[خثيـر]

This modest work will never be accomplished without my God (Allah). Almighty with His blessings and His power that work within me and also without the people behind my life for inspiring, guiding and accompanying me through thick and thin. My foremost thank goes to my thesis adviser Pr. ..... Without him, this dissertation would not have been possible. I thank him for his patience and encouragement that carried me on through difficult times, and for his insights and suggestions that helped to shape my research skills. His valuable feedback contributed greatly to this dissertation. I am grateful to ............ , who introduced and helped me to start. He advised me and helped me in various aspects of my research. He is the one that I can always count on to discuss the tiniest details of . Without his help this work may not see the life. I would like also to thank all ...... staff specially ......... I would like to thank ......, Ph.D Candidate in the Institute of Internal Combustion Engines School of Energy and Power Engineering at the Xi'an Jiaotong University, P.R. China, for sending me his experimental data and for the valuable discussion that we have exchanged. I thank also the professor................professor at school of power and power engineering at the Xi'an Jiaotong University for permit us to publish and use their experimental data. I thank the rest of my thesis committee members, I have a great honor to be face to.....and. for inviting me to shear with them a rich debate and discussion in a various science and society subject. Their ideas have changed my vision toward the life. I thank also all my friends in .laboratory for the valuable discussion on Math, Combustion, turbulence, literature, religion, philosophy...ect. Really I feel the better meaning of the life with them. Last but not least, my family for always being there when I needed them most, and for supporting me and my simulations through all these years.