An expander is employed to replace a throttling valve in a heat pump system of the convention order to further improve the efficiency of the system by recovering partial expansion work to dec consume of the system. Due to large expansion ratios of conventional refrigerants, a tw one-stage expand total losses, which are th efficiency efficiently.

A built experimental set-up was employed for the estimation of the solid-liquid equilibria of alternative refrigerants systems. The behavior of carbon dioxide + 1,3,3,3-tetrafluoropropene (CO2 + R1234ze(E)) was measured down to temperatures of 160.0 K. The results obtained for the mixtures were interpreted by means of the Schröder equation.

Air conditioning and refrigeration have become necessary in modern life, accounting for more than 7.8% of greenhouse gases (GHG) emitted globally. Reducing the environmental impact these systems is crucial meeting global GHG emission targets. Two principal directions must be considered to reduce air systems. Firstly, reducing direct effect by looking at less harmful refrigerants secondly, indir...

The first and second law of thermodynamics are applied to an ionic-liquid (IL) based absorption refrigeration system for high power electronics cooling. The IL is a salt in a liquid state usually with an organic cation and inorganic anion. It provides an alternative to the normally toxic working fluids used in the chemical compression loop, such as ammonia in conventional absorption systems. Th...

A new dual-fluid concept was studied that could eventually find application for cold-gas propulsion for small space satellites or other constant flow applications. In basic form, the concept uses two different refrigerant working fluids, each having a different saturation vapor pressure. The higher vapor pressure refrigerant remains in the saturation phase and is used to pressurize the lower sa...