TY - JFULL AU - L. V. Fui and A. Ulugbek and S. S. Dol PY - 2014/8/ TI - Hybrid RANS-LES Simulation of In-Cylinder Air Flow for Different Engine Speeds at Fixed Intake Flow Pressure T2 - International Journal of Aerospace and Mechanical Engineering SP - 1329 EP - 1333 VL - 8 SN - 1307-6892 UR - https://publications.waset.org/pdf/10000124 PU - World Academy of Science, Engineering and Technology NX - Open Science Index 91, 2014 N2 - The in-cylinder flow and mixture formations are significant in view of today’s increasing concern on environmental issues and stringent emission regulations. In this paper, the numerical simulations of a SI engine at different engine speeds (2000-5000 rpm) at fixed intake flow pressure of 1 bar are studied using the AVL FIRE software. The simulation results show that when the engine speed at fixed intake flow pressure is increased, the volumetric efficiency of the engine decreases. This is due to a richer fuel conditions near the engine cylinder wall when engine speed is increased. Significant effects of impingement are also noted on the upper and side walls of the engine cylinder. These variations in mixture formation before ignition could affect the thermodynamics efficiency and specific fuel consumption that would lead to a reduced engine performance. ER -