In this paper a mathematical model for the working process of a refriceration helical screw compressor is presented and discussed. The manner in which geometric parameters such as cell volume, sealing line length, blow hole are..,, discharge port area etc. a.re related to rotation angle is established a.nd used in the thermodynamic model which is based on real cas laws. The influence of factors...

The refrigeration industry has been in a state of flux primarily because of the phase-out of ozone-depleting CFC refrigerants, and secondarily because of recent advances in compressor technology. This paper contains a review of current substitutes for CFCs and HCFCs which are under consideration by the compression refrigeration industry, an assessment of their characteristics related to choice ...

Water as a refrigerant (R718) is compared with other modern refrigerants (R717, R290 R134a, R12, R22, and R152a) regarding refrigeration capacity and COP (coefficient of performance). A computer program simulating a theoretical vapor compression refrigeration cycle was developed to calculate COPs, compression ratios, and discharge temperatures of the refrigerants from the compressor. The effect...

Nanoparticles have recently attracted huge attention as an engineering alternative in various fields. This is not unconnected with its established ability to perform better when used replace some conventional systems or enhancement for the system. Hence, this study reviewed viability of nanofluids developed from nanoparticles a possible replacement refrigerants available. In review, focus was p...

Martensitic hardening is a technology widely used in mechanical engineering practice to increase the hardness and abrasion resistance of ferrous alloys. To achieve martensitic hardening, workpiece must be cooled very quickly, which can achieved through using various refrigerants. The quality properties these coolants have great influence on success process, so their investigation essential. Thr...

This study includes energy and exergy analysis if air ground source 
 heat pumps are used for residential heating in Kastamonu province. The lowest soil temperatures measured between December March 2000-2021 were taken into account. R134a, R407c, R410a R500 as refrigerants the process that will benefit from heating. In discussed, ambient temperature to be heated was chosen same each pump, ...

Global warming is one of the most pressing issues world facing today. The refrigeration sector, major contributors to global warming, needs follow a methodological approach address this issue. This paper evaluates overall impact along with thermodynamic performance different generations refrigerants in cascade system. main aim comparative study present comprehensive outlook on environmental ref...

• R516A, R513A, and R1234yf are compared as alternatives to R134a. The first experimental results of the R516A blend presented. R513A presents highest overall system performance by enhancement 2% in cooling mode. In mode, shows COP at low evaporating temperatures ranging from (1 15%). This work an comparison for GWP refrigerants used vapour compression heating systems. study compares three lowe...