Energy, entropy and exergy concepts come from thermodynamics and are applicable to all fields of science and engineering. Therefore, this article intends to provide background for better understanding of these concepts and their differences among various classes of life support systems with a diverse coverage. It also covers the basic principles, general definitions and practical applications a...

The use of zeotropic mixtures in well-designed heat pump cycles enables considerable performance improvements. Temperature glide matching the exchange processes and recovery expansion losses by internal decrease exergy destruction yield higher cycle performances. A case study for supply to district heating is presented, indicating increases COP from 4.3 a pure fluid standard 5.2 mixture with op...

This paper aims to provide comprehensive 4E (energy, exergy, exergoeconomic, and exergoenvironmental) advanced exergy analyses of the Refrigeration Cycle (RC) Heat Recovery (HRRC) comparison performance with R744 (CO2) R744A (N2O) working fluids. Moreover, multi-objective optimization systems has been considered define optimal conditions best cycle from various perspectives. In HRRC, heat recov...

In this paper, the exergoeconomic analysis was conducted to an existing ultra-supercritical coal-fired power plant in China to understand the cost-formation process, to evaluate the economic performance of each component and to find possible solutions for more cost-effective designs. The total revenue requirement (TRR) and the specific exergy costing (SPECO) methods were applied for economic an...

In Kalina power generation as well as vapor absorption and refrigeration systems ammonia-water mixture has been used as working fluids. Unlike for pure components, binary mixtures additionally need mixture concentration to solve thermodynamic properties. A flowchart is developed to understand the computations of the properties. The thermodynamic properties for ammonia-water mixture have been ge...

The vitality of the society is strongly depending on the management of physical, environmental and human resources. The dilemma of the modern society can be stated: misuse of physical resources from poor understanding of concepts such as exergy, misuse of nature from ignorance of ecology and misuse of people or human intelligence from lack of democracy. Exergy is a well-established concept in e...

Metal Foam-enhanced Cascaded Thermal Energy Storage (MF-CTES) has been proposed to solve the problem of poor heat transfer during heat exchange process, which is caused by unavoidable decrease of temperature differences. This paper conducts a theoretical study examining the overall thermal performance of STES (Single-stage Thermal Energy Storage), CTES (Cascaded Thermal Energy Storage) and MF-C...

The application of ecological exergy as a suitable system-oriented development indicator of ecosystems and the estimation proposals from biomass are revised. DNA contents (C-values) of several groups of organisms are figured, either determined by flow cytometry or taken from literature. The applicability of DNA contents for determination of weighing factors to estimate ecological exergy from th...

This paper analyzes the energetic and exergy performance of an active magnetic regenerative refrigerator using water-based Al2O3 nanofluids as heat transfer fluids. A 1D numerical model has been extensively used to quantify the exergy performance of a system composed of a parallel-plate regenerator, magnetic source, pump, heat exchangers and control valves. Al2O3-water based nanofluids are test...

A thermodynamic model of a thermoelectric generator-driven thermoelectric heat pump (TEG-TEH) combined device is established considering the Thomson effect and the temperature dependence of the thermoelectric properties based on non-equilibrium thermodynamics. Energy analysis and exergy analysis are performed. New expressions for heating load, maximum working temperature difference, coefficient...