This paper presents irreversibility analysis using experimental data from vapor compression chiller system R22, R407C, R404A and R-134A as working fluids. The operated under cycling condition, which allowing the water to circulate in evaporator recording every ten minutes. Further, study was conducted at different ambient temperature identify parameter that cause energy deterioration. findings ...

A soft~are packcage for both the thermodynamic properties computa-~ic~and tne analysis of usual vapor compression plant schemes is anusefu: tool for air conditioning and refrigeration researchers and mani-facture>s. At ~hePresent time, it could sUPPlY an important contribu-tion to search for CFCs substitutes; in fact, comparisons between two ormore ~o•king fluids...

Refrigerant mass migration and redistribution are regarded as key factors affecting the cycling perfor­ mance of air conditioning and refrigeration systems. A dynamic model of an R134a automotive air conditioning system is presented as an example in this paper to capture the refrigerant migration during compressor shut-down and start-up operations. Model validation against experimental data dem...

CFCs, HCFCs are stipulated to phase out, and other alternative refrigerants like R134a, are also constrained as a result from their high GWP values. CO2 as a natural working fluid now is used in reciprocating compressors due to its uniquely beneficial properties (ozone depletion potential, ODP=0; global warming potential, GWP =1). However, one remarkable characteristics of the CO2 reciprocating...

This paper describes the experimental comparison of performance of prototype transcritical C02 system for mobile ale to it's Rl34a counterpart, unit for Ford Escort that was chosen as a representative for the US, European, and Japanese markets. The paper presents the design of experiments and facilities for such comparisons and preliminary results. INTRODUCTION One objective of this project is ...

R134a sprays have been widely used as a method to protect the epidermis during laser therapies of hyper-vascular lesions, such as port wine stains, due to their high heat flux and precise control of cooling duration. Recent studies have shown that the use of vacuum cups during laser treatment can physically dilate the vasculature of interest and improve therapeutic outcome. However, the effects...

The performance of an externally pressurized gas journal bearing lubricated with R134a vapor used in oil-free refrigeration centrifugal compressor is calculated by solving Reynold equations the finite difference method (CFD). load capacity, stiffness and mass flow rate refrigerant under conditions various operational parameters are obtained compared that air bearings. In addition, influences av...