The quantum-mechanical and thermodynamic properties of a three-level molecular cooling cycle are derived. An inadequacy of earlier models is rectified in accounting for the spontaneous emission and absorption associated with the coupling to the coherent driving field via an environmental reservoir. This additional coupling need not be dissipative, and can provide a thermal driving force-the qua...

gas turbines play an important role in supplying power for the country especially in peak electricity load. the main disadvantages are the turbines, they produce large changes are a result of climate change. however, in times of peak electricity grid and at the same time warm months, can produce gas turbines under the effect of ambient temperature, the amount of reduced considerably. the method...

Today, renewable energies are of more interest due to depleting the ozone layer, increasing the cost of fossil fuels and friendliness with the environment. The sun is a great source of energy which is readily accessible. It has many applications in lighting, heating and cooling. In this study the thermal performance of a solar ejector cooling cycle is evaluated using several different working f...

A simple effect one stage ammonia-water absorption cooling system fueled by solar energy is analyzed. The considered system is composed by a parabolic trough collector concentrating solar energy into a tubular receiver for heating water. This is stored in a fully mixed thermal storage tank and used in the vapor generator of the absorption cooling system. Time dependent cooling load is considere...

In order to improve the utilization efficiency of low-temperature heat sources, a new combined cooling and power system using ammonia–water is proposed. The combines Kalina cycle with absorption refrigeration cycle, in which waste serves as source cycle. steady-state mathematical model established detail first, then simulation results design condition are obtained, show that thermal exergy can ...

Refrigeration cogeneration systems which generate power alongside with cooling improve energy utilization significantly, because such systems offer a more reasonable arrangement of energy and exergy ‘‘flows’’ within the system, which results in lower fuel consumption as compared to the separate generation of power and cooling or heating. This paper proposes several novel systems of that type, b...

This paper aims at studying a trigeneration system, based on an internal combustion engine and a steam ejector refrigeration system. The designed cycle is to generate cooling and heating energies, and supply power simultaneously. The cycle is studied from thermodynamics point of view and for this purpose, the first law of thermodynamics is applied to all components of the cycle. The efficiency ...

A novel solar-based combined system which is consisting of a concentrated PV, a double effect LiBr-H2O absorption chiller, and a Proton Exchange Membrane (PEM) is proposed for hydrogen production. A portion of the received energy is recovered to run a double effect absorption chiller and the rest is turned into electricity, being consumed in the PEM electrolyzer for hydrogen producti...