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    Analytical computation of gwp, odp, rf number and tewi analysis of various r134a/r1270/r290 blends as r22 alternatives
    (CRC Press/Balkema, 2018) Vali, S.S.; Ashok Babu, T.P.
    The principal objective of the present work is to compute the GWP, ODP, RF number and TEWI analysis of various ternary R134a/R1270/R290 blends as alternatives to R22. In this study thirteen refrigerant blends consists of R134a, R1270 and R290 at different compositions are taken. GWP and ODP of refrigerant blends are computed by using various simple correlations. The estimation of emission of greenhouse gases and flammability study of refrigerants are done by using TEWI and RF analysis respectively. Analytical results revealed that all the thirteen studied fluids are ozone friendly in nature. The GWP of refrigerant M6 (651) is lower than that of GWP of R22 (1760). RF analysis exhibited that all the thirteen refrigerant blends are categorized as ASHRAE A2 flammability category. Thermodynamic analysis revealed that COP of M6 (3.608) is higher that of COP of R22 (3.534). TEWI of M6 is lower among the R22 and thirteen studied fluids. Hence refrigerant M6 (R134a/R1270/R290 50/5/45 by mass%) is an alternative to R22. © 2018 Taylor & Francis Group, London.
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    Theoretical thermodynamic performance assessment of various environment-friendly novel refrigerants used in refrigeration systems
    (SAGE Publications Ltd info@sagepub.co.uk, 2020) Vali, S.S.; Ashok Babu, T.P.A.
    The present investigation focuses on theoretical performance of various new environment-friendly refrigerant mixtures as substitutes to high global warming potential refrigerant R22. In this investigation, 34 refrigerants were considered at various composition. In this work, both complex vapor compression cycle (actual cycle) and standard vapor compression cycle (ideal cycle) was considered for the performance assessment of refrigerants. Vital studies such as flammability, toxicity, and environmental impact of various novel refrigerants were also carried out in this study. Results obtained from actual cycle showed that the coefficient of performance of refrigerant mixture RM40 (R1270/R134a 90/10 in mass %) (2.728) was the greatest among 34 investigated alternatives and it was closer to the coefficient of performance of R22 (2.770). Compressor discharge temperature of RM40 was 13.36 ? lower when compared with R22. Volumetric refrigeration capacity of RM40 (3335 kJ/m3) was slightly higher than that of R22 (3297 kJ/m3). Power spent per ton of refrigeration of RM40 (1.288 kW/TR) was marginally higher than that of R22 (1.269 kW/TR). Global warming potential (GWP100) of RM40 (133) was very low compared to the GWP100 of R22 (1760). Total equivalent warming index (environmental impact) of RM40 was 5.61% lower than R22. However, performance results obtained from standard cycle for various investigated refrigerants were better than actual cycle, since various losses occur were neglected in the standard cycle. Overall, thermodynamic performance of refrigerant mixture RM40 (R1270/R134a 90/10 in mass %) obtained from both actual and standard cycle was the highest among 34 investigated refrigerants and it was very closer to the performance of R22 and hence, it could be considered as an environment-friendly alternative to replace high GWP refrigerant R22 used in refrigeration systems. © IMechE 2019.