Vapour compression refrigeration is the most widely used method in domestic and commercial air conditioning and refrigeration systems. R22 (difluoromonochloromethane) is the most widely used HCFC (hydro chlorofluorocarbon) refrigerant in residential, commercial, industrial and transport cooling systems. Montreal protocol in 1987 banned the use of CFCs (chlorofluorocarbon) due to their adverse impact on the environment causing ozone depletion and global warming. HCFCs are also being phased out, though they are less destructive than CFCs. The present work explores compressor performance using alternate environment friendly working fluids so that R22 can be replaced in future. The refrigerants used for the studies are R134a (tetrafluoroethane), R290 (propane) and R600a (isobutane). Compressor performance is analysed by varying refrigerant mass flow rate, evaporator and condenser temperatures and studying their effect on compressor size, power and discharge temperature. A numerical simulation code has been developed in MATLAB using refrigerant properties taken from REFPROP.
Increase in the consumption of electrical energy worldwide has laid the emphasis on replacing electrical energy with thermal energy wherever possible. In this paper, the bubble pump, which is ‘heart’ of diffusion- absorption refrigeration system, has been investigated numerically. A thermally driven bubble pump, which can be powered by waste heat or solar thermal energy, is used to lift the liquid. As a result of the absence of any mechanical moving part, the refrigerator is silent and very reliable in addition to aneconomicalandenvironmental friendlydevice. The concept of such a pump is already in existence but optimization studies are yet to be extensively investigated. This paper deals with the optimization of various parameters of the bubble pump usingwateras the working fluid. Parametric studies are carried out and a design optimization for maximum efficiency is performed for various operating conditions.Numerical simulation of the bubble pump is carried out using simple numerical equations which assume slug flow in the bubble pump. The diameter of the pipe and the position of the heating element are varied and the effect it has on time taken, pumping ratio and pumping ratio for one pumping cycle is studied.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.