A vapor jet refrigeration system (VJRS) is an alternative to the conventional mechanically driven vapor-compression refrigeration system. The VJRS utilizes supersonic ejector as thermal compressor and has the potential to reduce energy consumption and utilize low grade energy for driving the refrigeration systems. In the present study, the performance characteristics of VJRS ejectors with R134a...

------------------------------------------------------------------------------------------------------------------------------------------------------This study was carried out to assess the proximate composition of Tilapia (Oreochromis niloticus) and Mackerel (Scomber scombrus) treated with varying concentration (1%, 3% and5%) of sodium metabisulphite, sodium benzoate and potassium sorbate dur...

Low-temperature energy systems are processes that require cooling at temperatures below ambient, which are accomplished using refrigeration cycles. Little research has addressed the operational optimisation of refrigeration cycles considering the performance of existing equipment. This work develops a methodology for operational optimisation of refrigerated processes, taking into account existi...

Compared with traditional gas-compression/expansion refrigeration, magnetic refrigeration based on magnetocaloric effect (MCE) exhibits the advantages of high energy efficiency and environment friendliness. Here, we created large MCE in RFeO3 (R = Tb or Tm) single crystals by the magnetization vector rotation of single crystal with strong magnetocrystalline anisotropy (MCA), rather than merely ...

The effect of combinations of sage, oregano and honey on lipid oxidation in cooked chicken meat during refrigeration at 4°C for 96h was determined. Chicken samples (thigh and breast) were then separated into five groups: control; butylated hydroxytoluene; oregano+sage; oregano+sage+5%honey and oregano+sage+10%honey. Quantitative measurements of thiobarbituric acid reactive substances, conjugate...

A dynamic model of a single-effect absorption refrigeration cycle has been developed. Modeling of the cycle performance requires thermodynamic properties which are obtained from equations of state for refrigerant-absorbent mixtures. The transient response of the absorption refrigeration cycle is investigated using mass, momentum and energy balances for the different parts of the system. Some de...

Optical refrigeration may provide the physical basis for solid-state cryocooling. Devices based on this physics would be vibrationless, compact, and free of electromagnetic interference. Having no moving parts and being pumped by a diode lasers, optical refrigerators would be rugged with operating lifetimes of years. Experiments at Los Alamos National Laboratory have demonstrated the basic phys...

  A refrigeration cycle is a chain of various pieces of equipment including compressors, condensers, evaporators, and expansion devices each of which takes on a particular thermodynamic process duty in the cycle that eventually results in the production of the required refrigeration. The results of optimized mixed refrigerant cycles (MRCs) in Part I show that the configuration of MRC is an eff...

Ever since the renaissance of transcritical R744 systems in the late 1980s, ejectors have been considered to improve energy efficiencies. However, the invention of the ejector dates back far longer. This review paper gives an overview of historical and recent developments regarding air-conditioning and refrigeration systems that use ejectors. More than 150 ejector papers available in the open l...