期刊文献+
共找到7篇文章
< 1 >
每页显示 20 50 100
高土石坝宏细观坝水动力流固耦合理论研究进展 被引量:2
1
作者 岑威钧 孙辉 陈亚南 《水利水电科技进展》 CSCD 北大核心 2013年第6期10-16,共7页
高土石坝遭遇强烈地震时会与坝面库水及坝内孔隙水发生动力流固耦合相互作用,分别从宏观坝水耦合系统和细观水土耦合系统两个角度对高土石坝坝水动力流固耦合理论的研究历史、主要研究成果和研究趋势进行了阐述评价。对宏观尺度的大坝... 高土石坝遭遇强烈地震时会与坝面库水及坝内孔隙水发生动力流固耦合相互作用,分别从宏观坝水耦合系统和细观水土耦合系统两个角度对高土石坝坝水动力流固耦合理论的研究历史、主要研究成果和研究趋势进行了阐述评价。对宏观尺度的大坝与坝面库水流固耦合作用,主要从早期坝水相互作用模型、库水运动精细分析方法以及流固耦合系统坐标描述等方面做出评述;对细观尺度的坝内水土耦合作用,主要从早期解耦或拟耦合的水土动力分析方法、基于Boit动力固结理论的细观水土动力流固耦合,以及基于混合物理论的细观水土动力流固耦合等方面做出评述。综合两个尺度的流固耦合作用研究现状,建议对高土石坝建立水库-土石坝-孔隙水的宏细观整体动力流固耦合系统进行综合研究,并指出了当前高土石坝宏细观坝水动力流固耦合理论尚待继续深入研究的若干相关问题。 展开更多
关键词 高土石坝 孔隙 宏观坝水动力流固耦合 细观动力固耦合 动力分析
在线阅读 下载PDF
应用于海洋物性监测仪的小型浮标水动力分析 被引量:2
2
作者 梁冠辉 孙宝楠 +3 位作者 薛宇欢 陶常飞 官晟 周兴华 《海洋科学进展》 CAS CSCD 北大核心 2021年第1期136-145,共10页
为验证研制的国产气象水文传感器的性能,设计了直径3 m的圆盘式小型浮标,拟搭载所有传感器在2000 m以深海域开展应用试验。统计了试验海域的有义波高、波浪周期、最大风速和表层流速等环境参数,计算了浮标的质量、重心、吃水、受力投影... 为验证研制的国产气象水文传感器的性能,设计了直径3 m的圆盘式小型浮标,拟搭载所有传感器在2000 m以深海域开展应用试验。统计了试验海域的有义波高、波浪周期、最大风速和表层流速等环境参数,计算了浮标的质量、重心、吃水、受力投影面积和惯性矩等设计参数。以三维势流理论和波浪辐射-绕射理论为基础,使用AQWA软件在频域内对浮标进行水动力计算,仿真了浮标工作时所受的一阶波浪力、附加质量、附加阻尼和运动幅值响应因子,通过仿真结果对浮标设计方案进行优化,优化后的浮标计算结果随波浪频率变化平缓,幅值合理且无激增点,表明该浮标与工作海域内的波浪没有发生明显谐振,对环境载荷有足够的承受能力,方案可用于浮标研制。 展开更多
关键词 浮标 :动力:频域分析 耐波
在线阅读 下载PDF
Turbulent boundary layers and hydrodynamic flow analysis of nanofluids over a plate 被引量:4
3
作者 AOUINET Hana DHAHRI Maher +2 位作者 SAFAEI Mohammad Reza SAMMOUDA Habib ANQI Ali E. 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第11期3340-3353,共14页
A numerical analysis of the log-law behavior for the turbulent boundary layer of a wall-bounded flow is performed over a flat plate immersed in three nanofluids(Zn O-water,SiO_(2)-water,TiO_(2)-water).Numerical simula... A numerical analysis of the log-law behavior for the turbulent boundary layer of a wall-bounded flow is performed over a flat plate immersed in three nanofluids(Zn O-water,SiO_(2)-water,TiO_(2)-water).Numerical simulations using CFD code are employed to investigate the boundary layer and the hydrodynamic flow.To validate the current numerical model,measurement points from published works were used,and the compared results were in good compliance.Simulations were carried out for the velocity series of 0.04,0.4 and 4 m/s and nanoparticle concentrations0.1% and 5%.The influence of nanoparticles’ concentration on velocity,temperature profiles,wall shear stress,and turbulent intensity was investigated.The obtained results showed that the viscous sub-layer,the buffer layer,and the loglaw layer along the potential-flow layer could be analyzed based on their curving quality in the regions which have just a single wall distance.It was seen that the viscous sub-layer is the biggest area in comparison with other areas.Alternatively,the section where the temperature changes considerably correspond to the thermal boundary layer’s thickness goes a downward trend when the velocity decreases.The thermal boundary layer gets deep away from the leading edge.However,a rise in the volume fraction of nanoparticles indicated a minor impact on the shear stress developed in the wall.In all cases,the thickness of the boundary layer undergoes a downward trend as the velocity increases,whereas increasing the nanoparticle concentrations would enhance the thickness.More precisely,the log layer is closed with log law,and it is minimal between Y^(+)=50 and Y^(+)=95.The temperature for nanoparticle concentration φ=5%is higher than that for φ=0.1%,in boundary layers,for all studied nanofluids.However,it is established that the behavior is inverted from the value of Y^(+)=1 and the temperature for φ =0.1% is more important than the case of φ =5%.For turbulence intensity peak,this peak exists at Y^(+)=100 for v=4 m/s,Y^(+)=10 for v=0.4 m/s and Y^(+)=8 for v=0.04 m/s. 展开更多
关键词 turbulent boundary layers nanofluids hydrodynamic flow wall shear stress turbulent intensity
在线阅读 下载PDF
CFD prediction of local scour hole around bridge piers 被引量:5
4
作者 ZHU Zhi-wen LIU Zhen-qing 《Journal of Central South University》 SCIE EI CAS 2012年第1期273-281,共9页
In order to predict the local scour hole and its evaluation around a cylindrical bridge pier, the computational fluid dynamics (CFD) and theories of sediment movement and transport were employed to carry out numeric... In order to predict the local scour hole and its evaluation around a cylindrical bridge pier, the computational fluid dynamics (CFD) and theories of sediment movement and transport were employed to carry out numerical simulations. In the numerical method, the time-averaged Reynolds Navier-Stokes equations and the standard k-e model were first used to simulate the three-dimensional flow field around a bridge pier fixed on river bed. The transient shear stress on river bed was treated as a crucial hydrodynamic mechanism when handling sediment incipience and transport. Then, river-bed volumetric sediment transport was calculated, followed by the modification of the river bed altitude and configuration. Boundary adaptive mesh technique was employed to modify the grid system with changed river-bed boundary. The evolution of local scour around a cylindrical bridge pier was presented. The numerical results represent the flow pattern and mechanism during the pier scouring, with a good prediction of the maximum scour hole depth compared with test results. 展开更多
关键词 local scour bridge pier computational fluid dynamics sediment transport
在线阅读 下载PDF
Numerical computation and analysis of unsteady viscous flow around autonomous underwater vehicle with propellers based on sliding mesh 被引量:4
5
作者 高富东 潘存云 韩艳艳 《Journal of Central South University》 SCIE EI CAS 2012年第4期944-952,共9页
The flexible transmission shaft and wheel propeller are combined as the kinetic source equipment, which realizes the nmlti-motion modes of the autonomous underwater vehicle (AUV) such as vectored thruster and wheele... The flexible transmission shaft and wheel propeller are combined as the kinetic source equipment, which realizes the nmlti-motion modes of the autonomous underwater vehicle (AUV) such as vectored thruster and wheeled movement. In order to study the interactional principle between the hull and the wheel propellers while the AUV navigating in water, the computational fluid dynamics (CFD) method is used to simulate numerically the unsteady viscous flow around AUV with propellers by using the Reynolds-averaged Navier-Stokes (RANS) equations, shear-stress transport (SST) k-w model and pressure with splitting of operators (PISO) algorithm based on sliding mesh. The hydrodynamic parameters of AUV with propellers such as resistance, pressure and velocity are got, which reflect well the real ambient flow field of AUV with propellers. Then, the semi-implicit method for pressure-linked equations (SIMPLE) algorithm is used to compute the steady viscous flow field of AUV hull and propellers, respectively. The computational results agree well with the experimental data, which shows that the numerical method has good accuracy in the prediction of hydrodynamic performance. The interaction between AUV hull and wheel propellers is predicted qualitatively and quantitatively by comparing the hydrodynamic parameters such as resistance, pressure and velocity with those from integral computation and partial computation of the viscous flow around AUV with propellers, which provides an effective reference to the shady on noise and vibration of AUV hull and propellers in real environment. It also provides technical support for the design of new AUVs. 展开更多
关键词 computational fluid dynamics sliding mesh wheel propeller autonomous underwater vehicle viscous flow field
在线阅读 下载PDF
Numerical computation and analysis of high-speed autonomous underwater vehicle (AUV) moving in head sea based on dynamic mesh 被引量:2
6
作者 高富东 潘存云 +1 位作者 徐小军 韩艳艳 《Journal of Central South University》 SCIE EI CAS 2012年第11期3084-3093,共10页
Autonomous underwater vehicles (AUVs) navigating on the sea surface are usually required to complete the communication tasks in complex sea conditions. The movement forms and flow field characteristics of a multi-mo... Autonomous underwater vehicles (AUVs) navigating on the sea surface are usually required to complete the communication tasks in complex sea conditions. The movement forms and flow field characteristics of a multi-moving state AUV navigating in head sea at high speed were studied. The mathematical model on longitudinal motion of the high-speed AUV in head sea was established with considering the hydrodynamic lift based on strip theory, which was solved to get the heave and pitch of the AUV by Gaussian elimination method. Based on this, computational fluid dynamics (CFD) method was used to establish the mathematical model of the unsteady viscous flow around the AUV with considering free surface effort by using the Reynolds-averaged Navier-Stokes (RANS) equations, shear-stress transport (SST) k-w model and volume of fluid (VOF) model. The three-dimensional numerical wave in the computational field was realized through defining the unsteady inlet boundary condition. The motion forms of the AUV navigating in head sea at high speed were carried out by the program source code of user-defined function (UDF) based on dynamic mesh. The hydrodynamic parameters of the AUV such as drag, lift, pitch torque, velocity, pressure and wave profile were got, which reflect well the real ambient flow field of the AUV navigating in head sea at high speed. The computational wave profile agrees well with the experimental phenomenon of a wave-piercing surface vehicle. The force law of the AUV under the impacts of waves was analyzed qualitatively and quantitatively, which provides an effective theoretical guidance and technical support for the dynamics research and shape design of the AUV in real complex environnaent. 展开更多
关键词 computational fluid dynamics dynamic mesh autonomous underwater vehicle (AUV) MOTION head sea viscous flowfield
在线阅读 下载PDF
Numerical investigation of optimal geometry parameters for ejectors of premixed burner
7
作者 刘凤国 张蕊 +2 位作者 刘文博 翟军 郑斌 《Journal of Central South University》 SCIE EI CAS 2014年第3期1011-1016,共6页
An ejector of low NO~ burner was designed for a gas instantaneous water heater in this work. The flowing and mixing process of the ejector was investigated by computational fluid dynamics (CFD) approach. A comprehen... An ejector of low NO~ burner was designed for a gas instantaneous water heater in this work. The flowing and mixing process of the ejector was investigated by computational fluid dynamics (CFD) approach. A comprehensive study was conducted to understand the effects of the geometrical parameters on the static pressure of air and methane, and mole fraction uniformity of methane at the outlet of ejector. The distribution chamber was applied to balance the pressure and improve the mixing process of methane and air in front of the fire hole. A distribution orifice plate with seven distribution orifices was introduced at the outlet of the ejector to improve the flow organization. It is found that the nozzle exit position of 5 mm and nozzle diameter d 〉1.3 mm should be used to improve the flow organization and realize the well premixed combustion for this designed ejector. 展开更多
关键词 EJECTOR computational fluid dynamics (CFD) bumer distribution orifice premixed combustion
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部