A Finite Element Solution of Wave Forces on Submerged Horizontal Circular Cylinders   总被引：2，自引：0，他引：2  

赵明  滕斌  谭丽 《中国海洋工程》2004,18(3):335-346

In this paper, a numerical model is established for estimating the wave forces on a submerged horizontal circular cylinder. For predicting the wave motion, a set of two-dimensional Navier-Stokes equations is solved numerically with a finite element method. In order to track the moving non-linear wave surface boundary, the Navier-Stokes equations are discretized in a moving mesh system. After each computational time step, the mesh is modified according to the changed wave surface boundary. In order to stabilize the numerical procedure, a three-step finite element method is applied in the time integration. The water sloshing in a tank and wave propagation over a submerged bar are simulated for the first time to validate the present model. The computational results agree well with the analytical solution and the experimental data.Finally, the model is applied to the simulation of interaction between waves and a submerged horizontal circular cylinder.The effects of the KC number and the cylinder depth on the wave forces are studied.  相似文献   

Simulation and Analysis of a Gravity Cyh''''nder''''s Stability in Short-Crested Sea     

Yu Ke  Su Weidong Postgraduate  River  Harbour Department  Nanjing Hydraulic ResearchInstitute  Nanjing Engineer  River  Harbour Department  Nanjing Hydraulic Research Institute  Nanjing 《中国海洋工程》1992,(1)

Generally, the reliability of ami -sliding and anti-overturning stability of an isolated gravity cylinder in a certain working period can be evaluated only when the statistical properties of short term stability are given first. The authors used numerical method to simulate the stability state function of a cylinder in short-crested sea, and further to get the probabilitical characteristics of the structure's stability by time domain analysis. The external loads appeared in the state functions include horizontal wave force, lift force and the respective moments, and the loads are correlated by co- spectrum. The numerical method presented in this paper can be used not only to solve short term reliability problem directly, but to calculate and analyse the long term reliability problem as well. For circular cylinders, an example of simulation and analysis is displayed in this paper.  相似文献   

Experimental study on stability of sunken large diameter cylindrical structure on sandy seabed during construction period     

Qin Chongren  Pang Hongli  Li Shisen  Zhang Wei 《海洋学报(英文版)》2002,21(4):581-595

ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｌａｒｇｅｄｉａｍｅｔｅｒｃｙｌｉｎｄｒｉｃａｌｓｔｒｕｃｔｕｒｅｉｓｏｆｔｅｎｕｓｅｄａｓｔｈｅｗｈａｒｆａｎｄｔｈｅｂｒｅａｋｗａｔｅｒｓｔｒｕｃｔｕｒｅｏｆｈａｒｂｏｒ.Ｓｉｎｃｅｉｔｔａｋｅｓｓｏｍｅｔｉｍｅｔｏｆｉｌｌｍａｔｅｒｉａｌｉｎｔｏｔｈｅｃｙｌｉｎｄｅｒａｆｔｅｒｔｈｅｃｙｌｉｎｄｅｒｓｈｅｌｌｉｓｓｕｎｋｅｎｔｏｔｈｅｓｅａｂｅｄ ,ｔｈｅｓｔａｂｉｌｉｔｙｏｆｔｈｅｃｙｌｉｎｄｅｒｂｅｃｏｍｅｓｃｏｎｔｒｏｌｃｏｎｄｉｔｉｏｎｆｏｒｔｈｅｓａｆ…  相似文献   

直立椭圆柱体重力场的谱分析及其应用   总被引：1，自引：0，他引：1  

范守志 《海洋与湖沼》1995,26(3):234-240

利用傅里叶积分变换法导出了埋藏的直立椭圆柱体的重力场在频率域中的解析公式，依此得了确定此直立椭圆柱体尺寸的公式，提出依据这些重力公式来计算侵入大洋地壳中的地幔柱的尺寸和洋壳厚度的方法。  相似文献   

波浪作用下软基上沉入式大直径圆筒结构的变位计算模型     

刘振纹  秦崇仁 《海洋技术学报》2005,24(1):90-94

文章通过所建立的软粘土地基土体的循环累积变位分析模型，对大直径圆筒原型结构在波浪引起的水平向循环荷载作用下的基础稳定性进行研究，计算分析了简体随循环次数的变位状况和临界稳定状态时简体所受到的土压力分布以及临界稳定状态的判别参数c值。  相似文献   

浅水破碎波对直立圆柱作用力的试验研究   总被引：2，自引：0，他引：2  

李炎保 《海洋与湖沼》1992,23(6):635-641

分析了桩柱破波力的构成特性,认为破碎波与桩柱作用过程中在不完全绕流区将出现由于附连质量迅速变化引起的冲击力和柱前后波面高度差引起的附加压差力;影响破碎波对直立圆柱作用力的因素应该包括确定破波特性的水底坡度i、入射深水波陡H_0/L_0及代表圆柱对破波作用影响的相对柱径D/H_0。通过从i=1/100到1/15五种底坡上桩柱破波力的系统试验,探索了桩柱破波力的作用特性,归纳了计算桩柱破波力的经验公式。  相似文献   

翡翠贻贝足丝器的组织结构观察     

石琼  陈舜华 《热带海洋学报》1996,(2)

用光镜和电镜技术初步探讨了翡翠贻贝Ｐｅｒｎａｖｉｒｉｄｉｓ足丝器（Ｂｙｓｓａｌａｐｐｒａｔｕｓ）的三大组成部分之间的空间结构关系，着重观察足丝柄部发生器（ＢＳＧ）的片层结构，揭示小片具有典型的胶原原纤维电镜特征。此外，通过足丝丝部的表面结构观察，发现可用众多的突起来解释足丝表面对放射性碘的强机械吸附作用；利用足丝丝部横切片，计算出其长径约１０５μｍ，短径约４０μｍ。  相似文献   

在波浪荷载作用下插入式大圆筒结构稳定性分析评述     

王晖  王乐芹  周锡礽  孙克俐 《海洋技术学报》2005,24(1):108-112

结合某大圆筒结构工程，对大圆筒结构稳定性分析中的各种计算方法进行了综合评述与讨论，尤其对大圆筒结构在波浪荷载作用下，各方法采用的受力计算模式及其计算结果进行了深入剖析，明确了一些概念性问题，有助于促进本课题的进一步发展。  相似文献   

大直径圆筒振动下沉动力分析方法研究     

李振国  郭海燕 《中国海洋大学学报(自然科学版)》2003,33(4):643-649

本文运用纵向强迫振动多自由度结构和土体等代流变模型 ,对大直径圆筒振动下沉过程进行模拟计算 ,确定在振动锤作用下大直径圆筒的动力响应、筒壁峰值应力和可沉入性 ,并通过工程试验结果验证模拟计算方法的适用性 ,为施工控制提供依据。  相似文献   

Rotating flow past a short,sliced cylinder at finite Rossby number     

K. A. Polzin  M. Angelats I Coll  M. R. Foster 《地球物理与天体物理流体动力学》2013,107(1-2):67-103

Abstract

Flow past a short obstacle in a rotating reference frame generates a wake that is crucial to the overall flow structure if the Rossby number is of the order of the quarter power of the Ekman number. We present here a theory for such flows for the case when the obstacle's top is an oblique, planar surface. The results arise from a combination of asymptotic analysis and numerical computation, and show that even weak asymmetry generates significant global effect on the entire flow-field. Comparisons with the experiments reported by Foster and Davies (1996) are generally good when the high edge is at 90° to the oncoming flow.  相似文献