Performance Analysis of Alternative Refrigents Inside Capillary Tube of Refrigeration System

International Journal of Mechanical Engineering

© 2017 by SSRG - IJME Journal

Volume 4 Issue 12

Year of Publication : 2017

Authors : B.N.C. Mohan Reddy, J.A.Sandeepkumar, A.V. Hari Babu

10.14445/23488360/IJME-V4I12P103

How to Cite?

B.N.C. Mohan Reddy, J.A.Sandeepkumar, A.V. Hari Babu, "Performance Analysis of Alternative Refrigents Inside Capillary Tube of Refrigeration System," SSRG International Journal of Mechanical Engineering, vol. 4,  no. 12, pp. 8-23, 2017. Crossref, https://doi.org/10.14445/23488360/IJME-V4I12P103

Abstract:

The chlorofluorocarbon (CFCs) and hydro-chlorofluorocarbon (HCFCs) refrigerants are being replaced by hydro-fluorocarbons (HFCs) due to environmental concerns about depletion of the earth’s protective stratospheric ozone layer and global climate change. A refrigeration system using new alternative refrigerants must be modified or newly designed because the thermo-physical properties of these alternative refrigerants differ from those of conventional refrigerants. In order to maintain or improve the performance of the cycle, the operating characteristics of individual components of the system should be clarified for use with the new alternative refrigerants. . In this work, a full array of methane and ethane derivatives were considered and the trade-off in flammability, toxicity and chemical stability concerning atmospheric lifetime with changes in molecular chlorine, fluorine and hydrogen content were carried out. Therefore, two single-fluid alternative refrigerants (R410a and R134a) that contain no chlorine were selected for the investigation along with R22.In the present investigation, the performance of alternative refrigerants in an adiabatic capillary tube was investigated using ANSYS CFX in a vapour compression refrigeration system. The proposed model predicts the flow characteristics in adiabatic capillary tube for a given mass flow rate. In the present study alternative refrigerants R-22, R-134a and R-410a are used as working fluids inside a straight capillary tube of diameter 1.27mm and used the same model to study the flow characteristics of refrigerants. The mass flow rate is compared for these refrigerants and best suited refrigerant is suggested. The mass flow rates of R-134a and R410a were 34.828% higher and 2.22% lower than that of R-22 respectively. As a result R-410a is a good substitute for R-22 but only the compressor size should be increased as the pressures are 50% higher than that of R-22.

Keywords:

Refrigerants- R22- R-134a - R410-AANSYS CFX–massflow rates- shapes

References:

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