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The main objective of the present CFD study is to find a new way to reduce the high drag of grid fins and make it easier to fold against the missile body which is usually ogive cylinder.
The CFD study starts with the same numerical method and mesh quality thus the difference of CFD results between the baseline and circular-arc models mainly comes from the difference of their different configurations. 2 Numerical Approach 2.1 Grid fin configuration The model investigated in a recent wind tunnel test is selected as the baseline.
Spalart-Allmaras one-equation turbulent model was used for simulations. 3 Results and discussions 3.1 Validation for baseline model In order to validate the present numerical approach, the computed lift and drag coefficients of the present CFD study at M=1.5 are compared with experimental data as shown in Fig. 3.
Viscous computational fluid dynamic (CFD) simulations were performed to investigate flows over single grid fins and an body-fin configurations in transonic and supersonic flow regions in the range of 0.6-4.0, at 6° angle of attack.
The present simulations show that drag force coefficient can be reduced by using the circular-arc grid fin.

Numerical Simulation of Flow Process of Ammonium Persulfate Crystallizer Yuguang Fan1,a, Ting Wei1,b 1School of Mechanical Engineering, Xi'an Shiyou University, Xi'an, Shaanxi, China, 710065 aygfan@xsyu.edu.cn, btingwei8906@163.com Key words: crystallizer; impeller; draft tube; numerical simulation Abstract.
The method of computational fluid dynamics (CFD) is used to three-dimensional numerical simulation for the fluid flow process of ammonium persulfate crystallizer.
Paddle acting on the fluid produced a complex turbulent flow, so the key to simulation is to choose an appropriate turbulence model.
Figure.1 Ammonium persulfate crystallizer structure diagram Figure.2 Model grid diagram All CFD problems need have boundary conditions to be solved.
Zhu: Study and multi-phase CFD modeling of ammojum sulphate crystallization (Ph.D., Tianjin University, China 2008).

Optimizing Research on the Clad Façade of a High-rise Building using CFD Method Yuan Lei 1, a, Shao Lili 1,b and Xu Xuesong2,c 1 Department of Architecture, Shenzhen University, Guangdong,China 3The Institute of Architecural Design & Research, Shenzhen University, Guangdong,China ayuanlei@szu.edu.cn, bshaolili0420@163.com, cxx_song@126.com Keywords: CFD, natural ventilation, temperature distribution, U-value, SHGC Abstract.
Using Airpak as CFD tool, the study simulates and analyses how the openings and thermal characteristics of the clad façade work on the distribution of temperature and ventilation in the atrium of a high-rise building in Shenzhen.
(See Fig. 1) Fig. 1 Model of the building used in simulation Although there is no roof on the top of the atrium, most part of the atrium are enveloped by the clad facades, which results in climatic buffer spaces for the inner rooms.
Study scheme In the study, CFD (Computational Fluid Dynamics) simulation is used as the tool of analyzing and comparing thermal environment of the atrium with different openings and glass types.
The time is set to 15:00 on July 10th in the simulation, since it represents almost the hottest time of the year in Shenzhen; then, solar radiation intensity is calculated automatically.

With the sustainable development of computer and CFD, numerical methods have become an important means for product design.
Fig.1 Geometric model Numerical simulation methods Turbulence models.
Numerical simulation of effect of inlet configuration on square cyclone separator performance[J].
CFD–DEM simulation of the gas–solid flow in a cyclone separator[J].
CFD parallel computing and load balancing research using multi-block structured grids[J].

*Email: yc9316@163.com Keywords: CFD analysis, parameter study, SOFC model, elementary surface reactions, transport process.
The CFD model simulation has been proved an effective method for SOFC research.
In this work, a 3D CFD model is developed to simulate the working processes in SOFC’s anode.
In this work, a fully 3D CFD approach is developed to model a SOFC anode including fuel channel, porous anode and interconnect structure.
CFD Solution Methods An 3D CFD code in Fortran language is developed to solve the governing equations.

CFD simulations solve the Navier-Stokes equations, which account for all fluid mechanical effects.
By using the CFD method, a lot of intricate questions could be well answered.
In Section III, we present materials and methods for CFD research.
Simulations were carried out for 6000 time steps to simulate swimming for twenty tailbeat periods.
Adding turbulence to the three-dimensional simulation would provide the most accurate and realistic numerical simulation of mechanical fin motion.

Simulation of Liquid Flowing over Surfaces with Micro- structure Zhijun Xi1, a, Gang Li1, b,* 1School of Mechanical and Electrical Engineering, Xinyu University, Xinyu 338004, China 2School of Mechanical and Electrical Engineering, East China Jiaotong University, Nanchang 330013, China axyxzj2000@163.com, bligang0794@163.com * Author to whom correspondence should be addressed Key words: Simulations, Slip velocity, Drag reduction, Pressure drop Abstract: The exist shear-free air-water interface at the fluid-solid houndary is one important reason for drag reduction of ultrahydrophobic surface.
Rectangular microchannel flows with various periodic micro-structured wall by introducing velocity slip boundary condition at low Reynolds number is investigated through computational fluid dynamics simulations(CFD).
This paper will simulate numerically the shear-free slip mechanism of periodic micro-structured wall through Computational Fluid Dynamics (CFD) in the slip boundary condition.
Grid is of geometrical expressed form of CFD model, and also media of simulation and analysis.
Fig.4 Pressure drop vs. slip velocity Fig.5 Pressure drop vs. flow velocity Conclusion A carefully designed set of numerical models with CFD method have been shown that drag reduction in microchannels is possible when the walls of the microchannel are designed with well-defined periodic microstructure.

ASME nozzle CFD model is defined with triangular mesh.
Fig. 3 gives the comparison about contours of Mach number between full CFD model and internal only CFD model.
Fig. 5 Comparison between CFD results and ASME nozzle test data 4.
Internal only CFD model and supersonic outflow boundary can reduce CFD model while providing accurate choked flow solution.
Numerical simulation of dynamic stall using upwind methods and RNG turbulence models．AIAA98-0419 (1998)

In this paper, based on Navier-Stokes equations numerical simulation and two dimensional wind tunnel testing, the drag measuring technique for high lift configuration in low speed wind tunnel is researched.
In this paper, detailed measuring and numerical simulation for the flow field in 2-D drag test are carried out to improve the method of measuring and data processing in hope to overcome the difficulty that now exist in multi-airfoil drag testing.
Numerical Simulation.
The Navier-Stokes equations for 2-D compressible viscous flow is solved by the finite volume method that proposed by Jameson, and local time step, implicit residual smooth and some other accelerating convergence methods are applied in numerical simulation.
And this accord with the CFD results of wake flow field in last section.

Delayed Detached Eddy Simulation.
In the present study CFD simulation with delayed detached eddy simulation (DDES) are performed to investigate an open cavity at Mach 0.85.
The cavity flow field and acoustic sources are simulated using CFD method based on DDES with results compared with experimental data.
When we turn this standard S-A model to a hybrid RANS/LES form which is called Detached Eddy Simulation (DES), in Eq. (2) will be replaced by
Ashworth: Weapon Bay Aerodynamics-Wind-Tunnel Trials and CFD Modelling by QinetiQ UK.