been evaluated. The results show that the cooling capacity usually increases with the compressor speed. However, the exergy destruction in the system also increases and the coefficient of performance (COP) decreases with the compressor speed. The cooling capacity and COP decrease on rising Tcond,ai, while they increase on rising Tevap,ai. The TXV operation usually yields slightly higher cooling capacity and COP and lower exergy destruction compared with OT operation.
Keywords: automobile industry; automotive air conditioning; refrigeration; thermostatic expansion valve; TXV; orifice tube; R134a; vehicle air conditioning; variable capacity compressors; compressor speed; air stream temperatures; exergy destruction; coefficient of performance; cooling capacity.
International Journal of Vehicle Design, 2010 Vol.52 No.1/2/3/4, pp.160 - 176
Published online: 30 Nov 2009 *Full-text access for editors Access for subscribers Purchase this article Comment on this article