Performance Evaluation of a Window Room Air Conditioner With Micro-Channel Condensers

Mapping Intimacies ◽

10.1115/imece2000-1304 ◽

2000 ◽

Author(s):

Man-Hoe Kim ◽

Clark W. Bullard

Keyword(s):

Performance Evaluation ◽

Heat Exchangers ◽

Micro Channel ◽

Performance Tests ◽

Air Conditioner ◽

Air Conditioning System ◽

Baseline System ◽

Inlet Conditions ◽

Core Volume ◽

System Characteristics

Abstract The performance evaluation for a residential window air conditioning system with micro-channel condensers has been performed. First, a series of wind-tunnel calorimeter tests are conducted for two different prototype micro-channel heat exchangers. The measured heat transfer and pressure drop characteristics for the heat exchangers are then compared to four conventional finned round tube designs, which were obtained using a validated simulation model for identical air and refrigerant inlet conditions. Finally, two prototype micro-channel condensers are installed in the system and system performance tests are conducted. System characteristics such as capacity, energy efficiency ratio, and suction and discharge pressures and temperatures are presented, compared to those for the conventional system. Refrigerant charge amount for a window air conditioner with a micro-channel condenser is decreased by 35%, and the condenser core volume and weight can be reduced by 55% and 35%, respectively, compared to the conventional baseline system.

Download Full-text

Performance Evaluation of a Window Room Air Conditioner With Microchannel Condensers

Journal of Energy Resources Technology ◽

10.1115/1.1446072 ◽

2002 ◽

Vol 124 (1) ◽

pp. 47-55 ◽

Cited By ~ 23

Author(s):

Man-Hoe Kim ◽

Clark W. Bullard,

Keyword(s):

Performance Evaluation ◽

Heat Exchangers ◽

Performance Tests ◽

Air Conditioner ◽

Efficiency Ratio ◽

Air Conditioning System ◽

Baseline System ◽

Inlet Conditions ◽

Core Volume ◽

System Characteristics

A performance evaluation for a residential window air conditioning system with microchannel condensers has been performed. First, a series of wind-tunnel calorimeter tests were conducted for two different prototype microchannel heat exchangers. The measured heat transfer and pressure drop characteristics for the heat exchangers were then compared to calculated value for four conventional finned round-tube designs, which were obtained using a validated simulation model for identical air and refrigerant inlet conditions. Finally, two prototype microchannel condensers are installed in the system and system performance tests were conducted. System characteristics such as capacity, energy efficiency ratio, and suction and discharge pressures and temperatures are presented, and compared with those for the conventional system. Refrigerant charge requirements for a window air conditioner with a microchannel condenser can be decreased by 35 percent compared to the conventional baseline system. The condenser core volume and weight can be reduced by 55 and 35 percent, respectively.

Download Full-text

Numerical Simulation of Operating Performance of Heat Exchangers in a Residential Split Air-Conditioner

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.3913 ◽

2011 ◽

Vol 250-253 ◽

pp. 3913-3918 ◽

Cited By ~ 2

Author(s):

Shun Yu Su ◽

Tian Tian ◽

Jian Chen

Keyword(s):

Heat Transfer ◽

Fluid Flow ◽

Heat Exchangers ◽

Great Influence ◽

Working Fluid ◽

Air Conditioner ◽

Two Phase ◽

Air Conditioning System ◽

Flow And Heat Transfer ◽

Phase Fluid

The mechanism of fluid flow and heat transfer in the heat exchangers was investigated in this paper. Using R22 as the working fluid, the steady distributed parameter models of condenser and evaporator in a residential split air-conditioner were established based on thermophysical laws such as mass, momentum and energy conservation equations. The regions of two-phase fluid and superheated gas in evaporator and the regions of superheated gas, two-phase fluid and subcooled liquid in condenser were respectively simulated under designed conditions of air-conditioning system. Based on the calculated results, the flow and heat transfer performances of heat exchangers were analyzed. The results show that the two-phase fluid regions in both evaporator and condenser have great influence on the fluid flow and heat transfer performances in it.

Download Full-text

Development of a Micro-Channel Evaporator Model for a CO2 Mobile Air-Conditioner

10.1115/imece2000-1295 ◽

2000 ◽

Author(s):

M.-H. Kim ◽

J. M. Yin ◽

C. W. Bullard ◽

P. S. Hrnjak

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Pressure Drop ◽

Mass Transfer Process ◽

Micro Channel ◽

Air Conditioner ◽

Air Conditioning System ◽

Side Pressure ◽

Volume Method ◽

Energy Balances

Abstract This paper presents the development and verification of a heat exchanger model for evaluating thermal performance of an evaporator for a CO2 mobile air-conditioning system. The model has been developed, based on the finite volume method, with emphasis on the air-side heat and mass transfer process. The governing equations are derived from mass and energy balances using newly developed air-side heat transfer and friction loss correlations for micro-channel heat exchangers under dry and wet conditions. The calculated air-side heat transfer and pressure drop data are in good agreement with measured data. However, the refrigerant-side pressure drop estimation for micro-channel tubes usually underestimates the measured value. The simulation results and importance of selecting appropriate heat transfer and pressure drop correlations for the micro-channel heat exchanger are addressed.

Download Full-text