표제지
목차
Nomenclature 12
Greek Symbols 14
Abstract 15
제1장 서론 19
1.1. 연구 배경 19
1.1.1. 지구의 온난화 19
1.1.2. IMO의 대기오염물질 배출 규제 20
1.1.3. 대체 연료 23
1.2. 수소 가스 사고 및 연구 동향 25
1.2.1. 수소 가스 사고 사례 25
1.2.2. 수소 누출에 관한 연구 동향 26
1.3. 연구 목적 30
1.4. 연구 범위와 논문의 구성 31
제2장 수소 에너지 및 수소연료전지 추진 선박 34
2.1. 수소 에너지의 정의와 특징 34
2.2. 수소 에너지의 저장 37
2.3. 수소연료전지 추진 선박 39
제3장 수치해석 41
3.1. 수소탱크 저장실의 설계 관련 규정 41
3.2. 수소탱크의 모델링 43
3.3. 수소탱크 저장실의 모델링 47
3.4. 수치해석 방법 51
3.4.1. 지배방정식 54
3.4.2. 난류모델 56
3.4.3. 화학종의 수송방정식 60
제4장 수소 누출 CFD의 유효성 61
4.1. 수소 누출에 관한 CFD 적합성 검증 61
4.2. 경계조건 및 격자 의존성 검토 68
4.2.1. 수소탱크 저장실의 경계조건 68
4.2.2. 수소탱크 저장실의 격자 생성 및 격자 의존성 검토 73
제5장 수소 정체부 및 급·배기 위치별 환기 성능 79
5.1. 천장 정점각(A)에 따른 누출 수소 정체부 79
5.1.1. 현존선 천장 정점각(A)에서의 수소 정체부 79
5.1.2. 천장 정점각(A)의 감소에 따른 수소 정체부 85
5.2. 급·배기구 위치에 따른 환기 성능 96
5.2.1. 급기구 위치에 따른 수소 몰분율의 변화 및 환기 성능 96
5.2.2. 배기구 위치에 따른 수소 몰분율의 변화 및 환기 성능 107
5.2.3. 환기 성능을 높이기 위한 급·배기구의 최적 위치 120
제6장 통풍량 및 환기 방식별 환기 성능 122
6.1. 통풍량 증가에 따른 환기 성능 122
6.1.1. 수소탱크 저장실 내의 수소 농도 123
6.1.2. 수소탱크 저장실 내의 속도 분포 133
6.2. 환기 방식에 따른 환기 성능 142
6.2.1. 천장 정점각(A) 177.7°에서의 환기 성능 144
6.2.2. 천장 정점각(A) 120°에서의 환기 성능 148
제7장 결론 154
참고 문헌 157
부록 163
부록 A 163
부록 B 168
Table 1.1. Main Regulatory content of MARPOL annex VI 22
Table 1.2. NOX Emission Regulation of IMO[이미지참조] 22
Table 2.1. Specification of hydrogen property 35
Table 2.2. Total risk assessment by fuel types 36
Table 3.1. Specifications for LNG storage tank of E-ship 44
Table 3.2. The empirical constant value of the standard k-ε model equation 59
Table 4.1. The location of the hydrogen sensors 62
Table 4.2. Boundary and Computational conditions of CFD 71
Table 4.3. Grid quality range by skewness 75
Table 4.4. Grid quality range by orthogonal quality 75
Table 5.1. Hydrogen stagnation region and HMF according to leakage position(A=177.7°) 82
Table 5.2. Hydrogen stagnation region and HMF according to leakage position(A=150°) 85
Table 5.3. Hydrogen stagnation region and HMF according to leakage position(A=120°) 92
Table 5.4. Average HMF of hydrogen tank storage room according to leakage point and air inlet position(A=177.7°) 98
Table 5.5. Average HMF of hydrogen tank storage room according to leakage point and air inlet position(120°) 102
Table 5.6. Average HMF of hydrogen tank storage room according to leakage point and vent position(177.7°) 109
Table 5.7. Average HMF of hydrogen tank storage room according to leakage point and vent position(120°) 114
Table 5.8. In Case I~ CaseVI, the position of the air inlet/vent with the best ventilation performance(120°) 121
Table 5.9. In Case I~ Case VI, the position of the air inlet/vent with the best ventilation performance(177.7°) 121
Table 5.10. Position of the air inlet/vent with the best ventilation performance according to the ceil angle(A) 121
Table 6.1. Ventilation capacity according to Air Inlet velocity 122
Table 6.2. Average velocity according to leakage point, Air Inlet and Vent position(177.7°) 133
Table 6.3. Average velocity according to leakage point, Air Inlet and Vent position(120°) 134
Table 6.4. Average HMF of leaked hydrogen by ventilation method, leakage point and position of air inlet/vent(177.7°) 144
Table 6.5. Average HMF of leaked hydrogen by ventilation method, leakage point and position of air inlet/vent(120°) 148
Fig. 1.1. General arrangement of IPA's econuri ship 32
Fig. 2.1. Scheme of hydrogen fuel cell ship 39
Fig. 3.1. LNG storage tank at E-ship 45
Fig. 3.2. Geometry of hydrogen tank 46
Fig. 3.3. Geometry of hydrogen tank storage room according to A 49
Fig. 3.4. Flowchart of general numerical solution algorithm 52
Fig. 4.1. Release chamber scheme and position of sensors 62
Fig. 4.2. Comparisons of the calculated H₂ molar fraction by CFD and the experimental data at locations 1, 4, 6 and 7 64
Fig. 4.3. Calculated instantaneous snapshots at different time instants(from top left: 10 s, 50 s, 100 s, 150 s, 240 s and 500 s) 66
Fig. 4.4. Calculated instantaneous snapshots of hydrogen molar fraction by CFX at different time instants(10 s, 50 s, 100 s, 150 s, 240 s and 500 s) 67
Fig. 4.5. Leakage position on the hydrogen tank 68
Fig. 4.6. Position of Air inlet and Vent 72
Fig. 4.7. Average velocity in hydrogen tank storage room by mesh 77
Fig. 4.8. Mesh in hydrogen tank storage room 78
Fig. 4.9. Cross sectional view of grid created in hydrogen tank storage room 78
Fig. 5.1. Scheme diagram of the hydrogen tank storage room with a ceil angle(A) of 177.7° and the position of the hydrogen sensors. 80
Fig. 5.2. The leakage scene according to the leakage position 81
Fig. 5.3. Mole fraction of leaked hydrogen in the hydrogen tank storage room by Case 84
Fig. 5.4. Contours of HMF in hydrogen tank storage room(transverse) 87
Fig. 5.5. HMF of S0~S9 in CaseI 89
Fig. 5.6. HMF of S10~S19 in Case II 89
Fig. 5.7. HMF of S20~S29 in Case III 89
Fig. 5.8. Contours of HMF by Case when the ceil angle is 120°(longitudinal) 91
Fig. 5.9. Contours of HMF according to the ceil angle in Case I(transverse) 94
Fig. 5.10. Position of air inlet at fixed Vent 97
Fig. 5.11. Inlet air streamline according to the location of the air inlet in Case III 100
Fig. 5.12. Streamlines of leaked hydrogen and hydrogen mole fraction in Case II(A=120°) 103
Fig. 5.13. Streamlines of leaked hydrogen and hydrogen mole fraction in Case V(A=120°) 105
Fig. 5.14. Comparison of the average HMF of leaked hydrogen by air inlet position(A=120° and 177.7°) 106
Fig. 5.15. Position Vent in fixed air inlet 108
Fig. 5.16. Average HMF of leaked hydrogen by vent position(A=177.7°) 110
Fig. 5.17. Streamlines of leaked hydrogen and velocity distribution of inlet air in Case III(A=177.7°) 112
Fig. 5.18. Contours of average HMF in Case III when the ceil angle is 120°(longitudinal) 115
Fig. 5.19. In case of Vent-1 and Vent-2, the average HMF of leaked hydrogen according to the height in Case III(A=120°) 116
Fig. 5.20. HMF distribution of leaked hydrogen in the hydrogen tank storage room in Case IV(A=120°) 118
Fig. 5.21. Comparison of the average HMF of leaked hydrogen in vent on opposite sidewalls(A=120°) 119
Fig. 6.1. Average HMF of leaked hydrogen according to ventilation volume(A=177.7°) 125
Fig. 6.2. In Case V, HMF in the hydrogen tank storage room according to ventilation volume(A=177.7°) 127
Fig. 6.3. In Case II / Inlet-1 / Vent-1 and Case V, HMF in the hydrogen tank storage room according to ventilation volume(A=120°) 129
Fig. 6.4. In Case V, HMF in the hydrogen tank storage room according to ventilation volume(A=120°) 131
Fig. 6.5. In Case V, Inlet-1 / Vent-1, HMF in the hydrogen tank storage room according to ventilation volume(A=120°) 132
Fig. 6.6. In Case V, horizontal velocity distribution in the hydrogen tank storage room according to the ventilation volume(A=177.7°) 136
Fig. 6.7. In Case VI / Inlet-2, horizontal velocity distribution according to the ventilation volume(A=177.7°) 137
Fig. 6.8. In Case V, horizontal velocity distribution according to the ventilation volume(A=120°) 139
Fig. 6.9. In Case II / Inlet-1 / Vent-1, horizontal velocity distribution according to the ventilation volume(A=120°) 141
Fig. 6.10. Types of ventilation systems 143
Fig. 6.11. In Case III, HMF in the hydrogen tank storage room according to the ventilation method(A=177.7°) 145
Fig. 6.12. In Case III, distribution of HMF in the hydrogen tank storage room according to the ventilation method(A=177.7°) 147
Fig. 6.13. In Case III / Inlet-1 / Vent-2, velocity contour at the sidewall of the Vent by ventilation method(A=120°) 150
Fig. 6.14. In Case III / Inlet-1 / Vent-2, mean pressure at the sidewall of the Vent by ventilation method(A=120°) 151
Fig. 6.15. In Case II / Inlet-1 / Vent-1, pressure contour at the sidewall of the Vent by ventilation method(A=120°) 153