표제지
목차
Nomenclature 6
요약 11
Abstract 13
1. 서론 15
2. 선행 연구 19
2.1. 임계열유속 예측 모델 19
2.2. 열전달 모델 22
2.3. 해양환경에서의 열수력 실험 연구 25
3. 실험장치 및 방법 32
3.1. 시편 제작 방법 32
3.2. 상하요동 플랫폼 32
3.3. 수조비등 실험 방법 34
3.3.1. 수조비등 실험 장치 34
3.3.2. 수조비등 실험 방법 35
3.3.3. 불확실성 분석 36
4. 실험 결과 및 고찰 43
4.1. 정지조건에서 수조비등 실험결과 43
4.2. 상하요동 조건에서 수조비등 실험결과 44
4.2.1. 진폭 변화에 따른 실험결과 44
4.2.2. 주기 변화에 따른 실험결과 45
4.3. 임계열유속 감소 경향 46
4.4. 임계열유속 감소 원인 분석 47
4.5. 열전달계수 감소 경향 및 분석 49
4.6. 향후 연구 계획 51
5. 결론 68
6. 참고문헌 70
Figure 1.1. Boiling curve 18
Figure 2.1. Vapor jet formation schematic at high heat flux. 27
Figure 2.2. Vapor structure near heated surface at high heat fluxes. 28
Figure 2.3. Schematic of processes involved in boiling and their relations to burnout. 29
Figure 2.4. CHF model based on force balance (a) Forces due to surface tension, gravity and momentum acting on a bubble parallel to the theater surface; (b) sketch... 30
Figure 2.5. Actual and idealized flow fields 31
Figure 3.1. The method of fabrication for the test samples. 38
Figure 3.2.1. Heaving platform 39
Figure 3.2.2. Heaving platform motion measured with wire sensor 40
Figure 3.3.1. The pool boiling experimental apparatus 41
Figure 3.3.2. The heaving platform operation mode 42
Figure 4.1.1. Boiling curve in static conditions with this study. 52
Figure 4.1.2. Boiling curve in static conditions with the previous research data 53
Figure 4.2.1.1. The wall temperature and platform location over time depending on variable Amplitudes (with fixed Period) 54
Figure 4.2.1.2. Location and acceleration of the platform over time 55
Figure 4.2.1.3. Boiling curve in heaving conditions depending on variable Amplitudes (with fixed Period) 56
Figure 4.2.2.1. The wall temperature and platform location over time depending on variable Periods (with fixed Amplitude) 57
Figure 4.2.2.2. Boiling curve in heaving conditions depending on variable Periods (with fixed Amplitude) 58
Figure 4.3. CHF ratio according to minimum heaving acceleration rate 59
Figure 4.4.1. (a) Schematic of vapor columns (Zuber) (b) Schematic of mushroom bubble (Haramura and Katto) 60
Figure 4.4.2. High-speed photographs of the bubble dynamics (a) platform location : bottom (b) platform location : top 62
Figure 4.5.1. Boiling curve in heaving conditions (a) Amplitude variable (b) Period variable 63
Figure 4.5.2. Heat transfer coefficient in heaving conditions (a) Amplitude variable (b) Period variable 64
Figure 4.5.3. The wall temperature and platform location over time at heat flux 900kW/m² 65
Figure 4.5.4. Growth and collapse of reversible dry spot 66
Figure 4.5.5. Schematic of the process at the reversible dry spot 67