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포화상태에 놓인 C-Type 액체수소 탱크의 슬로싱이 열 유속과 BOG에 미치는 변화의 수치적 분석

Numerical Study of Heat Flux and BOG in C-Type Liquefied Hydrogen Tank under Sloshing Excitation at the Saturated State

  • 이진호 (인하대학교 조선해양공학과) ;
  • 황세윤 (인하대학교 조선해양공학과) ;
  • 이성제 (인하대학교 조선해양공학과) ;
  • 이장현 (인하대학교 조선해양공학과)
  • Lee, Jin-Ho (Department of Naval Architecture and Ocean Engineering, Inha University) ;
  • Hwang, Se-Yun (Department of Naval Architecture and Ocean Engineering, Inha University) ;
  • Lee, Sung-Je (Department of Naval Architecture and Ocean Engineering, Inha University) ;
  • Lee, Jang Hyun (Department of Naval Architecture and Ocean Engineering, Inha University)
  • 투고 : 2022.06.28
  • 심사 : 2022.09.30
  • 발행 : 2022.10.31

초록

본 논문은 슬로싱 상태에 놓인 포화 상태 액체수소탱크에서 열 유속 및 BOG(Boil-off gas)의 경향을 다루고 있다. 특히, 액체-기체간의 침투 및 혼합에 의한 열 교환에 관심을 두었다. 먼저, VOF(Volume of fluid)와 Eulerian 기반의 다상 유동모델로 모형 슬로싱 실험을 모사하여 압력을 예측하고 계측된 값과 비교하였다. 자유 수면 및 충격 압력 실험 결과와 해석 결과를 비교하였으며, 유체의 속도 예측에서 정확할 수 있음을 간접적으로 증명하였다. 그리고 2차원의 Type-C 원통형 수소탱크를 대상으로 다상열유동해석을 수행하였다. 이때 포화상태에 놓인 액체 및 기체수소를 가정하고, 해석을 통해 각 상간의 혼합에 의한 열 교환의 수준을 확인하고자 하였다. 단, 상간의 열 교환만을 관심으로 두고 있었으므로 질량전달 및 기화모델은 해석에서 제외하였다. 최종적으로 상의 혼합으로 인해 액체수소로 유입되는 열 유속의 기여도에 대하여 정리하였다. 또한 액체수소로 유입되는 열 유속과 집중 질량 기반의 간이식을 통해 BOG 발생량 및 경향을 예측하고 분석하였다.

This study was conducted to predict the tendency for heat exchange and boil-off gas (BOG) in a liquefied hydrogen tank under sloshing excitation. First, athe fluid domain excited by sloshing was modeled using a multiphase-thermal flow domain in which liquid hydrogen and hydrogen gas are in the saturated state. Both the the volume of fluid (VOF) and Eulerian-based multi-phase flow methods were applied to validate the accuracy of the pressure prediction. Second, it was indirectly shown that the fluid velocity prediction could be accurate by comparing the free surface and impact pressure from the computational fluid dynamics with those from the experimental results. Thereafter, the heat ingress from the external convective heat flux was reflected on the outer surfaces of the hydrogen tank. Eulerian-based multiphase-heat flow analysis was performed for a two-dimensional Type-C cylindrical hydrogen tank under rotational sloshing motion, and an inflation technique was applied to transform the fluid domain into a computational grid model. The heat exchange and heat flux in the hydrogen liquid-gas mixture were calculated throughout the analysis,, whereas the mass transfer and vaporization models were excluded to account for the pure heat exchange between the liquid and gas in the saturated state. In addition, forced convective heat transfer by sloshing on the inner wall of the tank was not reflected so that the heat exchange in the multiphase flow of liquid and gas could only be considered. Finally, the effect of sloshing on the amount of heat exchange between liquid and gas hydrogen was discussed. Considering the heat ingress into liquid hydrogen according to the presence/absence of a sloshing excitation, the amount of heat flux and BOG were discussed for each filling ratio.

키워드

과제정보

본 논문은 산업통상자원부 조선해양산업핵심기술개발 사업 선박용 액체수소 탱크의 열손실 최소화 핵심기술 개발(20013102)'의 지원으로 수행한 연구이며, 본 논문의 참여학생은 2022년도 정부(산업통상자원부)의 재원으로 한국산업기술진흥원의 지원(P0001968, 친환경·스마트 선박 R&D 전문인력양성사업)을 받았습니다.

참고문헌

  1. Adom, E., Islam, S.Z., Ji, X. (2010) Modelling of Boil-off Gas in LNG Tanks: A Case Study, Int. J. Eng. & Technol., 2, pp.292-296.
  2. Alkhaledi, A.N., Sampath, S., Pilidis, P. (2021) A Hydrogen Fuelled LH2 Tanker Ship Design, Ships & Offshore Struct., pp.1-10.
  3. Ansys Inc. (2020) Fluent Theory Guide Release 2020, Ansys. Inc.
  4. Bae, S.W., Jeong, J.J., Chang, S.K., Cho, H.K. (2007) Two Phase Flow Models and Numerical Methods of the Commercial CFD Codes, Korea Atomic Energy Research Institute, Korea, pp.16-36.
  5. Baker, C.R., Shaner, R.L. (1978) A Study of the Efficiency of Hydrogen Liquefaction, Int. J. Hydrog. Energy, 3(3), pp. 321334.
  6. Chandran, P., Venugopal, G., Jaleel, H.A., Rajkumar, M.R. (2017) Laminar Forced Convection from a Rotating Horizontal Cylinder in Cross Flow, J. Therm. Sci., 26(2), pp.153-159. https://doi.org/10.1007/s11630-017-0924-9
  7. Ferrin, J.L., Perez-Perez, L.J. (2020) Numerical Simulation of Natural Convection and Boil-off in a Small Size Pressurized LNG Storage Tank, Comput. & Chem. Eng., 138, 106840. https://doi.org/10.1016/j.compchemeng.2020.106840
  8. Han, W.H., Choi, J.S., Choi, J.H. (2010) The Trends of Hydrogen Energy Technology Development and Application to Ship, J. Korean Soc. Mar. Environ. & Safety, 16, pp.313-320.
  9. Hwang, S.Y., Lee, J.H. (2016) Comparative Study on the Thermal Insulation of Membrane LNG CCS by Heat Transfer Analysis, J. Comput. Struct. Eng. Inst. Korea, 29(1), pp.53-60. https://doi.org/10.7734/COSEIK.2016.29.1.53
  10. Hwang, S.Y., Lee, J.H. (2021) The Numerical Investigation of Structural Strength Assessment of LNG CCS by Sloshing Impacts Based on Multiphase Fluid Model, Appl. Sci., 11(16), 7414. https://doi.org/10.3390/app11167414
  11. Jeon, G.M., Park, J.C., Choi, S. (2021) Multiphase-Thermal Simulation on BOG/BOR Estimation due to Phase Change in Cryogenic Liquid Storage Tanks, Appl. Therm. Eng., 184, 116264. https://doi.org/10.1016/j.applthermaleng.2020.116264
  12. Kang, D.H., Lee, Y.B. (2005) Summary Report of Sloshing Model Test for Rectangular Model No.001, Daewoo Shipbuilding and Marine Engineering Company, Korea, pp.2-7.
  13. Li, F., Yuan, Y., Yan, X., Malekian, R., Li, Z. (2018) A Study on a Numerical Simulation of the Leakage and Diffusion of Hydrogen in a Fuel Cell Ship, Renew. & Sustain. Energy Rev., 97, pp.177-185. https://doi.org/10.1016/j.rser.2018.08.034
  14. Lin, Y., Ye, C ., Yu, Y.Y., Bi, S.W. (2018) An Approach to Estimating the Boil-off Rate of LNG in Type C Independent Tank for Floating Storage and Regasification Unit under Different Filling Ratio, Appl. Therm. Eng., 135, pp.463-471. https://doi.org/10.1016/j.applthermaleng.2018.02.066
  15. Liu, Z., Feng, Y., Yan, J., Li, Y., C hen, L. (2020) Dynamic Variation of Interface Shape in a Liquid Oxygen Tank under a Sinusoidal Sloshing Excitation, Ocean Eng., 213, 107637. https://doi.org/10.1016/j.oceaneng.2020.107637
  16. Mao, X., Ying, R., Yuan, Y., Li, F., Shen, B. (2021) Simulation and Analysis of Hydrogen Leakage and Explosion behaviors in Various Compartments on a Hydrogen Fuel Cell Ship, Int. J. Hydrog. Energy, 46, pp.6857-6872. https://doi.org/10.1016/j.ijhydene.2020.11.158
  17. Park, S.H., Kim, B.J. (2020) Comparative Study of Two-Fluid and VOF Methods for Sloshing Flows, Trans. Korean Soc. Mech. Eng., 44(12), pp.711-716. https://doi.org/10.3795/KSME-B.2020.44.12.711
  18. Saleem, A., Farooq, S., Karimi, I.A., Banerjee, R. (2018) A CFD Simulation Study of Boiling Mechanism and BOG Generation in a Full-Scale LNG Storage Tank, Comput. & Chem. Eng., 115, pp.112-120. https://doi.org/10.1016/j.compchemeng.2018.04.003
  19. Scheufler, H., Gerstmann, J. (2022) Heat and Mass Transfer in a Cryogenic Tank in Case of Active-Pressurization, Cryog., 121, 103391. https://doi.org/10.1016/j.cryogenics.2021.103391
  20. Smith, J.R., Gkantonas, S., Mastorakos, E. (2022) Modelling of Boil-off and Sloshing Relevant to Future Liquid Hydrogen Carriers, Energies, 15(6), 2046. https://doi.org/10.3390/en15062046
  21. Syed, M.T., Sherif, S.A., Veziroglu, T.N., Sheffield, J.W. (1998) An Economic Analysis of three Hydrogen Liquefaction Systems, Int. J. Hydrog. Energy, 23(7), pp.565-576. https://doi.org/10.1016/S0360-3199(97)00101-8
  22. Tani, K., Himeno, T., Watanabe, T., Kobayashi, H., Toge, T., Unno, S, Kamiya, S., Muragishi, O., Kanbe, K. (2021) CFD Simulation of Pressure Reduction inside Large-Scale Liquefied Hydrogen Tank, Int. Conf. Hydrogen Safety.
  23. Vishnu, S.B., Kuzhiveli, B.T. (2022) Mathematical Modeling of Thermal Stratification in a Double Wall Cryogenic Propellant Tank With Different Insulations using One-Dimensional Flow over Vertical Plate Approximation, Cryogenics, 121, 103393. https://doi.org/10.1016/j.cryogenics.2021.103393
  24. Wu, S., Ju, Y. (2021). Numerical Study of the Boil-off Gas(BOG) Generation Characteristics in a Type C Independent Liquefied Natural Gas (LNG) Tank under Sloshing Excitation, Energy, 223, 120001. https://doi.org/10.1016/j.energy.2021.120001
  25. Yu, K., Ge, Z., Korpus, R. (2016) CFD Predictions of FLNG BOG Including the Influence of Filling, Offloading, and Vessel Motion, In Offshore Technology Conference.
  26. Zakaria, M.S., Osman, K., Saadun, M.N.A., Manaf, M.Z.A., Mohd Hanafi, M.H. (2013) Computational Simulation of Boil-off Gas Formation inside Liquefied Natural Gas Tank using Evaporation Model in Ansys Fluent, Appl. Mech. & Mater., 393, pp.839-844. https://doi.org/10.4028/www.scientific.net/AMM.393.839