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1.
新型沙漏式浮式生产储油系统的概念设计分析   总被引:3,自引:0,他引:3  
为了解决现有传统船型、圆柱筒型和棱柱型浮式生产储油系统(FPSO)的性能局限,提出了一种具有沙漏外形,并配有各种生产和生活功能模块的新型沙漏式FPSO.利用基于频域势流理论的边界元数值模拟和谱分析方法分析浮体在波浪中垂荡和纵摇运动性能,结合概率统计理论分析甲板上浪概率,采用变排水量法计算浮体的静稳性曲线.最后,与挪威Sevan Marine公司设计的圆筒形FPSO浮体模型和中海油公司设计的八角型FPSO浮体模型进行对比.结果表明,新型沙漏式浮体外形设计能够显著地提高FPSO的稳性和各项水动力性能,可以为深水油气开发提供一种有效的新型工程装备和解决方案.  相似文献   

2.
具有水动力性能优势的新概念沙漏型浮体,由于具有水线面面积和初稳性高较小等特性,其纵摇运动的固有频率与推进器纵向控制力的频率接近,导致浮体水平面和垂直面的运动产生耦合作用,从而引起较大的纵荡和纵摇运动响应.针对此问题,采用基于势流理论的边界元方法计算沙漏型浮体的波浪荷载和水动力参数.结合实际布置推进器产生的控制荷载,建立沙漏型浮体纵荡-垂荡-纵摇耦合运动方程.通过数值模拟和频率响应传递函数,重点讨论沙漏型浮体多自由度运动的相互影响以及推进器附加纵摇力矩引发的问题.最后,将纵摇阻尼和惯性力项加入纵荡控制力中,显著降低了纵荡和纵摇运动响应,很好地满足了定位精度的要求.  相似文献   

3.
文章采用线性波理论和特征函数展开法,推导了带沉箱圆柱形浮体的辐射和绕射速度势解析表达式,并对垂荡运动和水动力垂向分量进行了数值分析;研究表明相对较大的沉箱不仅改变了浮体垂荡运动幅值和水动力垂向分量幅值,而且改变了幅值的变化趋势;相对较小的沉箱对浮体的垂荡运动和水动力垂向分量的影响可以忽略.  相似文献   

4.
基于特征函数匹配方法,建立了两层流体中垂直圆柱浮体水波辐射问题的求解理论,导出了垂直圆柱浮体的附加质量和阻尼系数的计算公式.针对垂荡、横荡与横摇振荡运动模式,计算分析了垂直圆柱浮体的附加质量和阻尼系数特性,并与均匀流体的情况进行了比较.结果表明,在垂直圆柱浮体的某个振荡频率范围内,流体的分层效应对其附加质量和阻尼系数是有显著影响的.  相似文献   

5.
基于三维移动脉动(3DTP)源格林函数,针对安装稳定鳍的小水线面双体船(SWATH),计入两片体之间的水动力干扰、黏性和稳定鳍的影响,建立了SWATH耐波性频域计算方法.通过与SWATH试验模型(SWATH-M)的试验结果对比,验证了计算方法的可靠性,进而研究了航速对SWATH-M耐波性的影响,并分析了黏性和稳定鳍对SWATH-M整船所受水动力的贡献.结果表明,基于3DTP的船体运动计算结果与试验结果吻合良好.船体的运动响应算子随波长变化呈现出双极值.随着航速提高,短波共振区附近的运动响应算子极值增大,而长波共振区附近的运动响应算子极值降低.黏性和稳定鳍对阻尼系数的影响主要体现在垂荡-垂荡阻尼系数和纵摇-纵摇阻尼系数上,对波浪干扰力的影响主要体现在垂荡力虚部和纵摇力矩实部.  相似文献   

6.
在有限常水深、同轴同半径圆柱体沉箱条件下,基于特征函数展开法,推导了垂直放置的圆柱形浮体在水波作用下所受到流体作用力表达式.涉及了浮体做垂荡、纵荡和纵摇运动相关联的辐射势,以及在入射波的作用下由于浮体固定不动而相关联的绕射势.还推导了激励力、附加质量和阻尼系数表达式,采用同平底单浮体运动条件相比和激励力计算的两种方法的方式验证了推导的表达式.最后分析了沉箱高度对浮体运动的特有影响,在算例范围内沉箱的高度对垂荡、纵摇运动的影响较大,对纵荡运动的影响较小.  相似文献   

7.
应用三维势流理论、非线性时域动力耦合分析方法以及深海平台混合模型试验研究方法,针对我国南海北部一座15 km桁架式深吃水立柱式平台(Truss Spar),在不同海况下对作业装载的平台锚泊系统进行了截断水深模型试验、数值重构研究,并数值外推到全水深,较好地预报了其水动力性能,包括纵荡、垂荡和纵摇. 经分析:Truss Spar平台的垂荡、纵摇低频运动分量较大,同时纵荡也表现出很强的低频特性;此外,平台具有较小的垂荡运动幅值,垂荡性能较好,能较好地满足海上油气生产的要求.  相似文献   

8.
通过对张力腿平台型式、特点及发展历程的分析,提出张力腿平台型式创新及性能优化应遵循主体集中布置、延伸式系泊、最小水线面等趋势,进而提出了新型的张力腿平台概念。该新型平台主体在垂向自平衡与系泊系统分离,且具有最小化的水线面和延伸式系泊等特性。最小化的水线面的概念可以最大限度减小平台在水线面处所受环境载荷。主体垂向分离且自平衡的概念可以同时保证平台的静水回复刚度,并解除平台纵、横荡与垂荡的耦合效应,减小张力腿的“疲劳效应”。主体垂向可以在底部附加垂荡板以控制垂荡。延伸式系泊可以增加平台在纵、横摇方向上的刚度。之后本文又给出了此种平台概念设计的具体流程和要点,并概念设计了一座新型平台。  相似文献   

9.
针对深海桁架式Spar平台,考虑三点张紧式系泊定位,研究其纵荡、横荡和垂荡三个自由度的固有运动特性.考虑纤维缆索的材料非线性与几何非线性特性,对缆索力学平衡方程重新推导计算系泊缆索张力与位移的变化关系.采用准静态方法,建立考虑系泊作用的平台耦合系统纵荡、横荡和垂荡运动方程,数值求解平台固有运动特性,并讨论系泊条件对平台自振特性的影响.结果表明,在平台小幅运动下,系泊回复力与位移基本呈线性关系,但随着平台位移的增大,系泊回复力随位移变化开始表现出一定的非线性;系泊条件的改变将会改变平台水平运动的固有频率;系泊系统对垂荡运动的固有特性影响不大.  相似文献   

10.
针对大型海上浮体平台常采用分段式结构以保证平台在海浪冲击下结构的稳定性,分段式结构使得浮体平台的水动力特性变复杂的问题,通过耦合移动粒子半隐式法(MPS)与离散单元法(DEM),在全拉格朗日框架下建立了二维造波水池模型。本文比较并修正了造波模型,提高了造波的准确度,并对消波模型进行了改进,改进后的计算量下降了12.1%;对含有不同数量子平台的分段浮体平台在规则波影响下的运动进行了数值模拟,探讨了分段浮体平台运动时子平台间的动态关系。研究结果表明,子平台位置靠近整体平台下游时,其垂荡和纵摇响应逐渐衰减,纵荡响应成为主导特征。大型分段浮体平台在设计时需注意减小前部子平台的垂荡和纵摇,并增加连接部件对尾部子平台的约束力,防止尾部子平台相互碰撞或脱离主浮体平台。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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