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...

This paper describes an ejector model for the prediction of on-design performance under available conditions. is a direct method calculating optimal (entrainment ratio or ER) without need iterative methods, which have been conventionally used. The values three efficiencies used to account losses in are calculated by using systematic approach (by employing CFD analysis) rather than hit and trial...

an irreversible stirling heat pump cycle using ferromagnetic materials as a cyclic working substance is established. the influences of finite-rate heat transfer, heat leak, regeneration time, regenerative lossand the internal irreversibility on the cyclic performance of magnetic heat pumps are taken into account. on the basis of the thermodynamic properties of ferromagnetic materials, the perfo...

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...

Abstract The following work documents the effect of streamwise vortices generated at the nozzle exit of an axisymmetric air jet on the amount of mass entrained into an ejector. In an experimental analysis of the mass entrainment of circular jet ejectors, we found that the introduction of half delta wing vortex generators in the exit of the jet nozzle (Reynolds number of 50,000) increased the am...