A comprehensive analysis of the kinetic mechanisms for ethanol oxidation is presented which is driven by the increasing demand for alternative fuels used in combustion devices, such as internal combustion engines and gas turbines. In order to perform multidimensional CFD simulations of such devices in a computational time of practical interest, the air-ethanol kinetic models should be the proper compromise between accuracy and efficiency. In this work, three detailed reaction mechanisms, made up of 383, 235 and 142 reversible reactions and 57, 46 and 33 chemical species, respectively, are considered as a starting point. Simplified schemes have been obtained from these mechanisms by using a Computational Singular Perturbation methodology. The detailed and simplified mechanisms have been analysed in order to gain understanding of the ethanol kinetic behaviour and to identify the key reactions which are responsible of the fundamental characteristics of the fuel oxidation. Finally, these mechanisms have been employed to simulate zero-dimensional and multi-dimensional configurations of a constant volume batch reactor and an HCCI engine, respectively. The results were compared against each other, in order to show the accuracy and the efficiency of the simplified mechanisms versus the detailed ones.
On the Simplified Ethanol Kinetics by means of a Computational Singular Perturbation Approach
VIGGIANO, ANNARITA;MAGI, Vinicio
2010-01-01
Abstract
A comprehensive analysis of the kinetic mechanisms for ethanol oxidation is presented which is driven by the increasing demand for alternative fuels used in combustion devices, such as internal combustion engines and gas turbines. In order to perform multidimensional CFD simulations of such devices in a computational time of practical interest, the air-ethanol kinetic models should be the proper compromise between accuracy and efficiency. In this work, three detailed reaction mechanisms, made up of 383, 235 and 142 reversible reactions and 57, 46 and 33 chemical species, respectively, are considered as a starting point. Simplified schemes have been obtained from these mechanisms by using a Computational Singular Perturbation methodology. The detailed and simplified mechanisms have been analysed in order to gain understanding of the ethanol kinetic behaviour and to identify the key reactions which are responsible of the fundamental characteristics of the fuel oxidation. Finally, these mechanisms have been employed to simulate zero-dimensional and multi-dimensional configurations of a constant volume batch reactor and an HCCI engine, respectively. The results were compared against each other, in order to show the accuracy and the efficiency of the simplified mechanisms versus the detailed ones.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
