in this paper, we are going to improve the energy efficiency of an industrial c 3 mr base load lng plant by changing its refrigerant components and its mole fractions in liquefaction and subcooling cycles based on the cooling curves generated in the main liquefaction and subcooling heat exchangers. later on, selection features of the elements will be discussed. first, non-optimized c 3 mr plant...

a modification of peng-robinson equation is described wherein in the parameter b is expressed as a linear function of temperature. the modified equation is then applied to a series of light hydrocarbons and refrigerants, and predicted values for vapor pressure, saturated vapor volume, saturated liquid volume and the heat of evaporation are compared with the corresponding experimental data. cons...

The impact of refrigeration systems on the environment can be reduced by: a) the use of alternative refrigerants which are less harmful to the environment and b) the optimisation of systems and control strategies to deliver increased levels of energy efficiency_ Mathematical modelling offers the opportunity to test the performance of systems under different operating conditions and with alterna...

Practical and empirical equations of transport properties have been developed for refrigerant compounds. These equations have been used to develop correlations for experimental heat transfer coefficient (IITC) for both evaporation and condensation in smooth tubes. Model calculations have been compared with recent experimental data, and reasonable agreement has been obtained. INTRODUCTION We hav...

High-temperature heat pumps (HTHPs) are compression systems that convert residual to high-grade used in several industrial applications. Refrigerants for HTHPs still not explored, and most studies consider only pure refrigerants. This study carries out a general screening of binary ternary mixtures through multiparameter optimization based on low global warming potential (GWP) refrigerants feas...

The decline in religious identification and corresponding increase in the unaffiliated has been one of the most important religious changes in the United Kingdom (UK). The emergence of the “religious nones” is the most obvious sign of continuing secularization and the declining social and cultural relevance of religion. Yet while the religiously-unaffiliated often form the plurality — if not so...

The transition from CFC-12 (GWP=10,900) to HFC-134a (GWP=1,430) in the 1990’s in new vehicle air conditioners eliminated the contribution to ozone depletion potential (ODP) from new vehicles and reduced the direct Global Warming Potential (GWP) by over 80%. One proposed alternative is HFC-1234yf (GWP=4). Despite the phase-in success of HFC-134a as a zero ODP automotive refrigerant it is still a...

Analysis of compression mechanisms requires a prediction of the pressure during the compression and expansion processes. A common model is the polytropic process, PV = constant. This paper presents a method for determining the best polytropic exponent to use and suggests values for some common refrigerants used in the air conditioning and refrigeration industry. INTRODUCTION When a gas undergoe...

Due to the desirable and interesting applications of refrigerants in organic Rankine cycles, heat pumps, refrigeration, engineers researchers are becoming more interested refrigerant properties. One most dominant thermophysical properties these fluids is their normal boiling point (Tb). In current study, a novel extreme learning method (ELM) ensemble decision tree boosted algorithm (EDT Boosted...

Abstract Environmental concerns have created need to find replacements for HFC and in some cases HCFC refrigerants used screw compressor applications. Like most refrigerant changes it becomes necessary assess the best lubricant option order maintain system reliability performance. Regardless of magnitude allows opportunity appraise alternative chemistries that are different from what was past. ...