FLAME PROPAGATION IN SPARK IGNITION ENGINE COMBUSTION PROCESS USING COMPUTATIONAL FLUID DYNAMICS (CFD) HANIF BIN KASMANI

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1 FLAME PROPAGATION IN SPARK IGNITION ENGINE COMBUSTION PROCESS USING COMPUTATIONAL FLUID DYNAMICS (CFD) HANIF BIN KASMANI Report submitted in partial of the requirements for the award of the degree of Bachelor of Mechanical Engineering with Automotive Engineering Faculty of Mechanical Engineering UNIVERSITI MALAYSIA PAHANG MAY 2011

2 UNIVERSITI MALAYSIA PAHANG JUDUL: BORANG PENGESAHAN STATUS TESIS FLAME PROPAGATION IN SPARK IGNITION ENGINE COMBUSTION PROCESS USING COMPUTAUIONAL FLUID DYNAMICS (CFD) SESI PENGAJIAN: 2010/2011 Saya HANIF BIN KASMANI ( ) (HURUF BESAR) mengaku membenarkan tesis (Sarjana Muda/Sarjana /Doktor Falsafah)* ini disimpan di Perpustakaan dengan syarat-syarat kegunaan seperti berikut: 1. Tesis adalah hakmilik Universiti Malaysia Pahang (UMP). 2. Perpustakaan dibenarkan membuat salinan untuk tujuan pengajian sahaja. 3. Perpustakaan dibenarkan membuat salinan tesis ini sebagai bahan pertukaran antara institusi pengajian tinggi. 4. **Sila tandakan ( ) SULIT TERHAD (Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia seperti yang termaktub di dalam AKTA RAHSIA RASMI 1972) (Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan) TIDAK TERHAD Disahkan oleh: (TANDATANGAN PENULIS) Alamat Tetap: (TANDATANGAN PENYELIA) Nama Penyelia: 1094 JLN SEMARAK 20, MR. MOHD FADZIL RAHIM TMN PANCHOR JAYA, SEREMBAN, NEGERI SEMBILAN. Tarikh: 30 MAY 2011 Tarikh: 30 MAY 2011 CATATAN:* Potong yang tidak berkenaan. ** Jika tesis ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasa/organisasi berkenaan dengan menyatakan sekali tempoh tesis ini perlu dikelaskan sebagai atau TERHAD. Tesis dimaksudkan sebagai tesis bagi Ijazah doktor Falsafah dan Sarjana secara Penyelidikan, atau disertasi bagi pengajian secara kerja kursus dan penyelidikan, atau Laporan Projek Sarjana Muda (PSM).

3 viii TABLE OF CONTENTS SUPERVISOR S DECLARATION STUDENT S DECLARATION DEDICATION ACKNOWLEDGEMENT ABSTRACT ABSTRAK TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES LIST OF SYMBOLS LIST OF ABBREVIATIONS Page ii iii iv v vi vii viii xi xii xiii xiv CHAPTER 1 INTRODUCTION 1.1 Background of Study Problem Statement Objectives of the Project Project Scopes Flow Chart Organization of Thesis 3 4 CHAPTER 2 LITERRATURE REVIEW 2.1 Introduction Combustion In Spark Ignition Engine Ignition and Flame Development Flame Propagation in SI Engine Flame Termination 2.3 Kernel Formation

4 ix 2.4 Combustion Modeling Using CFD CFD Approach in SI Simulation by Previous Reseachers Effect of Various Parameters into Flame radius Summary 15 CHAPTER 3 METHODOLOGY 3.1 Introduction Baseline Engine Specification Engine Modeling The Governing Equation for CFD Mass Conservation Equation Momentum conservation Equation Energy Conservation Equation Mesh Generation Solution Setup Initial Condition Boundary Condition Setup Input Data for Premix Flame Radius Measurement Method Technical Specification of Workstation Validation Method Limitations of Current Study CHAPTER 4 RESULTS AND DISCUSSION 4.1 Introduction Effect Of Iteration on Cylinder Pressure, Flame Propagation and Flame Radius Cylinder Pressure Visualization of Flame Propagation In Terms

5 x Of Progress Variable Flame Radius Computational Time Result Justification Model Geometry and Input Data Properties Processor Limitation Summary CHAPTER 5 CONCLUSSION AND RECOMMENDATIONS 5.1 Conclusion Recommendations 39 REFERENCES 40 APPENDICES A Simulation Data 41

6 xi LIST OF TABLES Table No. Title Page 3.1 Mitsubishi Magma 4G15 1.5L engine specification Initial condition at 2000 rpm Boundary condition at 2000 rpm Input data for premix-mixture properties Technical specification of the computers used for 26 simulation study 4.1 Comparison of peak pressure value Peak pressure timing Total computational time for both cases 36

7 xii LIST OF FIGURES Table No. Title Page 1.1 Project flow chart Cylinder pressure in the combustion chamber of a 6 SI engine as a function of crank angle 2.2 Average flame speed Initial flame kernel temperature Initial flame kernel radius Flame kernel radius with various engine speeds Flame kernel radius with various intake manifold Flame kernel radius with various air fuel mixture Isometric view of engine modeling Mesh generation Points within combustion chamber Comparison of measured and simulated cylinder 29 Pressure for each case 4.2 Cylinder pressure in the combustion chamber of a 31 SI engine as a function of crank angler 4.3 Visualization of flame propagation Flame kernel with 1500 iterations Assumption of flame propagation structure Flame radius using different RPM 35

8 xiii LIST OF SYMBOLS e F i h J j K m j m S h u gi ij Specific total energy External body force in i direction Sensible enthalpy Diffusion flux of species j Effective conductivity Mass fraction of species j The rate of mass of the object generated in the system Additional volumetric heat sources The jth Cartesian component of instantaneous velocity Fluid dynamic viscosity Fluid density Static pressure Gravitational body force Stressor pressure Kronecker delta

9 xiv LIST OF ABBREVIATION 3D ABDC ATDC BBDC BTDC CA CFD CPU DNS DSM EGR EVM K LES NLEVM Pa RANS RPM TDC SI Three dimensional After bottom dead center After top dead center Before bottom dead center Before top dead center Crank angle Computational Fluid Dynamic Central processing unit Direct numerical simulation Differential stress models Exhaust gas recirculation Eddy viscosity models Kelvin Large-eddy simulation Non-linear eddy-viscosity models Pascal Reynolds-Average Navier Stokes Revolution per minute Top dead center Spark ignition