A suction line of a refrigeration cycle with vertical upward flow is one area where the refrigeration oil tends to accumulate. This paper discusses the flow characteristics of the oil film in a pipe with the vertical upward flow. Air and oil two-phase flow is used as the first step of the study and the flow pattern of the oil film in the vertical upward flow is observed. The oil film thickness ...

The effect of the internal heat exchanger (IHE) on the performance of the transcritical carbon dioxide refrigeration cycle with an expander is analyzed theoretically on the basis of the first and second laws of thermodynamics. The possible parameters affecting system efficiency such as heat rejection pressure, gas cooler outlet temperature, evaporating temperature, expander isentropic efficienc...

The purpose of this paper is multi-objective optimization of refrigeration cycle by optimization of all components of the cycle contains heat exchangers, air condenser, evaporator and super-heater. Studied refrigeration cycle is compression refrigeration cycle of unit 132 Third refineries in south pars that provide chilled water for cooling refinery equipment's. Cycle will be performed by t...

Refrigeration is one of the leading uses of electric power in the United States. The term "refrigeration" refers to air-conditioning for homes, businesses, and industry and the operation of refrigerators, freezers, and heat pumps. The technology most often used in refrigeration, the vapor compression cycle, is 100 years old, inefficient, and environmentally unsound. Since the 1980s, the refrige...

Refrigeration is one of the leading uses of electric power in the United States. The term "refrigeration" refers to air-conditioning for homes, businesses, and industry and the operation of refrigerators, freezers, and heat pumps. The technology most often used in refrigeration, the vapor compression cycle, is 100 years old, inefficient, and environmentally unsound. Since the 1980s, the refrige...

In this study, a cascade refrigeration system comprising gas and vapor compression cycles operating at ultra-low temperature was designed. the thermodynamic analyses, R744, R404A, R410A refrigerants in high cycle (HTC), R1150, R170, R23 low (LTC) were used. Thermodynamic analyses carried out using Engineering Equation Solver package program. Outputs considered were: performance(COP), ratio, mas...

This paper presents recent developments and state of the art for transcritical CO2 cycle technology in various refrigeration, air-conditioning and heat pump applications. The focus will be on fundamental process and system design issues, including discussions of properties and characteristics of CO2, cycle fundamentals, methods of high-side pressure control, thermodynamic losses, cycle modifica...

In this study thermodynamic performance analysis of a combined organic Rankine cycle and ejector refrigeration cycle is carried out for use of low-grade heat source in the form of sensible energy. Special attention is paid to the effects of system parameters including the turbine inlet temperature and turbine inlet pressure on the characteristics of the system such as ratios of mass flow rate, ...

The paper focuses on operation of simple refrigeration cycles and considers the selection of controlled variables for two different cycles. One is conventional sub-critical ammonia refrigeration cycle and the other is a trans-critical CO refrigeration cycle. There is no fundamental difference 2 etween the two cycles in terms of degrees of freedom and operation. However, in practical operation t...