Comparison of Biodiesel Performance Based on HCCI Engine Simulation Using Detailed Mechanism with On-the-fly Reduction

Abstract

Biodiesel is a complex mixture of long-chain methyl esters. Accurate numerical study of biodiesel combustion requires detailed chemistry of large biodiesel surrogates representing realistic biodiesel fuels. However, the detailed kinetic mechanisms for large biodiesel surrogates involve large number of species and reactions, leading to extremely expensive or even infeasible computation when incorporated in engine CFD (computational fluid dynamics) calculations. In this study, the scheme of on-the-fly mechanism reduction incorporated with engine CFD code KIVA-3V is first extended to two large biodiesel surrogate mechanisms, namely methyl decanoate and methyl-9-decenoate. Detailed combustion and engine performance characterization for biodiesel fuels are enabled, and the computational intensity is significantly reduced with satisfactory accuracy. In the simulations, lower CO and NO emissions and lower engine power are observed for biodiesel surrogates. Combustion features such as early oxidation of ester groups are also well captured. This work provides the insight to study combustion and engine operation of complex fuels on the basis of detailed chemistry with efficient mechanism reduction technique.

Autoignition of methyl butanoate under engine relevant conditions

“…Ra and Reitz [27] used methyl butanoate as a component in a multicomponent surrogate reaction mechanism to simulate engine combustion with multi-component fuels. There are several other studies that have used methyl butanoate based kinetic schemes in numerical investigations on engine combustion, e.g., [6,[28][29][30][31]. Boehman and co-workers have carried out motored engine experiments on esters and blends of esters with other fuels [32][33][34][35].…”

Comparative Numerical Study of Four Biodiesel Surrogates for Application on Diesel 0D Phenomenological Modeling

“…The surrogates used in this study are, respectively, methyl butanoate, ethyl butyrate, methyl decanoate, and methyl 9 decenoate. These four surrogates were chosen firstly because of the high amount of work on their combustion kinetics and study as biodiesel surrogates [33][34][35][36] and secondly for the wildly availability of their validated reduced mechanisms data. The thermodynamic data for each surrogate were taken, respectively, from the work of Liu et al [37] for methyl butanoate, Herbinet et al for methyl decanoate [38], Luo et al [39] for methyl 9 decenoate, and the work of Goos et al [40] for methyl butyrate.…”

Mimicking Complexity - Automatic Generation of Models for the Development of Self-adaptive Systems

“…Other simulation tools focus on different goals such as finding optimal values of engine parameters (Curto-Risso et al, 2009), comparing fuel performances (Zhang et al, 2012) or leading studies on the behavior of a specific type of engine (Zhao et al, 2008). These models are highly specific and demands a heavy work of implementation and parametrization.…”