Nowadays, the most common way to improve energy conversion efficiency is the integration of different systems, thus achieving a better exploitation of the available exergy potential (e.g. combined cycles, cogeneration, ...). Hydraulic energy is commonly considered to be almost completely exploited by producing power in hydroelectric plants. Aim of this paper is to analyse the possible integration of hydraulic energy sources with conventional, fossil fuel based systems: in particular, power plants based on the combination of a hydraulic air compressor (HAC) and a gas turbine are considered. In a HAC, air is entrained into a water flow in a downcoming pipe and compressed. Once separated from the water in a "stilling chamber" at the bottom of the downpipe, the compressed air is supplied to a combustion chamber and then to a conventional gas turbine expander. An attractive characteristic of HACs is the capability, in principle, to perform an isothermal air compression instead of an adiabatic one, as in conventional compressors. In the present work, a thermodynamic analysis is presented of HAC - gas turbine energy conversion systems, which are compared with conventional hydroelectric and gas turbine power plants. The calculated performance levels of such systems are comparable to those of combined cycle plants, making further technical and economical investigations quite interesting.
Thermodynamic Analysis of Hydraulic Air Compressor-Gas Turbine Power Plants
BIDINI, Gianni;GRIMALDI, Carlo Nazareno;POSTRIOTI, Lucio
1997
Abstract
Nowadays, the most common way to improve energy conversion efficiency is the integration of different systems, thus achieving a better exploitation of the available exergy potential (e.g. combined cycles, cogeneration, ...). Hydraulic energy is commonly considered to be almost completely exploited by producing power in hydroelectric plants. Aim of this paper is to analyse the possible integration of hydraulic energy sources with conventional, fossil fuel based systems: in particular, power plants based on the combination of a hydraulic air compressor (HAC) and a gas turbine are considered. In a HAC, air is entrained into a water flow in a downcoming pipe and compressed. Once separated from the water in a "stilling chamber" at the bottom of the downpipe, the compressed air is supplied to a combustion chamber and then to a conventional gas turbine expander. An attractive characteristic of HACs is the capability, in principle, to perform an isothermal air compression instead of an adiabatic one, as in conventional compressors. In the present work, a thermodynamic analysis is presented of HAC - gas turbine energy conversion systems, which are compared with conventional hydroelectric and gas turbine power plants. The calculated performance levels of such systems are comparable to those of combined cycle plants, making further technical and economical investigations quite interesting.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
