Experimental performance analysis of a packaged R290 refrigeration unit retrofitted with R170 for ultra-low temperature freezing

Two-stage cascade configurations based on ejectors for ultra-low temperature refrigeration with natural refrigerants

“…This proposal analysed the behaviour of commercial compressors using information available in their software. This model is also valid for R-170 [30] …”

“…Regarding new working fluids for two-stage ULT cascade refrigeration cycles, Rodriguez-Criado et al [13] retrofitted a standard low-temperature R-290 packaged unit to use R-170. For a cold room temperature of −80°C and −65°C, the COP ranged from 0.6 to 1.6.…”

Finding the proper position of supply and return registers of air condition system in a conference hall in term of COVID-19 virus spread

“…On the other hand, humans spend 85% of their time in closed environments such as homes, workplaces, offices, cinemas, conference halls, transportation vehicles, etc. [2] . The combination of these issues has caused the issue of indoor air quality to be considered by architects and building HVACʼs specialists in recent years.…”

Advanced two-stage cascade configurations for energy-efficient –80 °C refrigeration

“…Regarding lower evaporating temperatures, Adebayo et al, [31] concluded that R-717/R-744 results in the highest COP at –50 °C evaporation temperature, while the lowest is HFE-7100/R-744, being R-134a and HFE-7000 in an intermediate position. Rodríguez-Criado et al, [32] adapted a standard low-temperature R-290 packaged unit with R-170 between –80 °C and –65 °C evaporating temperature, and they measured COP between 0.6 and 1.6.…”