The primary goal of work described in this paper is to evaluate and enhance a virtual refrigerant charge sensor, developed in a previous study. The virtual refrigerant charge sensor algorithm employs low-cost and non-invasive measurements (i.e. surface mounted temperature measurements) to estimate refrigerant charge level for packaged air conditioning systems. It can be embedded within a portab...

ORC technology is one of the most promising technologies for use residual energy in generation electrical energy, offering simple and environmentally friendly alternatives. In this field, selection working fluids plays an important role operation cycle, whether terms efficiency or minimization environmental impacts. Therefore, paper, a comprehensive review presented on R1234yf refrigerant its m...

Oil return from the evaporator to the compressor suction port is an important requirement. It is affected by the refrigerant/lubricant properties, gas velocities and piping geometry. The refrigerant R -134a has successfully replaced R-12 in household refrigerators and freezers. This paper describes a test method to estimate the mean oil film thickness and to observe the flow pattern in vertical...

This paper presents how the refrigerant dissolved in oil affects on Journal bearings reliability. The bearing model test is performed using the hermetic test apparatus. The oil film pressure is measured under several types of bearing grooves, L/D ratios and mixing ratios of refrigerant to oil. As a result, the means by which the refrigerant dissolved in oil causes damage to journal bearings is ...

In this work, new thermodynamic models for refrigerant mixtures are provided the binary pairs R-1234yf/134a, R-1234yf/1234ze(E), and R-134a/1234ze(E) based on reference measurements of speed sound, density, bubble-point pressures. Fitting very accurate liquid-phase sound density data reproduces pressures to within close their uncertainty, yielding deviations in less than 0.1% 1% (and R-1234yf/1...

f liquid g gas ABSTRACT The experimental apparatus was build according to the national standards of India.. The performance of the refrigeration system depends upon the heat transfer capacity of the refrigerant. Normally R12, R22, R600, R600a and 134a are used as a refrigerant. This refrigerant heat transfer capacity is not so good and increase power consumption. Due to these limitation nanoflu...

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...

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...