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Fire prevention and safety evaluation under the course of construction In this paper, in view of shield machine of the 15.43 meter diameter large section of highway tunnel, the application of Computational Fluid Dynamics (CFD) simulation and the building EXODUS evacuation model analysis.
General model of the shield tunnel The computational fluid dynamics (CFD) model, which is being used to conduct the simulation of the motion of smoke and fume inside shield machine of the tunnel, is calculated out from Fire Dynamic software (FDS4.0) of National Institute of Standards and Technology (NIST) (see fig.2).
CFD simulation analysis model Level3 Level2 Level1 Figure 3.
Three-dimensional version of tunnel CFD model Basic CFD assumptions in the shield tunnel The assumption of The CFD model is that the main temperature both inside and outside is the same, no-ventilation, airflow speed kept as close as possible to zero.
So, the CFD simulation considers all exits as emergency exits, that is, each level is connected by staircases an escape strategy may lead workers to exit via their nearest serviceable exits.

ICEM CFD is used to model a rotor domain, blade domain and stationary fluid domain.
Modeling and simulation is performed in ANSYS-ICEM and CFX.
First a single or stand alone turbine is simulated and analyzed CFD analysis and efficiency.
Difference between fixed and variable pitch vertical axis tidal turbine-using CFD analysis in CFX.
CFD simulation of twin vertical axis tidal turbines system.

The CFD (Computational Fluid Dynamics) method is used to research the turbulent planar impinging jet of gas knives.
In view of the situation, numerical simulation is now presented in this paper.
In numerical simulation of impinging jet, the standard k-ε model and RNG k-ε model have been mostly applied [2-5].
FLUENT 5.4, one kind of CFD software, is implemented in numerical simulation.
It demonstrates that the CFD method can be practically applied in jet field, and that the realizable k-ε turbulence model can successfully predict the impinging jet

The essay designs four layout schemes, using the CFD to simulate them, respectively.
Simulation results 4.1 Temperature Analysis The temperature distribution in the vertical view of four layout schemes is shown in Fig. 2.
References [1] ZHANG Jian, WANG Shugang and ZHANG Tengfei: Numerical simulation of heat transfer between outdoor units of multi-connected split air conditioning systems and ambience [J].
HV&AC, 2010, 40(11):104-107 [2] Multi-splits air-conditioning system. http://baike.so.com/doc/4460188.html [3] WANG Fei, XIAO Yongquan: Simulation and evaluation of building cluster’s wind environment with PHOENICS soft ware [J].
HV&AC, 2008, 38(1): 7-10 [5] LI Meixia, WANG Qiwen: The applications of numerical simulation in natural ventilation design [C].

Commerical CFD codes ANSYS Fluent is used in the present study.
The 3D model, computation domain and mesh for this type of vertical axis wind turbine for CFD simulation is shown in Fig.1(b) and 1(c).
The unstructured tetra mesh are generated using ANSYS ICEM CFD as seen in Fig. 1(c).
This knowledge of simulation is extended to this work.
Numerical simulations are also carried out to study the flow and performance characteristics of this type of wind turbine.

It combines the weakly compressible water source CFD code and FEM shell element code.
Programming code and numerical algorithm We developed a "weakly compressible" CFD code under OpenFoam c++ class libraries according to formula (1), (2) and a pipe analysis finite element code in the FEAP according to formula (3).
In the CFD code, the spatial discretization was performed using a cell centered co-located finite volume method for unstructured meshes with arbitrary cell-shapes.
For the simulations presented in this paper, a second order implicit time scheme is used combined with second order linear interpolation in space, except for the convective terms.
B, 10(4): 71-89 [13]Hongming Zhang.Stuties on numerical simulation of weakly compressible coupling water hammer and cavitation in hydroturbine.

We developed a CFD code applies the omni-tree Cartesian grid to simulate the flow fields around one civil-plane high-lift model using the multi-zone technique.
The capability and performance of the code are assessed by the numerical simulations of the civil-plane high-lift configurations.
Conclusions This paper describes the work of the CFD improvement in the numerical simulation of high-lift model with respect to the Cartesian grid method.
Peter, CFD improvement for high lift flows in the European project eurolift, AIAA Paper 2003-3795
Li, Numerical simulations for transport aircraft high-lift configurations using Cartesian grid methods, Journal of Aircraft, 43(4) 2006 1103-1111.

However, some of the simulation results lack accuracy.
Wang and Yan [4] summarized the CFD applications in biomass thermochemical conversion and system design.
McGrattan et al. [6,7] developed a three-dimensional CFD tool of Fire Dynamics Simulator (FDS) in the fire protection field.
N: CFD Analysis of spatial distribution of various parameters in downdraft gasifier, Procedia Engineering Vol. 51 (2013),.p.764-769 [4] Wang, Y., and Yan, L.: CFD studies on biomass thermochemical conversion-review.
R., Brink, A., and Hupa, M.: CFD modeling to study fluidized bed combustion and gasification, Appl.

To study the flow and swirl characteristics in the variable swirl intake system of a four-valve diesel engine, a numerical simulation with using the three dimensional CFD software AVL-FIRE, was calculated on the intake flow in three types of inlet of the engine.
So the engine can operate in broader range of the swirl intensity in various conditions, so that it can achieve the intake swirl with the best match of the diesel engine conditions [8].In this paper, a CFD numerical simulation was used to research into the intake flow of a diesel engine.
The intake flow characteristics of the two plans are numerical simulated and compared by using the 3-dimension CFD software.
The interaction between the two effects can be analyzed through the results of the numerical simulation.
[7] Ren Lihong, Shu Gequn and Song Rugang, in: The Research and Simulation on Flow Characteristic of Variable Intake System of Motorcycle Engine .

In this study, a lead-acid battery has been simulated numerically using the CFD commercial software package FLUENT.
Recently, Esfahanian et al. [7] introduced an improved and efficient mathematical model for simulation of flooded lead-acid batteries based on Computational Fluid Dynamics (CFD) and Equivalent Circuit Model (ECM).
This model inherited the accuracy of CFD model and the physical understanding of ECM.
Torabi, Numerical simulation of lead-acid batteries using Keller–Box method, J.
Mosahebi, An innovative computational algorithm for simulation of lead-acid batteries, J. power Sources, 176 (2008) 373–380