Simulation and performance evaluation of air-cooled finned-tube gas cooler for trans-critical carbon dioxide refrigeration system in Indian context

Abstract

This paper presents, the mathematical modeling, validation and simulation of air-cooled finned tube gas cooler for trans-critical carbon dioxide (CO2) refrigeration system in typical Indian conditions. Environmental concerns and enactments of Montreal and Kyoto Protocol for sustainable growth enforce research for ecologically safe and natural refrigerants and cost effective designs of refrigeration systems. CO2 is one of the rediscovered sustainable options, as CFCs and HFCs are now in the list of regulated substances and are gradually to be phased out. Success of CO2 as a refrigerant, demand cost effective and widely acceptable technology operable at various environmental conditions. In this work, performance of gas cooler for trans-critical CO2 refrigeration system is analyzed. The conservation equations are discritized using finite difference scheme and code is developed in MATLAB® to solve these equations. Consequently simulated results are validated by using published data. The validated model is used to analyze the performance of possible alternative designs of gas cooler with an aim to enhance heat transfer or reduce approach temperature for typical Indian climatic conditions. The coefficient of performance of the system is also studied with possible design of gas cooler in Indian climatic condition. This work can help in formulating design guideline for a trans-critical CO2 refrigeration systems that need to be tuned to local environment condition for performance enhancement.