An energy flow model of an airport terminal’s HVAC system is established in this paper. Based on energy flow model, the exergy efficiency, exergy loss and exergy cost distribution ratio of each component are calculated and analyzed by the energy flow model. Optimization method and exergy balance equations are used to calculate the lowest exergy loss of HVAC system under different operation cond...

Energy, exergy and exergoeconomic (3E) evaluation are performed to assess the performance of a NH3/H2O cycle integrated with parabolic trough solar collectors (PTSC). To provide continuous electricity produced by generator when solar beam radiation is insufficient a stabilizer temperature subsystem is utilized. The major thermodynamic parameters and climate conditions variations are selected to...

Exergy is applied to the Swedish energy supply system for the period 1970–2013. Exergy flow diagrams for the systems of electricity and district heating as well as for the total supply system of energy and material resources for 2012 are presented. The share of renewable use has increased in both electricity and district heat production. The resource use is discussed in four sectors: residentia...

heat recuperation is often used to improve the overall cycle efficiency of gas turbines. however, generally in small- scale gas turbines, it has a negative effect on turbine inlet temperature, pressure ratio and pressure drops, and thus decreases the overall cycle efficiency. in this paper, a thermodynamic model is performed to evaluate recovered heat as a function of heat exchanger effectivene...

in this paper, a new combined power and refrigeration cycle is proposed, which combines the rankin power cycle and the ejector refrigeration cycle. this combined cycle produces both power output and refrigeration output simultaneously. this cycle is driven by the flue gas of gas turbines, industrial waste heats, solar energy and geothermal energy. an exergy analysis is performed to guide the th...

The paper addresses the problem of the existence and quantification of the exergy of non-equilibrium systems. Assuming that both energy and exergy are a priori concepts, the Gibbs “available energy” A is calculated for arbitrary temperature or concentration distributions across the body, with an accuracy that depends only on the information one has of the initial distribution. It is shown that ...

In this paper, performance analysis of a hybrid photovoltaic-thermal (PV/T) greenhouse air heater and dryer has been carried out. Analytical expressions have been developed for • greenhouse air temperature, instantaneous and overall energy and exergy efficiencies for without load and • instantaneous exergy efficiency with load under forced mode operation. An experimental validation has been car...

Second-law analysis (SLA) is an important concept in thermodynamics, which basically assesses energy by its value in terms of its convertibility from one form to another. Highly-valued forms of energy in this context are called exergy, defined as those energies from which the maximum theoretical work is obtainable when the energy is interacting with the environment to equilibrium (see Moran et ...

A conventional exergy analysis can highlight the main components having high thermodynamic inefficiencies, but cannot consider the interactions among components or the true potential for the improvement of each component. By splitting the exergy destruction into endogenous/exogenous and avoidable/unavoidable parts, the advanced exergy analysis is capable of providing additional information to c...