In this paper a gas turbine power plant including air preheater (recuperator), heat recovery steam generator and air cooler system was modeled. Eight parameters were selected as the design variables.  Fast and elitist non-dominated sorting genetic algorithm (NSGA-II) was applied (to maximize the exergy efficiency and to minimize the total cost rate) for the mentioned cogeneration system. Th...

TThe present paper evaluates the plan of combustion air pre-heater installation on the fired heater from thermodynamics and thermos-economics point of view. As a real case study, one of the fired heaters (H_101) of Distillation unit in Tehran Oil Refinery, Iran, is intended. With applying an air pre-heater in this study, flue gases temperature falls down from 430 ºC to 200ºCand combustion a...

The main goal of this paper is to analyze the exergy losses during the shock and rarefaction wave of hydrogen-air mixture. First, detonation parameters pressure, temperature, density, and species mass fraction are calculated for three cases where the hydrogen mass fraction in air is 1.5%, 2.5%, and 5%. Then, exergy efficiency is used as objective criteria of performance evaluation. A two-dimens...

The use of exergy to correlate energy-utilization efficiencies and energy research investments is described. Specifically, energy and exergy losses are compared with energy research and development expenditures, demonstrating that the latter correlates with energy losses, even though it would be more sensible to allocate energy research and development funding in line with exergy losses, as the...

The paper illustrates some aspects of energy conversion processes during underground electric train operation. Energy conversion processes are explained using exergy, in order to support transport system sustainability. Loss of exergy reflects a loss of potential of energy to do work. Following the notion that life in Nature demonstrates sustainable energy conversion, we approach the sustainabi...

In this research, a pilot study and analysis of an innovative multi-channel photovoltaic/thermal (MCPV/T) system in a geographic location (35° 44' 35'' N, 50° 57' 25'' E) has been carried out. This system consists of integrating a photovoltaic panel and two PV/T heat-sink converters. The total electrical, exergy and energy efficiencies of the system at air flow rate of 0.005 kg/s and radiation ...

A new method of optimization on linear parabolic solar collectors using exergy analysis is presented. A comprehensive mathematical modeling of thermal and optical performance is simulated and geometrical and thermodynamic parameters were assumed as optimization variables. By applying a derived expression for exergy efficiency, exergy losses were generated and the optimum design and operating co...

Exergy analysis emboldens in cases that all the inefficiencies and bottlenecks to improve energy systems are to be addressed. In this study, a novel vapor compression air dehumidifier integrated with an auxiliary heat exchanger in series arrangement with the main condenser in order to mitigate the reheat coil, and an extra mixing box to recover the ventilated air heat has been introduced. A com...

An experimental and theoretical energy and exergy analysis was conducted for a cylindrical cavity receiver employed in a parabolic dish collector. Based on simultaneous energy and exergy analysis, the receiver average wall temperature and overall heat transfer coefficient were determined. A simplified Nusselt number for Heat Transfer Fluid (HTF) through the receiver as a function of Reynolds an...