New experimental data on the thermal conductivity of 2,3,3,3-tetrafluoroprop-1-ene (R1234yf) and trans-1,3,3, 3-tetrafluoropropene (R1234ze(E)) are reported that allow the development of wide-range correlations. These new experimental data, covering a temperature range of (242 to 344) K for R1234yf and (203 to 344) K for R1234ze(E) at a pressure range of (0.1 to 23) MPa, are used to develop cor...

In this paper the techno-economic feasibility of employing zeotropic mixtures as working fluids in organic Rankine cycle power systems is assessed. For an application case based on utilization low temperature geothermal heat at 135 °C, net present value system was maximized by optimizing process variables and transfer equipment design parameters. Parametric studies detailing effect assumed elec...

In this study, three new mixed refrigerants with low GWP values, R1234yf/R134a, R1234yf/R125, and R1234yf/R13I1, were evaluated as replacements for R134a refrigerant using two vapor compression configurations. The experiment revealed that these mixtures can be used environmentally friendly alternatives configuration.

The viscosities of dimethyl ether (DME, C2H6O) and of the fluorinated propene isomers 2,3,3,3-tetrafluoroprop-1-ene (R1234yf, C3H2F4) and trans-1,3,3,3-tetrafluoropropene (R1234ze(E)) were measured in a combined temperature range from 242 K to 350 K at saturated liquid conditions. The instrument was a sealed gravitational capillary viscometer developed at NIST for volatile liquids. Calibration ...

air conditioning refrigerant r134a has value of global warming potential (gwp) 1300, which is much higher than mac directive (gwp below 150) passed in july 2006. this prompted a search for alternative refrigerant with gwp value less than 150. r1234yf is a new refrigerant which has lower gwp value of 4. effect of blower speed has been compared and flammability issue of r1234yf has been addressed...

Air conditioning refrigerant R134a has value of global warming potential (GWP) 1300, which is much higher than MAC Directive (GWP below 150) passed in July 2006. This prompted a search for alternative refrigerant with GWP value less than 150. R1234yf is a new refrigerant which has lower GWP value of 4. Effect of blower speed has been compared and flammability issue of R1234yf has been addre...

The thermophysical properties of a refrigerant can be modified via adding metal organic frameworks (MOF) to it. Understanding the adsorption–diffusion process mixture in MOFs at molecular level is important further improve efficiency Rankine cycle. adsorption and diffusion R32/R1234yf MOF-200 was investigated by dynamics simulation present work. results show that number adsorbed molecules R32 p...

The condensation heat transfer characteristics of nonazeotropic mixtures R1234yf and R32 (mass fractions of 0.52:0.48 and 0.77:0.23, respectively) inside a horizontal smooth tube (inner diameter 4 mm) were experimentally studied at mass fluxes ranging from 100 to 300 kg/m s. A prediction model for the forced convective condensation heat transfer characteristics of nonazeotropic refrigerant mixt...

The simulation configuration and process analysis of the Subcritical Organic Rankine Cycle (SORC) system are carried out for potential comparison between pure, binary, ternary zeotropic mixtures R1234ze(E), R1234yf, R134a as refrigerant working fluids based on applying flue gas a heat source with medium temperature. compression pressure was selected an optimized variable input parameter SORC lo...

The use of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) has been widely restricted. They have been replaced with hydrofluorocarbons (HFCs) in order to protect the ozone layer. However, the leakage of refrigerant into air from active or end-of-life air conditioners has been a serious environmental issue owing to the high global warming potential (GWP) of HFCs. It has therefore...