Design and Analysis of Air-Cooled Fin and Tube Heat Exchanger with Smaller Diameter Micro Finned Tubes using R32 in Replacement of R410A

Abstract

Difluoromethane (HFC32) is the perfect replacement of R410A due to its zero ozone depletion Potential and lower Global warming potential (GWP as 675) that is much less than R410A (2088) and Zero Ozone Depletion Potential. R32 refrigerant can achieve higher heat transfer coefficients with less quantity of refrigerant charge when compared to R410A. Fin and Tube heat exchangers (FTHE) are widely used in the refrigeration, air conditioning industries and in many other applications to exchange or transfer the heat from refrigerant or working fluid and to the sink. The aim of this paper is to calculate the Heat transfer coefficient, pressure drop and heat load of refrigerants in Air-cooled Fin and Tube heat exchanger. Here FTHE is used as a condenser in one TR residential air conditioning application and their comparison using R32 and R410A refrigerants. To study the behaviour of two refrigerants in liquid phase, two phase (liquid and vapor phase) and vapor phases inside the condenser. Here the airflow to the condenser is counter flow. Materials used were Aluminium for fins and copper for tubes to achieve greater heat transfer coefficient. Here fin and tube material combination is very important because of their material properties. Optimizing the design of FTHE, i.e. selecting the micro finned tubes to generate turbulence in refrigerant flow, which results in enhancement of heat transfer coefficient. Slit type fin is selected for fins. The micro finned copper tubes with smaller inner diameter can save the material cost. Coil Designer a simulation software used for the design and analysis of FTHE.