期刊文献+
共找到6篇文章
< 1 >
每页显示 20 50 100
Application of Three-Dimensional Visual Simulation in Tidal Defense Engineering 被引量:1
1
作者 钟登华 杨斌 +2 位作者 李文倩 刘东海 佟大威 《Transactions of Tianjin University》 EI CAS 2013年第1期1-9,共9页
Any tidal defense engineering involves the collection and analysis of massive information about engineering structures and their surrounding environment. Traditional method, which is carried out mainly by means of two... Any tidal defense engineering involves the collection and analysis of massive information about engineering structures and their surrounding environment. Traditional method, which is carried out mainly by means of twodimensional drawings and textures, is not efficient and intuitive enough to analyze the whole project and reflect its spatial relationship. Three-dimensional visual simulation provides an advanced technical means of solving this problem. In this paper, triangular irregular network (TIN) model simplified by non-uniform rational B-splines (NURBS) technique was used to establish the digital terrain model (DTM) of a super large region. Simulation of dynamic water surface was realized by combining noise function with sine wave superposition method. Models of different objects were established with different modeling techniques according to their characteristics. Application of texture mapping technology remarkably improved the authenticity of the models. Taking the tidal defense engineering in the new coastal region of Tianjin as a case study, three-dimensional visual simulation and dynamic roaming of the study area were realized, providing visual analysis and visible demonstration method for the management and emergency decision-making associated with construction. 展开更多
关键词 tidal defense engineering three-dimensional visual simulation simulation modeling
下载PDF
Numerical simulation of three-dimensional tidal current in the Bobal Sea 被引量:1
2
作者 Den Zhenxing Yang Lianwu and Jose Ozer 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1994年第2期155-172,共18页
The model equations with tbree-dimensional, time-dependent, nonlinear Navier-Stokes equations are transformed by sigma-transformation.On the basis of the process splitting technique, the fluid flow problems are divid... The model equations with tbree-dimensional, time-dependent, nonlinear Navier-Stokes equations are transformed by sigma-transformation.On the basis of the process splitting technique, the fluid flow problems are divided into two parts:the vertically-intopated equations (external mode) and the vertical structure equations(internal mace). The first set of equations being the propagation of the tidal weves and the ADI numerical scheme has ben chosen to solve them. Conerning the vertical structure equations, they are solved by means of leapfrog stepping procedure.The main features of the tide and associated tidal current in the Bohai Sea are examined with this 3-D model.To have a good reproduction of vertical structure, the column is divided into 10 layers and the M2 tidal current is computed in detail. The simulation reveal the spetial structure and some important characteristics of the tidal current of the Bohai Sea. The application of the 3-D madel to forecasting of the tidal current in the Bobal Sea has been Performed as an illustration. 展开更多
关键词 Numerical simulation of three-dimensional tidal current in the Bobal Sea
下载PDF
Application of Line Boundary Technique to 2D Tidal Current Simulation
3
作者 宋志尧 薛鸿超 严以新 《China Ocean Engineering》 SCIE EI 1999年第4期399-410,共12页
To deal with the problems concerning the shore boundary, moving boundary and engineering boundary which are encountered frequently in 2D tidal current simulation by the finite difference method, the concept of line bo... To deal with the problems concerning the shore boundary, moving boundary and engineering boundary which are encountered frequently in 2D tidal current simulation by the finite difference method, the concept of line boundary is introduced and studied here, and then the line boundary technique in common use is proposed in this paper. Analysis of some calculation cases shows that this technique is practical, effective, and simple in 2D tidal current simulation involving different boundaries. 展开更多
关键词 line boundary technique shore boundary and engineering boundary moving boundary tidal current simulation
下载PDF
Numerical Investigation of Flow Motion and Performance of A Horizontal Axis Tidal Turbine Subjected to A Steady Current 被引量:8
4
作者 李林娟 郑金海 +2 位作者 彭于轩 张继生 吴修广 《China Ocean Engineering》 SCIE EI CSCD 2015年第2期209-222,共14页
Horizontal axis tidal turbines have attracted more and more attentions nowadays, because of their convenience and low expense in construction and high efficiency in extracting tidal energy. The present study numerical... Horizontal axis tidal turbines have attracted more and more attentions nowadays, because of their convenience and low expense in construction and high efficiency in extracting tidal energy. The present study numerically investigates the flow motion and performance of a horizontal axis tidal turbine with a supporting vertical cylinder under steady current. In the numerical model, the continuous equation and incompressible Reynolds-averaged Navier-Stokes equations are solved, and the volume of fluid method is employed to track free surface motion. The RNG k-ε model is adopted to calculate turbulence transport while the fractional area/volume obstacle representation method is used to describe turbine characteristics and movement. The effects of installation elevation of tidal turbine and inlet velocity on the water elevation, and current velocity, rotating speed and resultant force on turbine are discussed. Based on the comparison of the numerical results, a better understanding of flow structure around horizontal axis tidal turbine and turbine performance is achieved. 展开更多
关键词 horizontal axis tidal turbine numerical simulation turbine performance flow motion steady current marine renewable energy
下载PDF
Numerical and Experimental Study of the 3D Effect on Connecting Arm of Vertical Axis Tidal Current Turbine 被引量:2
5
作者 郭伟 康海贵 +2 位作者 陈兵 谢宇 王胤 《China Ocean Engineering》 SCIE EI CSCD 2016年第1期83-96,共14页
Vertical axis tidal current turbine is a promising device to extract energy from ocean current. One of the important components of the turbine is the connecting arm, which can bring about a significant effect on the p... Vertical axis tidal current turbine is a promising device to extract energy from ocean current. One of the important components of the turbine is the connecting arm, which can bring about a significant effect on the pressure distribution along the span of the turbine blade, herein we call it 3D effect. However, so far the effect is rarely reported in the research, moreover, in numerical simulation. In the present study, a 3D numerical model of the turbine with the connecting arm was developed by using FLUENT software compiling the UDF(User Defined Function) command. The simulation results show that the pressure distribution along the span of blade with the connecting arm model is significantly different from those without the connecting arm. To facilitate the validation of numerical model, the laboratory experiment has been carried out by using three different types of NACA aerofoil connecting arm and circle section connecting arm. And results show that the turbine with NACA0012 connecting arm has the best start-up performance which is 0.346 m/s and the peak point of power conversion coefficient is around 0.33. A further study has been performed and a conclusion is drawn that the aerofoil and thickness of connecting arm are the most important factors on the power conversion coefficient of the vertical axis tidal current turbine. 展开更多
关键词 connecting arm vertical axis tidal current turbine laboratory experimental study 3D numerical simulation UDF
下载PDF
A Spatially Dependent Nudging Method and Its Application to a Global Tide Assimilation
6
作者 Li LIU Xue'en CHEN 《Advances in Atmospheric Sciences》 SCIE CAS 2024年第12期2464-2477,共14页
Tides represent a crucial dynamic process in the ocean and play a vital role in both marine and atmospheric studies,thus,accurate simulation of tidal processes is of the utmost importance in tidal circulation models.B... Tides represent a crucial dynamic process in the ocean and play a vital role in both marine and atmospheric studies,thus,accurate simulation of tidal processes is of the utmost importance in tidal circulation models.Bazed on the sequential data assimilation method and the concept of the Kalman gain matrix,this paper proposes a new nudging method with spatially dependent coefficients for tidal assimilation.The spatial-dependent nudging method not only retains the advantages of the traditional nudging method but also facilitates the direct determination of a more reasonable spatial distribution of nudging coefficients.Utilizing the M_(2)tidal constituent(the main lunar semidiurnal tide)as an illustration,we conducted assimilation experiments of sea-level data to the barotropic circulation and tide model to assess the global harmonic constants of the M_(2)constituent.The results demonstrate that the spatial-dependent nudging method successfully mitigates deviations of tidal phase lag.Following assimilation using the new method,the deviations of the M_(2)tidal amplitude and phase lag can be reduced by 47%and 18%compared to the traditional nudging method,respectively,while the respective values for the non-assimilated case are as much as 9%and 11%.We also applied the S-nudging method to realistic tidal simulations and noted a significantly enhanced effectiveness relative to traditional methods,making it highly valuable for modeling oceanic tidal circulations. 展开更多
关键词 nudging method assimilation ocean model tidal simulation
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部