Refrigerator is one of the home appliance utilizing mechanical vapour compression cycle in it process. Performance of the system becomes main issue and many researches are still ongoing to evaluate and improve efficiency of the system. Therefore, this paper presents the development process of refrigerator test rig and performance evaluation of a domestic refrigerator that has been used in Malay...

Compression of pure refrigerants in the two-phase flow region has a number of advantages for the performance of vapor compression systems. Compressors may be lubricated by liquid refrigerant so that the process side of the cycle is not contaminated by lubricant. The compression process can be realized in the two-phase region preventing superheating with its associated irreversibility losses. Th...

The world-wide agreement to restrict the use of chlorofluorocarbons (CFCs) and hydrofluorocarbons has prompted recent research exploring the possibilities of replacement refrigerants, particularly those occurring naturally in the environment. One such natural refrigerant, carbon dioxide, has been shown for particular applications to have a COP which is competitive with current refrigerants. How...

Title of Document: Efficiency Enhancement for Natural Gas Liquefaction with CO2 Capture and Sequestration through Cycles Innovation and Process Optimization Abdullah Alabdulkarem, Doctor of Philosophy, 2014 Directed By: Professor, Reinhard Radermacher, Mechanical Engineering Liquefied natural gas (LNG) plants are energy intensive. As a result, the power plants operating these LNG plants emit hi...

The ongoing global effort to replace current refrigerants with zero Ozone Depletion Potential (ODP) and virtually zero Global Warming Potential (GWP) refrigerants has important implications for heat exchangers, air conditioning system design, and the materials choices in these designs. Natural refrigerants with higher flammability, CO2, HFOs, and HFC – HFO blends each place different requiremen...

Due to the transcritical nature, some of the test methods used in the conventional subcritical refrigeration cycle, such as the liquid refrigerant flow metering method and the water-cooled condenser metering method, are no longer appropriate for evaluating the transcritical carbon dioxide (CO2) compressor performances. This paper introduces a performance test facility taken into account both th...

In the present work, various objective functions were formulated and optimized using mixed integer nonlinear programming generalized reduced gradient method from solver tool of Microsoft® Excel 2016, respectively. The CH3FO2, C2H4F2O, CH2F2O2, CH2F2O, C3H4F2, C2H2F2O molecules found to meet structural feasibility constraints physical properties refrigerant have not previously been reported in l...