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The power coefficient of bidirectional tidal stream turbine obtained by CFD method is 39.36% at the design tip speed ratio.
The comparison between experimental results and numerical prediction results is shown in Fig.1, and the power coefficients obtained by CFD method are almost the same with experiment results.
Fig.1 The comparison between experimental and CFD Blade design and numerical simulation In this paper, the bidirectional airfoil should be fore-aft symmetry to obtain the same power from the both of the tidal current directions.
Computer Simulation, 2010, 27(3):276-280 (in chinese).

Numerical Study of a Flap Rudder Based on Turbulence Model LES Shuguang Wu1, Hean Liu2,a* 1Modern Education Technology Center, Hunan University of Technology, China 2Hunan City University, China a liuheanlaoshi@sina.com * Corresponding author: Hean Liu (liuheanlaoshi@sina.com) Keywords: Flap rudder, CFD, LES, Vorticity Abstract.
The flap rudder flow field at Re 1.4×106 is calculated using computational fluid dynamics (CFD) method.
Large eddy simulation (LES) turbulence model is adopted.
Sunho Park[4] carried out simulations performed for various devices aimed at controlling the gap flow in two-dimensional and three-dimensional domains using the Reynolds-averaged Navier–Stokes equations.
In order to study flow mechanism and boundary layer separation more clearly, the large eddy simulation turbulence model was used.

The hydrofoils were tested through computational fluid dynamic simulation.
The inlet speed is varied accordingly for different simulations.
Through repetitive iterations and rotations of the blades during simulation determined that after 3 revolutions the results become steady shown in Fig 2.
CFD results have slightly under predicted the torque, since the CFD geometry did not have an axial shaft and frame as shown in Fig. 4.
CFD predicted maximum torque of 2.9 Nm at 40 rpm.

Large Eddy Simulation of Unsteady Flow in a Mixed flow Pump Guide Vane Yibin Li1, Rennian Li1,a and Xiuyong Wang1 1School of Energy and Power Engineering, Lanzhou University of Technology No.287 Langongping Road, Lanzhou, 730050, China, alirn@lut.cn Keywords: Mixed-flow pump, guide vane, pressure fluctuation, vortex, LES, CFD Abstract.
Due to the high price, time costing and lag of the experimental method, and with the development of fluid dynamics, CFD (Computational Fluid Dynamics) numerical calculation technology has been widely used in the field of three dimensional turbulence numerical simulation with advantage of short period and leading character.
Miorini, et.al.[3] discover the blade tip leakage vortex structure and unsteady flow mechanism of mixed-flow pump by PIV (Particle Image Velocimetry) and CFD (Computational Fluid Dynamics).
Doing unsteady flow numerical simulation of inner flow field in the mixed flow pump can forecast the characteristics of pressure fluctuation through analyzing the complexity of mixed flow pump inner flow field by using numerical simulation, which has great significance for the project.
Comparing to the prediction of Reynolds-averaged Navier-Stokes (RANS)equations, the CFD unsteady performance prediction cannot forecast the H-Q positive slope precisely basing on the equations.

The first model of CFD in HiTAC effort originated from Japanese industry.
Coelho and Peters carried out numerical simulations of FLOX burner.
Khoshhal et al. performed the numerical study using CFD modeling in an industrial boiler for HiTAC.
Sies, Mohsin, Numerical simulation of confined vortex flow using a modified k- epsilon turbulence model, CFD Letters, vol. 1, pp. 87-94, 2010
Peters, Numerical simulation of a mild combustion burner, Combustion and Flame, vol. 124, pp. 503-518, Feb 2001

Simulation Analysis Model of CFD Analysis.
This paper established two kinds of CFD model: Traditional model and optimization model.
FLUENT simulation and result analysis.
Simulation results of the traditional model Figure 4 is the simulation results of water hydraulic poppet valve of the traditional model.
Simulation results of the optimization model Figure 5 is the simulation results of water hydraulic poppet valve of the optimization model.

To this aim, a design procedure based on seven steps has been defined and reported below. 1) Generation of a parametric CAD model for the swept-mounted airfoil installed in the wind tunnel with flat walls. 2) CFD mesh generation associated to the CAD model. 3) CFD flow simulations for the “infinite span” WT model, replacing solid sidewalls with periodic boundaries. 4) Extraction of typical streamlines shape from the CFD solution back to the CAD environment. 5) CAD design of the contoured sidewalls based on the reference streamline. 6) CFD mesh generation for the contoured WT configuration. 7) Flow simulation for the contoured WT configuration.
CFD Simulations.
CFD evaluations have been performed using CFD++, the commercial CFD code used by Piaggio Aero Industries, which is based on the finite volume method.
Further simulations for slightly modified configuration were performed by FOI using the EDGE code [4].
[3] Metacomp Technologies Inc., CFD++User Manual – Version 8.1, pages 531-533

The Simulation Study of a new-type Frictionless Pneumatic Cylinder Xiao Zhu1,a, Guoliang Tao1,b,Pengfei Qian1, Deyuan Meng1, He Zuo1 1The State Key Lab of Fluid Power Transmission and Control, Zhejiang University, Hangzhou, 310027, China axiaozhu@zju.edu.cn, bgltao@zju.edu.cn Keywords: Frictionless Cylinder, Air Bearing, FEM, Simulation Abstract.
Similar work has been done by Xue-Dong Chen and Xue-Ming He [3] with the help of CFD numerical method.
Renn and Hsiao [4] made an experimental and CFD study on the mass flow rate(MFR) characteristics of orifice-compensated aerostatic bearings.
They found that MFR calculated from the theory, which assumes orifice-type restrictor as a nozzle, might cause large error, and they modified the critical-pressure ratio of the restrictor based on the results of experiments and simulations.
Experimental and CFD study on the mass flow-rate characteristic of gas through orifice-type restrictor in aerostatic bearings.

A three dimensional computational analysis has been done by finite volume discretization method using ANSYS Fluent 14 CFD commercial software.
The simulation boundary conditions are provided to capture the wave properties near to the Shchelkin spiral wall as shown in Fig. 3.
This grid size is maximum smallest grid size for best meshing accuracy and less time consuming simulation.
Further simulations gives constant propagation velocity at δ=0.84m iso-surface distance.
Pandey, Effect of Blockage Ratio on Detonation Flame Acceleration in Pulse Detonation Combustor Using CFD, Applied Mechanics and Materials, Vol. 656, pp 64-71, 2014

Modeling technology and simulation for micro-mechanical gas-flow level-gesture sensor is explained.
Through ANSYS－FLOTRAN CFD program and by means of a series of procedures, such as 3d-modeling, network modifying, loads applying and equation solving, FEM analysis has been obtained.
Choose ANSYS-FLOTRAN CFD analysis function; defining the type of unit.
Meshing is an important step in modelling, which has a great influence on precision and simulation time.
Practical engineering simulation and its application in practice on ANSYS [M].Xi’an：Northwestern Polytechnical University Press，1999.221