Investigating the effect of combustion properties on the accumulated heat release of DI engines at rated EGR levels using the ANN approach

Abstract This study is dedicated to explore the effect of in-cylinder combustion parameters on the accumulated heat release at rated EGR levels using the CFD implemented code data which were coupled to the artificial neural network (ANN) approach to construct a model to predict the accumulated heat release of DI diesel engines. To this end, at two different engine speeds of 3000 and 4000 rpm, crank angle, equivalence ratio, turbulence kinetic energy and temperature varied to obtain the corresponding accumulated heat release data at three EGR levels of 0.2, 0.3 and 0.4. It was discovered that that application of higher EGR is conducive to temperature reduction while it leads to the decreased equivalence ratios. It was also concluded that the accumulated heat increases with equivalence ratio and temperature but decreases with increment of Exhaust Gas Recirculation (EGR) levels. Numerous ANN modeling implementations were carried out using different training algorithms of trainlm , trainscg , traingdx , and trainrp at diversified number of neurons in the single hidden layer. At 17 neuron numbers in the hidden layer, the trainlm method denoted MSE equal to 0.1057 which was the best performance among the various implemented models. The coefficient of determination ( R 2 ) values equal to 0.99 and 0.99 were obtained for training and testing phases. The obtained results confirm the promising ability of ANN for the prognostication of accumulated heat release of DI engines.

[1]  A. Gosman,et al.  Aspects of computer simulation of liquid-fuelled combustors , 1981 .

[2]  A. Benkenida,et al.  The 3-Zones Extended Coherent Flame Model (Ecfm3z) for Computing Premixed/Diffusion Combustion , 2004 .

[3]  Raouf Mobasheri,et al.  Analysis the effect of advanced injection strategies on engine performance and pollutant emissions in a heavy duty DI-diesel engine by CFD modeling , 2012 .

[4]  Henk A. van der Vorst,et al.  Bi-CGSTAB: A Fast and Smoothly Converging Variant of Bi-CG for the Solution of Nonsymmetric Linear Systems , 1992, SIAM J. Sci. Comput..

[5]  A. Torregrosa,et al.  Experimental assessment for instantaneous temperature and heat flux measurements under Diesel motored engine conditions , 2012 .

[6]  Rolf D. Reitz,et al.  Modeling the Effect of Engine Speed on the Combustion Process and Emissions in a DI Diesel Engine , 1996 .

[7]  R. Reitz Modeling atomization processes in high-pressure vaporizing sprays , 1987 .

[8]  C. D. Rakopoulos,et al.  Combustion heat release analysis of ethanol or n-butanol diesel fuel blends in heavy-duty DI diesel engine , 2011 .

[9]  Tadashi Murayama,et al.  Description and Analysis of Diesel Engine Rate of Combustion and Performance Using Wiebe's Functions , 1985 .

[10]  George Kosmadakis,et al.  Critical evaluation of current heat transfer models used in CFD in-cylinder engine simulations and establishment of a comprehensive wall-function formulation , 2010 .

[11]  Adrian Irimescu Convective heat transfer equation for turbulent flow in tubes applied to internal combustion engines operated under motored conditions , 2013 .

[12]  Dimitrios C. Rakopoulos,et al.  Investigation of the combustion of neat cottonseed oil or its neat bio-diesel in a HSDI diesel engine by experimental heat release and statistical analyses , 2010 .

[13]  Dimitrios C. Kyritsis,et al.  Experimental-stochastic investigation of the combustion cyclic variability in HSDI diesel engine using ethanol–diesel fuel blends , 2008 .

[14]  Dimitrios C. Rakopoulos,et al.  Experimental heat release analysis and emissions of a HSDI diesel engine fueled with ethanol–diesel fuel blends , 2007 .

[15]  J G Hawley,et al.  A fully analytical treatment of heat release in diesel engines , 2003 .

[16]  George Kosmadakis,et al.  Heat transfer in HCCI multi-zone modeling: Validation of a new wall heat flux correlation under motoring conditions , 2011 .

[17]  A. Gosman,et al.  Aspects of Computer Simulation of Liquid-Fueled Combustors , 1983 .

[18]  Shigenori Sano,et al.  Diesel engine dynamics modeling based on heat release rate identification , 2011, SICE Annual Conference 2011.

[19]  J G Hawley,et al.  An experimental study of the application of variable-geometry turbocharging and high-pressure common rail to an automotive diesel engine , 2001 .