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BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI
Publicat de
Universitatea Tehnică „Gheorghe Asachi“ din Iaşi,
Tomul LVIII (LXII), Fasc. 4, 2012
Secţia
CONSTRUCŢII DE MAŞINI
ANALYSIS OF DIESEL ENGINE OPERATION ON METHANE,
METHANOL AND DIESEL FUELS
BY
ADRIAN SABĂU ∗ , CONSTANTIN DUMITRACHE
and MIHAELA BARHALESCU
Received: March 23, 2012
Accepted for publication: April 15, 2012
Constanţa Maritime University,
Department of Mechanical Engineering
Abstract. In this paper is presented the results of the second-law analysis
of engine operation with diesel fuel compared with the results of a similar
analysis for cases where a light, gaseous (CH4) and an oxygenated (CH3OH)
fuel are used. The overall energy and availability balance during an engine cycle
are studied analytically. It is shown theoretically that the decomposition of
lighter molecules leads to less entropy generation compared to heavier fuels.
Key words: key irreversibility, equilibrium, availability, second-law
efficiency, combustion.
1. Introduction
Recent studies (Dunbar&Lior, 1994) show that almost 1/3 of the energy
of fuel is destroyed during the combustion process in power generation. This
has caused a renewed interest in exergy analyses, since effective management
and optimization of thermal systems is emerging as a major modern technical
problem (Bejan et al., 1996). For internal combustion engines, early work
(Abraham et al., 1994) on the evaluation of the global engine operation using of
second-law techniques was followed by detailed availability and irreversibility
calculations during the engine cycle (Rakopoulos et al.,1993). Second-law
∗ Corresponding author: e-mail: ady.sabau@gmail.com