Title Page
ABSTRACT
국문 초록
PREFACE
Contents
NOMENCLATURE 15
CHAPTER 1. INTRODUCTION 17
1.1. Necessity of using ammonia 17
1.1.1. Efficiency (Transportation, energy density) 17
1.2. Considerations for using ammonia 18
1.2.1. Low activity 18
1.2.2. NOx emission[이미지참조] 19
1.2.3. Toxicity & Safety 19
1.3. Objective of this study 20
CHAPTER 2. Experimental Approach 22
2.1. Ammonia cracking 22
2.2. Experimental setup 23
2.3. Numerical analysis 26
2.3.1. PSR(Perfectly Stirred Reactor) model & SLF(Steady Laminar Flamelet) model 26
CHAPTER 3. DISCUSSION 28
3.1. Lean blowout limit 28
3.2. Flame shape - Tendency of non-premixed flame of ammonia-hydrogen-nitrogen-air mixture 29
3.3. Ignition delay time, laminar flame speed 32
3.4. Lewis number effect 34
3.5. NOx result[이미지참조] 36
CHAPTER 4. CONCLUSION 39
REFERENCES 41
Table 1. Summary of experimental matrix 26
Table 2. Area fraction of flame (α=0~0.75) 35
Figure 1. NH₃/H₂/N₂ mole fraction of fuel mixture in accordance with α 23
Figure 2. Schematic of a tangential injection burner with an emission measurement system 25
Figure 3. Lean blowout limit at Vt=8, 10, 12m/s along α=0~0.75[이미지참조] 28
Figure 4. Photographs of NH₃/H₂/N₂/Air non-premixed flame at φ=0.8, Vt=10m/s along α=0~0.75[이미지참조] 29
Figure 5. Wall temperature distribution at φ=0.8, Vt=8, 12m/s along α=0~0.75[이미지참조] 31
Figure 6. Ignition delay time of NH₃/H₂/N₂/air mixture at φ=0.8 33
Figure 7. Laminar flame speed versus α for NH₃/H₂/N₂/Air mixture.33
Figure 8. Le of NH₃/H₂/N₂ mixture 34
Figure 9. Binary image of flame with grayscale, averaging process 35
Figure 10. Comparison between measured NO and predictions (Dotted: Experiment, Line: Simulation) 36
Figure 11. Characteristic chemical time scale (τchem=1/χst,a) of the partially cracked ammonia/air counterflow flame[이미지참조] 38