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The results of numerical simulations will be presented in the Part 2.
Robustness, economy, and reasonable accuracy for a wide range of turbulent flows explain its popularity in industrial flow and heat transfer simulations.
Jafarizadeh, Numerical Investigation of Heat Transfer and Fluid Flow Structure Simulation in a Divergent/Straight/Convergent Ribbed Duct, M.Sc. thesis, University of Yazd, Iran, (2006) [4] H.
Wilcox, Turbulence Modeling for CFD, DCW, Industries, Inc, (1994) [11]V.
Chen, Evaluation of Various Turbulence Models in Predicting Airflow and Turbulence in Enclosed Environments by CFD: part-1: summary of prevalent turbulence models, HVAC&R Research, 13(6), (2007) [14]B.E.

The numerical simulation and visual analysis of the aboved flow field was carried out.
In the valve port, the mass flow simulation value was compared with the calculated value.
The simulation and analysis of the results When pressure difference is 1MPa and the valve port openings are different, the results of pressure and velocity simulation are shown in Fig. 5, Fig. 6 and Fig. 7.
Fig. 8 Spool valve’s diagram of flow Fig. 9 Mass flow of flow field simulation and theoretical Table 2 The mass flow of simulation and theoretical calculation when pressure difference is 1MPa Valve opening 1(mm) 1.5(mm) 2(mm) Mass flow (kg/s) Simulation value 0.0741 0.1157 0.1568 Cd=0.61 0.0788 0.1192 0.1580 Cd=0.56 0.0723 0.1094 0.1451 Compared with the results of the simulation, it can be seen that the simulation result is identical with theoretical calculation result, which has certain theory significance and practical value to improve the performance of the servo valve.
(In Chinese) [2] Fujun Wang: Analysis of computational fluid dynamics: theory and applications of CFD software.

Florian et al. investigated the effect of resonator curvature on the thermoacoustic effect using CFD simulation in his work [2].
He discussed the influence of a curved resonator on the thermoacoustic engine using CFD analysis.
However, no experimental work was carried out as he only focused on the numerical simulation.
[2] Florian Zink, Jeffrey Vipperman, and Laura Schaefer, CFD simulation of a thermoacoustic engine with coiled resonator, International Communications in Heat and Mass Transfer, (2010)

Simulation of the main ecological parameters Simulation of overshadowing and sunlight hours.
Simulation and prediction of environmental noise.
Simulation of wind environment.
Simulation of weak wind zone.
Wang, in: Computational Fluid Dynamics Analysis—CFD Principles and Applications, edited by Qinghua University Press, Beijing (2007) (in Chinese) [3] Z.F.

Research on Numerical Simulation of Support Interference for Dynamic Derivatives at Hypersonic Flight Speeds Liu Xua, Liu Weib and Zhao Yunfeic College of Areospace Science and Engineering, National University of Defense Technology, Changsha, China anudt@sina.cn, bfishfather6525@sina.com, czhaoyf08@126.com Keywords: CFD; Hypersonic; Support Interference; Dynamic Derivative; Least Squares Abstract.
For the special experiment of dynamic derivatives, no numerical simulation of support interference has yet been systematically studied.
The numerical simulation of support interference for identification of dynamic derivatives with 7º blunted cone under the hypersonic condition was done in this paper.
An unsteady N-S equation is used for numerical simulation of small-amplitude forced simple harmonic vibration with 7º blunted cone in this paper, and a dynamic damping derivative is achieved by numerical identification.
Simulation Example of Hypersonic Missile Module In this paper, HBS (Hyper Ballistic Shape) profile is used as a verification example, and HBS profile is a module of hypersonic missile profile.

Domain Size and Grid Generation The simulation of this paper is 2 dimensions, and the computational fluid dynamics software package used to complete all the simulations discussed in this paper was Fluent6.2.
Previous work has shown that computational fluid dynamics (CFD) can be used to successfully match experimental measurements of both velocity and temperature profiles for slot die[1,2].
All the simulations discussed in this paper were run for the die type shown in Fig. 2.
Fig.1 presents the computational domain used in the simulations for the blunt die.
Numerical Modeling and Simulation Parameters As shown in Fig. 2, the computational domain begins at a position 5 mm above the plane of the die face.

VIV of the cylindrical structure at subcritical Reynolds number (Re) of 3.8 x 104 is studied using a RANSE based CFD transient fluid structure interaction dynamic simulation model employing a user defined function for modeling the response.
The two dimensional (2D) VIV simulations are carried out using RANSE based CFD method.
From the numerical simulations and the subsequent analysis the average flow and motion parameters are as reported in Table 2.
At the investigated mass ratio, a hybrid mode of vortex shedding is observed from the numerical simulations.
Three-dimensional numerical simulation of two-degree-of-freedom VIV of a circular cylinder with varying natural frequency ratios at Re= 500.

Through the simulation, the variations of flow field with different distance between the adjacent cylinder and different Reynolds number are investigated.
For low Reynolds number(Re=200), the flow past three infinite long cylinders with equal column arranged according to the triangle was studied [1];A review of the CFD studies about the vortex shedding flow around cylinder and flow field configuration is found[2];Large eddy simulation is used to simulate the two-dimensional flow field around the single cylinder with the change of Reynolds number[3];For multiple columns, the number of columns, column arrangement, the distance between cylinder and Reynolds number have a great influence on flow field [4-5].
Numerical Simulation of Three Equispaced Circular Cylinders [J].
Large eddy simulation of flow around two circular cylinders [J].
[6] M.Zhao, C.Liang,B.Teng.Numerical simulation of viscous flow past two circular cylinders of different diameters[J].Applied Ocean Research,2005,27(1):39-55.

The air/oil two-phase flow in a simplified bearing chamber model in an aero-engine is simulated by means of discrete phase model (DPM) and wall-film model with CFD approach.
The simulation results coincide with the existing experimental data.
Therefore, numerical simulation is an efficient method.
Therefore, it is indicated that numerical simulation model is right.
Results of numerical simulation coincide well with experiments data which verify the calculation model.

Yuh Ming Ferng [8] developed a 3D full cell CFD model and investigated the effect the parallel and serpentine flow with different depth of flow channels.
The simulation has been solved by simultaneous equations like conservation of mass, momentum, energy, species, Butler–volmer equation, Joule heating reaction and Nernst equation to obtain reaction kinetics of PEM fuel cell namely mass fraction of O2, and H2O, pressure and current flux density distribution on flow channel.
Results and Discussions From the analysis of the models using CFD software package, the current values corresponding to the cell voltages were obtained.
[8] Yuh Ming Ferng, Ay Su, A three-dimensional full-cell CFD model used to investigate the effects of different flow channel designs on PEMFC performance, International Journal of Hydrogen Energy, Vol.32 (2007), p.4466 – 4476