浮式液化天然气生产储卸装置(floating liquefied natural gas system,FLNG)特种液货船作为开发海上天然气田的新式装置,极大的方便了对处于深海的气田的开发利用,该文以“Prelude”号FLNG作为母船,提出一种新型FLNG低温能量管理系统。...浮式液化天然气生产储卸装置(floating liquefied natural gas system,FLNG)特种液货船作为开发海上天然气田的新式装置,极大的方便了对处于深海的气田的开发利用,该文以“Prelude”号FLNG作为母船,提出一种新型FLNG低温能量管理系统。该系统主要利用液态空气作为媒介储存和释放能量,通过液态空气冷能与混合制冷循环相结合实现天然气液化过程,在提高LNG生产性能的同时集成了CO_(2)液化循环和电力的生产,通过CO_(2)液化和剩余冷能发电提高系统的输出性能,实现了FLNG船舶冷能的多级利用,也为FLNG船舶冷能利用提供新方法,新途径。所提系统相较于基准模型具有更好的性能,在7.04年可实现成本回收。最后采用多目标性能优化,进一步提高系统㶲效率达60.67%,同时降低约2.3%的成本。该FLNG低温能量管理系统有高效、低耗、稳收益、低碳化等特点,可更好优化海上LNG供应链,促进航运业“双碳”发展。展开更多
Strong hydrodynamic interactions during the side-by-side offloading operation between floating liquefied natural gas(FLNG) and liquefied natural gas carrier(LNGC) can induce high risks of collision. The weather vane e...Strong hydrodynamic interactions during the side-by-side offloading operation between floating liquefied natural gas(FLNG) and liquefied natural gas carrier(LNGC) can induce high risks of collision. The weather vane effect of a single-point mooring system normally results in the satisfactory hydrodynamic performance of the side-by-side configuration in head seas. Nevertheless, the changes in wave directions in real sea conditions can significantly influence the relative motions. This article studies the relative motions of the side-by-side system by using the theoretical analysis method and the numerical calculation method. Based on the three-dimensional potential theory modified by artificial damping-lid method, the frequency-domain hydrodynamic coefficients can be improved to calculate the retardation functions for the multi-body problem. An in-house code is then developed to perform the time-domain simulation of two vessels, through which the relative motions are subsequently obtained. A range of oblique waves are chosen for the extensive calculation of relative motions between the two vessels, which are further analyzed in terms of the phase shift of motion responses induced by specific resonant wave patterns. Investigation results show that wave directions have a significant influence on the relative sway, roll, and yaw motions. Under the circumstance that the absolute phase shift between the roll motions of two vessels approaches 180°, stronger relative motions are induced when LNGC is on the weather side.Moreover, the gap water resonances at high frequencies tend to cause the dangerous opposed oscillation of two vessels in the sway and yaw modes, whereas FLNG reduces the gap water resonances and relative motions when located on the weather side.展开更多
The Floating Liquefied Natural Gas （FLNG） is a new type of floating platform for the exploitation of stranded offshore oil/gas fields. The side by side configuration for the FLNG vessel and the LNG carrier arranged ...The Floating Liquefied Natural Gas （FLNG） is a new type of floating platform for the exploitation of stranded offshore oil/gas fields. The side by side configuration for the FLNG vessel and the LNG carrier arranged in parallel is one of the possible choices for the LNG offloading. During the offloading operations, the multiple floating bodies would have very complex responses due to their hydrodynamic interactions. In this study, numerical simulations of multiple floating bodies in close proximity in the side by side offloading configuration are carried out with the time domain coupled analysis code SIMO. Hydrodynamic interactions between the floating bodies and the mechanical coupling effects between the floating bodies and their connection systems are included in the coupled analysis model. To clarify the hydrodynamic effects of the two vessels, numerical simulations under the same environmental condition are also conducted without considering the hydrodynamic interactions, for comparison. It is shown that the hydrodynamic interactions play an important role in the low frequency motion responses of the two vessels, but have little effect on the wave frequency motion responses. In addition, the comparison results also show that the hydrodynamic interactions can affect the loads on the connection systems.展开更多
国内浮式天然气液化装置(Floating Liquid Natural Gas unit,FLNG)装备技术水平尚处于初步阶段,缺乏一体化设计团队,若全部依靠进口技术装备则投资过高,项目经济性难以保证。FLNG在南海恶劣海况条件下服役,其浮式生产装备技术面临新的...国内浮式天然气液化装置(Floating Liquid Natural Gas unit,FLNG)装备技术水平尚处于初步阶段,缺乏一体化设计团队,若全部依靠进口技术装备则投资过高,项目经济性难以保证。FLNG在南海恶劣海况条件下服役,其浮式生产装备技术面临新的挑战。对于以上问题,提出:采用国内自主知识产权的浮式液化技术,建设一流的设计队伍;集中优势力量强强联合,打造国内一体化的FLNG建造团队;理论研究与实验论证相结合,开发适合海上工况的浮式液化关键设备,提高设备国产化程度。展开更多
The present research focuses on experimentally clarifying the effect of inner-tank sloshing on the hydrodynamics of an Floating Liquefied Natural Gas（FLNG）system.Through the comparisons of the results obtained from ...The present research focuses on experimentally clarifying the effect of inner-tank sloshing on the hydrodynamics of an Floating Liquefied Natural Gas（FLNG）system.Through the comparisons of the results obtained from the model tests carried out with the vessel model ballasted with liquid and solid cargo separately,the effects of the inner-tank sloshing on the hydrodynamics of an FLNG system are highlighted and presented.Statistical languages of the maximum,minimum,mean values and the standard deviations and power density spectra calculated with the help of the algorithm of Fast Fourier Transformation（FFT）are provided.It is concluded that the effects of the inner-tank sloshing on the responses of the FLNG system are sensitive to wave excitation frequencies,and that the effects of the inner-tank sloshing play an important role,particularly in the roll motion of the FLNG hull.The outcome of the proposed technique would offer constructive feedback,which can lead to more practical applications and can serve as a reference for the verification of the potential numerical simulations by other researchers.展开更多
Motion responses of the floating liquefied natural gas(FLNG)hull and the mooring loads in a 100-year return environmental condition are predicted with the help of the well known coupled dynamic analysis code DeepC.A s...Motion responses of the floating liquefied natural gas(FLNG)hull and the mooring loads in a 100-year return environmental condition are predicted with the help of the well known coupled dynamic analysis code DeepC.A ship-shaped turret-moored FLNG moored by 4×3 chain-polyester-chain lines in 1.5 km depth of water is studied.Two types of turrets such as internal and external turrets,resulting from diferent locations of the turrets,are adopted respectively in the numerical simulations.Motion responses of the FLNG hull and forces of the mooring lines obtained from the internal turret case and external turret case are compared with each other.Significant diferences are obtained.Statistic analysis is also used to analyze the comparison results,and efects of the turret location on the FLNG hydrodynamic characteristics are summed up.The conclusion regarding the hydrodynamic diferences between internal and external turret-moored FLNG systems would provide help for design of the FLNG system.展开更多
文摘浮式液化天然气生产储卸装置(floating liquefied natural gas system,FLNG)特种液货船作为开发海上天然气田的新式装置,极大的方便了对处于深海的气田的开发利用,该文以“Prelude”号FLNG作为母船,提出一种新型FLNG低温能量管理系统。该系统主要利用液态空气作为媒介储存和释放能量,通过液态空气冷能与混合制冷循环相结合实现天然气液化过程,在提高LNG生产性能的同时集成了CO_(2)液化循环和电力的生产,通过CO_(2)液化和剩余冷能发电提高系统的输出性能,实现了FLNG船舶冷能的多级利用,也为FLNG船舶冷能利用提供新方法,新途径。所提系统相较于基准模型具有更好的性能,在7.04年可实现成本回收。最后采用多目标性能优化,进一步提高系统㶲效率达60.67%,同时降低约2.3%的成本。该FLNG低温能量管理系统有高效、低耗、稳收益、低碳化等特点,可更好优化海上LNG供应链,促进航运业“双碳”发展。
基金supported by the China National Scientific and Technology Major Project(2016ZX05028-002-004)
文摘Strong hydrodynamic interactions during the side-by-side offloading operation between floating liquefied natural gas(FLNG) and liquefied natural gas carrier(LNGC) can induce high risks of collision. The weather vane effect of a single-point mooring system normally results in the satisfactory hydrodynamic performance of the side-by-side configuration in head seas. Nevertheless, the changes in wave directions in real sea conditions can significantly influence the relative motions. This article studies the relative motions of the side-by-side system by using the theoretical analysis method and the numerical calculation method. Based on the three-dimensional potential theory modified by artificial damping-lid method, the frequency-domain hydrodynamic coefficients can be improved to calculate the retardation functions for the multi-body problem. An in-house code is then developed to perform the time-domain simulation of two vessels, through which the relative motions are subsequently obtained. A range of oblique waves are chosen for the extensive calculation of relative motions between the two vessels, which are further analyzed in terms of the phase shift of motion responses induced by specific resonant wave patterns. Investigation results show that wave directions have a significant influence on the relative sway, roll, and yaw motions. Under the circumstance that the absolute phase shift between the roll motions of two vessels approaches 180°, stronger relative motions are induced when LNGC is on the weather side.Moreover, the gap water resonances at high frequencies tend to cause the dangerous opposed oscillation of two vessels in the sway and yaw modes, whereas FLNG reduces the gap water resonances and relative motions when located on the weather side.
基金supported by the China National Scientific and Technology Major Project(Grant No.2011ZX05026-006-05)the Science Foundation of Science and Technology Commission of Shanghai Municipality (Grant No.11ZR1417800)supported by the Lloyds Register Educational Trust (LRET) to the Joint Centre Involving University Coollege London,Shanghai Jiao Tong University and Harbin Engineering University
文摘The Floating Liquefied Natural Gas （FLNG） is a new type of floating platform for the exploitation of stranded offshore oil/gas fields. The side by side configuration for the FLNG vessel and the LNG carrier arranged in parallel is one of the possible choices for the LNG offloading. During the offloading operations, the multiple floating bodies would have very complex responses due to their hydrodynamic interactions. In this study, numerical simulations of multiple floating bodies in close proximity in the side by side offloading configuration are carried out with the time domain coupled analysis code SIMO. Hydrodynamic interactions between the floating bodies and the mechanical coupling effects between the floating bodies and their connection systems are included in the coupled analysis model. To clarify the hydrodynamic effects of the two vessels, numerical simulations under the same environmental condition are also conducted without considering the hydrodynamic interactions, for comparison. It is shown that the hydrodynamic interactions play an important role in the low frequency motion responses of the two vessels, but have little effect on the wave frequency motion responses. In addition, the comparison results also show that the hydrodynamic interactions can affect the loads on the connection systems.
文摘国内浮式天然气液化装置(Floating Liquid Natural Gas unit,FLNG)装备技术水平尚处于初步阶段,缺乏一体化设计团队,若全部依靠进口技术装备则投资过高,项目经济性难以保证。FLNG在南海恶劣海况条件下服役,其浮式生产装备技术面临新的挑战。对于以上问题,提出:采用国内自主知识产权的浮式液化技术,建设一流的设计队伍;集中优势力量强强联合,打造国内一体化的FLNG建造团队;理论研究与实验论证相结合,开发适合海上工况的浮式液化关键设备,提高设备国产化程度。
基金supported by the Science Foundation of Science and Technology Commission of Shanghai Municipality(Grant No.11ZR1417800)the China National Scientific and Technology Major Project(Grant No.2011ZX05026-006-05)supported by also the Lloyds Register Educational Trust(LRET)to the joint centre involving University College London,Shanghai Jiao Tong University and Harbin Engineering University
文摘The present research focuses on experimentally clarifying the effect of inner-tank sloshing on the hydrodynamics of an Floating Liquefied Natural Gas（FLNG）system.Through the comparisons of the results obtained from the model tests carried out with the vessel model ballasted with liquid and solid cargo separately,the effects of the inner-tank sloshing on the hydrodynamics of an FLNG system are highlighted and presented.Statistical languages of the maximum,minimum,mean values and the standard deviations and power density spectra calculated with the help of the algorithm of Fast Fourier Transformation（FFT）are provided.It is concluded that the effects of the inner-tank sloshing on the responses of the FLNG system are sensitive to wave excitation frequencies,and that the effects of the inner-tank sloshing play an important role,particularly in the roll motion of the FLNG hull.The outcome of the proposed technique would offer constructive feedback,which can lead to more practical applications and can serve as a reference for the verification of the potential numerical simulations by other researchers.
基金the China National Significant Science&Technology Research Program(No.2008ZX05026-006)
文摘Motion responses of the floating liquefied natural gas(FLNG)hull and the mooring loads in a 100-year return environmental condition are predicted with the help of the well known coupled dynamic analysis code DeepC.A ship-shaped turret-moored FLNG moored by 4×3 chain-polyester-chain lines in 1.5 km depth of water is studied.Two types of turrets such as internal and external turrets,resulting from diferent locations of the turrets,are adopted respectively in the numerical simulations.Motion responses of the FLNG hull and forces of the mooring lines obtained from the internal turret case and external turret case are compared with each other.Significant diferences are obtained.Statistic analysis is also used to analyze the comparison results,and efects of the turret location on the FLNG hydrodynamic characteristics are summed up.The conclusion regarding the hydrodynamic diferences between internal and external turret-moored FLNG systems would provide help for design of the FLNG system.
