International Science Community Association Research Journal of Recent Sciences 2277 - 2502 1 8 2012 August 2 Numerical Analysis of Direct Injection Diesel Engine Combustion using Extended Coherent Flame 3-Zone Model 1 9 EN Renganathan Manimaran 1 Thermal and Automotive Division, School of Mechanical and Building Sciences, VIT University, Vellore, INDIA ThundilKaruppaRaj Rajagopal 2 Energy Division, School of Mechanical and Building Sciences, VIT University, Vellore, INDIA SenthilKumar K. 3 > Research Paper 2012 3 15 2012 August 2 Several applications have proven the reliability of using multi-dimensional CFD tools to assist in diesel engine research, design and development. CFD tools are extensively used to reveal details about invisible in-cylinder processes of diesel combustion so that guidance can be provided to improve engine designs in terms of emissions reduction and fuel economy. Innovative combustion concepts can be evaluated numerically prior to experimental tests to reduce the number of investigated parameters. In this present work, reacting flow simulations were performed in a single cylinder direct injection diesel engine with an improved version of the ECFM-3Z (extended coherent flame model – 3 Zones) model using ES-ICE and STAR-CD codes. Combustion and emission characteristics are studied in a sector of engine cylinder, which eliminates the tedious experimental task with conservation in resources and time. The pressure variations during motoring and firing conditions, temperature and heat release graphs with respect to crank angle are plotted. Mass fractions contours of CO, NO, soot and fuel (C1226) and mixture density contours at TDC are plotted. It is found that higher NOx emissions occur at peak temperatures while soot and CO emissions occur at peak pressures. Copyright@ International Science Community Association