In the present work, the integral equations method is used to calculate transport properties of polar fluids. For this goal, we use the Stockmayer potential and examine theoretically the thermal conductivity of several refrigerant mixtures such as R125+R134a, R125+R32, R125+R152a, R134a+R32, R152a+R32, R134a+R143a, and R125+R143a. We solve numerically the Ornstein-Zernike (OZ) equation usin...

Measurements on R600a refrigerators have shown electricity savings over R134a and R12 up to 20%. We propose new parameters which are functions of well known refrigerant properties. These parameters show that R600a has half the leakage, pressure loss and condenser pressure and double the heat transfer coefficient of R12 and R134a explaining the measurements. Use of R600a in small heat pumps and ...

A performance analysis on a vapour compression refrigeration system with various eco-friendly refrigerants of HFC152a, HFC32, HC290, HC1270, HC600a and RE170 were done and their results were compared with R134a as possible alternative replacement. The results showed that the alternative refrigerants investigated in the analysis RE170, R152a and R600a have a slightly higher performance coefficie...

in the present work, the integral equations method is used to calculate transport properties of polar fluids. for this goal, we use the stockmayer potential and examine theoretically the thermal conductivity of several refrigerant mixtures such as r125+r134a, r125+r32, r125+r152a, r134a+r32, r152a+r32, r134a+r143a, and r125+r143a. we solve numerically the ornstein-zernike (oz) equation using th...

Series production of R134a compressors started in 1990. 200 compressors, from the very first series, were built into cabinets placed in an apartment house in Denmark. Cabinets with R12 compressors were placed in the same apartment house as well. The cabinets have two separate cooling systems; one for a cold cabinet and one for a freezer. 10 running cabinets were called back for analysis; 7 cabi...

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...

In the present paper the pressure drop characteristics of a 1.4 mm hydraulic diameter multiport minichannel tube during adiabatic two-phase flow of HFC refrigerants are discussed. The tube consists of eleven parallel rectangular cross section channels. Although much experimental research has been devoted to investigate the pressure drop characteristics of R134a inside multiport minichannels in ...

0308-8146/$ see front matter 2010 Elsevier Ltd. A doi:10.1016/j.foodchem.2010.08.042 ⇑ Corresponding author. Tel.: +60 7 5535609; fax: + E-mail address: [email protected] (Z.A. Manan) Sub-critical extraction of palm oil from palm mesocarp using R134a solvent was conducted via the dynamic mode to investigate the ability of R134a to extract b-carotene. The yield of palm oil and the solubility of...

The present paper is a numerical and experimental comparative study of hermetic and semi-hermetic reciprocating compressors working with carbon dioxide as fluid refrigerant against the conventional R134a hermetic compressors. When cooling conditions for one-stage compressor type (i.e., evaporation temperatures between 7.2oC and –10oC) have been considered, the numerical and experimental results...