In this study, modeling and thermodynamic analysis of the combined double flash geothermal cycle generation was conducted using zeotropic fluid as working in Organic Rankine Cycle (ORC). The performed based on first second laws thermodynamics. Hexane, cyclohexane, isohexane, R245fa, R236ea exhibit good performance at higher temperatures. three fluids—hexane, isohexane—were used. First, model re...

This paper describes a modification of vapor compression cycles with a novel Heat-Mass-Exchange (HME) technique. The HME unit reduces irreversibilities by utilizing the heat generated in the compressor to pump a portion of the refrigerant. It also allows the utilization of low grade heat sources (say, at 100°C) to supply a portion of the required thermodynamic work. Calculations indicate that e...

Heat pump technology has been rapidly developed recently as a clean and efficient heating method. Continuous capacity modulation of heat pumps is necessary for enhancing room thermal comfort and reducing start-stop losses. A novel capacity modulation method for the scroll compressor heat pump system based on refrigerant injection and refrigerant release is proposed. The experiments indicate the...

The TEWI analysis of residential heat pumps shows that it is sensitive to refrigerant emissions and mainly dependent on the seasonal coefficient of performance of the heating unit. Otherwise for countries where electricity is mainly produced by a combination of nuclear-power and hydro-power, the direct emissions become not negligible compared to the indirect emissions. Both direct and indirect ...

The direct impact of refrigerants on the environment is largely dependent magnitude global warming potential (GWP) values. In this regard, fluids with low GWP are very important for environment. Commercial refrigeration accounts about a third world's HFC use. R404A derived near an azeotropic mixture. refrigerant widely used in commercial systems, especially supermarkets. As result use cooling s...

An H-magic labeling in a H-decomposable graph G is a bijection f : V (G) ∪ E(G) → {1, 2, ..., p + q} such that for every copy H in the decomposition, ΣνεV(H) f(v) +  ΣeεE(H) f(e) is constant. f is said to be H-E-super magic if f(E(G)) = {1, 2, · · · , q}. A family of subgraphs H1,H2, · · · ,Hh of G is a mixed cycle-decomposition of G if every subgraph Hi is isomorphic to some cycle Ck, for k ≥ ...

An H-magic labeling in a H-decomposable graph G is a bijection f : V (G) ∪ E(G) → {1, 2, ..., p + q} such that for every copy H in the decomposition, ∑νεV (H) f(v) + ∑νεE (H) f(e) is constant. f is said to be H-E-super magic if f(E(G)) = {1, 2, · · · , q}. A family of subgraphs H1,H2, · · · ,Hh of G is a mixed cycle-decomposition of G if every subgraph Hi is isomorphic to some cycle Ck, for k ≥...

The capillary tube/suction line heat exchanger (SLHX) is widely used in small refrigeration systems. The refrigerant flowing in the SLHX experiences frictional and accelerational head losses, flashing, and heat transfer simultaneously. The simulation of refrigerant flow through SLHX is important since this will help engineers analyze and optimize the SLHX incorporated in a refrigeration system....

The present paper summarizes the activities at LTT-Erlangen on the field of thermophysical properties research for pure refrigerants and refrigerant mixtures. For the characterization of their thermophysical properties dynamic light scattering (DLS) has been intensively applied as a key tool during the past two decades. Beside a representation of the essential features of DLS for the determinat...