Authors: V.N. Raibhole; D.A. Kamble
Addresses: Modern Education Society's College of Engineering, 19, Late Prin. V. K. Joag Path, Bund Garden, Pune, Maharashtra, India ' Vishwakarma Institute of Information Technology, Kohbhwa (Bk), Pune, Maharashtra, India
Abstract: Many industrial applications need low-temperature cooling which single-stage refrigeration systems are unable to produce efficiently due to specific limitations of refrigerants used. Therefore, a cascade refrigeration system is one of the paramount substitutes in such applications. This paper presents a simulation of a cascade refrigeration system with hydrocarbon refrigerant, R290 in a low-temperature circuit (LTC) and natural refrigerant, ammonia in a high-temperature circuit (HTC). Both the refrigerants in this refrigeration system have low GWP and zero ODP, hence, eco-friendly with the environment. The main thrust of this study is to determine various performance parameters of the cascade refrigeration system and carry out exergy analysis as well as parametric analysis of the system. In this simulation the cascade refrigeration system achieves low temperature as -30°C in low temperature evaporator and cooling capacity 15 kW with COP of 6.024. It is observed that the work of compressors in LTC and HTC are 2.49 kW and 11.21 kW respectively, whereas total work of the cascade system is 13.7 kW at these operating conditions. It is considered to utilise refrigerant gas discharge superheat for heating of water to enhance overall performance of the system. The parametric analysis of cascade refrigeration system involves parameters like evaporator temperature, condenser temperature, degree of superheat, sub-cooling after condenser and utilisation of degree of gas discharge superheat for heating of water to determine effect on the system performance.
Keywords: ammonia; cascade refrigeration system; COP; exergy analysis; parametric analysis and R290; low temperature circuit; LTC; high temperature circuit; HTC.
International Journal of Environmental Engineering, 2022 Vol.11 No.4, pp.261 - 276
Received: 17 Jul 2020
Accepted: 12 Jul 2021
Published online: 04 Jan 2023 *