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A numerical model for laser cutting process is developed based on the Computational fluid code Fluent-cfd.
In the case of circularly or un-polarized laser radiation , The averaged absorptivity A can be estimated as the average value of the reflectivities of parallel and perpendicularly polarized radiation RP and RS. [6]: (7) Parameters used in the simulation The commercial code Fluent 6.3 CFD, to which several modules were appended (User Defined Functions UDF) was used to accomplish the simulation [7].The calculation domain is illustrated in figure 1.b, including the substrate and part of the gas region (gas phase).
In order to make the calculation tractable, small physical size of the specimens, 4mm × 5mm × 1.5mm is employed in the simulation and a uniform cell grid mesh was used.
The physical properties used in the simulation corresponding to that for mild steel [8] are shown in table 1.The optical properties n and m (refractive and extinctive indexes) are function of wavelength and different temperature-dependent material properties.
The parameters adopted in the simulation are: laser power: 2 KW, cutting velocity: 50 mm/s, gas velocity: 100-200 mm/s, laser beam radius: 0.5 mm.

Afterwards, import the data to CFD processor Gambit software, using spline curve to fit values at each section point so as to establish a smooth three-dimensional propeller surface.
Figure 3 Calculated value and test value Curve fitting comparison From figure 3 we can conclude: The calculation results and experimental results are basically identical, and the average error is about 3%.on the whole, the simulation result is good, Analyze the error causes, there is a deviation between the physical model and digital model, experimental and simulation conditions cannot be exactly same (for example, the Reynolds number and hydraulic wake).
Therefore, using CFD simulate propeller under open water can satisfy the demand of practical engineering application.
Based on the CFD duct propeller hydrodynamic performance research .
Application and research of propeller hydrodynamic performance calculation by means of CFD.

CFD Simulation for Displacement Deep-vee Vessels on Resistance Influence Factor XIE Yi1, a, XIA Xiang-dong2 1,2College of Naval Architecture and Power, Naval University of Engineering, Wuhan 430033, China a datou-1977@163.com Keywords: Deep-Vee vessels, resistance, RANS equations, CFD.
According to the methods of geometric model generation, grid of meshing, computational domain and boundary conditions setting, numerical simulation of the 3D viscosity flow over eight deep-vee vessels are calculated in this paper.
As can be seen from two figures, the numerical results of total resistance shows a fair agreement with experimental data at numerical simulation velocity range.
SUN, et al: Numerical simulation of free ship model towed in still water.

Numerical Investigation on Transmission Line Conductor Icing Xian Yi1,2, a, Hanjie Huang2 and Zhihong Zhou1,2 1State Key Laboratory of Aerodynamics, Mianyang, 621000 China 2China Aerodynamics Research and Development Center, Mianyang, 621000 China ayixian_2000@163.com Keywords: transmission line conductor, ice accretion, numerical simulation, icing wind tunnel, supercooled droplets Abstract.
A numerical method based on CFD technology for predicting ice accretion on transmission line conductor was presented in the present paper.
In this paper, a numerical method based on CFD technology for predicting conductor icing was presented.
In this paper we adopted the CFD method to carry it.
Fig. 7 Ice shape for different MVD Fig. 8 Ice shape for different LWC Fig. 9 Ice shape for different air speed Fig. 10 Ice shape for different icing time Conclusions A numerical method based on CFD technology for predicting ice accretion on transmission line conductor was presented in the paper.

Numerical Simulation for Part Effect of Ventilation of Extra-long Road Tunnel Sheng Liu1a, Guanglong Zhang2b, Xiaowei Liu2b 1School of Science, Chang’an University, Xi’an, Shaanxi Province, 710064, China 2School of Highway, Chang’an University, Xi’an, Shaanxi Province, 710064, China a86128875@163.com, b87596240@163.com Key words: highway tunnel; semi-transverse ventilation system; part effect; numerical simulation Abstract.
Part resistance coefficients that numerical simulation of the semi-transverse Ventilation under various work condition needs are obtained.
CFD Part Numerical Simulation Distributary resistance coefficient.
The pressures provided by the simulation for jet fan in states of tailwind and windward are both less than standard value showing the failure of expected surge effect.
CFD simulation of fire smoke behavior with transverse ventilation comparison with model test[A]. 10th I SAVVT[C].

Numerical Simulation of Vortex-induced Vibration for Two Circular Cylinder in Tandem Arrangement Jing Zhao 1,a , Haiyan Guo1,b and Xiaomin Li1,c 1 College of Engineering, Ocean University of China, Qingdao, Shandong, 266100, China amirror830@163.com, bhyguo@ouc.edu.cn, clixiaomin0318@163.com, Keywords: CFD; two cylinders; tandem arrangement; vortex-induced vibration; a single and two degrees of freedom.
The results of numerical simulation for a single cylinder by the present method are observed close to the data of experiment.
Besides, other researchers using computational method, and some of these people are trying to solve the FSI problems by coupling computational fluid dynamics (CFD) and computational structural dynamics (CSD).
Murakami[4] extended large eddy simulation to conduct the cases of the flow past out an oscillating 2D square cylinder at cross-flow.
Conclusions In this paper, the vortex-induced vibration of a single and two cylinders separated by 5.5D in tandem arrangement is studied numerically by using CFD and CSD together.

In this study, computational fluid dynamic(CFD) simulation is performed to study the aerodynamic characteristics of the trajectory correction fuze.
In this study, the radial dimension of simulation region is 15 times the radius of the projectile,and the length is 10 times the length of the projectile.[7] b) Mesh Generation The mesh is the carrier of the numerical simulation.
In this study, the simulation model used unstructed grid method.
Selection of turbulence in a aerodynamical simulation of a missile [J].
[10]ANSYS ICEM CFD 14.0 User’s Guide, ANSYS Inc. .

In2009, both 2D and 3D simulations (Figure.2) were carried out using the volume of fluid method (VOF) and compared with experimental data and empirical correlations.
Free Surface Flow of Liquid Slag Simulation.
In2009, both 2D and 3D simulations[7] (Figure.3) were carried out using the volume of fluid method (VOF) and compared with experimental data and empirical correlations published in literature.
Dongsheng, CFD simulation of free surface flow and heat transfer of liquid slag on a spinning disc for a novel dry slag granulation process, Progress in Computational Fluid Dynamics, 10 (2010) 292-299
Tade, Characterizing liquid film thickness in spinning disc reactors, 7th International Conference on CFD in the Minerals and Process Industries.

With the large eddy simulation method, unsteady flow of a single six-blade ruston turbine in stirred tank is numerically simulated and analyzed using CFD software FLUENT.
Large eddy simulation uses the unsteady solution method.
Large eddy simulation is the method between direct numerical simulation (DNS) and Reynolds Averaged Navier-Stokes (RANS).
CFD study of homogenization with dual Rushton turbines: Comparison with experimental results, J.
Large eddy simulations on the flow driven by a Rushton turbine, J.

Therefore, based on the Computational Fluid Dynamics (CFD) and the related theory of safety system science, leak and diffusion processes of high pressure liquid oxygen in spherical tank area, and the subsequent potential oxygen poisoning was analyzed by accident consequence assessment method.
Conclusions Combining CFD with Safety System Engineering, leak and diffusion processes of high pressure liquid oxygen in spherical tank area were numerically predicted.
References [1] State Administration of Production Safety Supervision, in: Safety Assessment, edited by Coal Industry Publisher, Beijing (2005) [2] Jianhua Li, Zhenghua Huang, Xiong Deng, Chlorine Gas Leaking Behavior and Diffusion Model, Proceedings of 2006(Shenyang) International Colloquium on Safety Science and Technology, Shenyang (2006) [3] Yuanhui Wang, Safety System Engineering, Tianjin University Press, Tianjin (1999) [4] Lixing Zhou, in: Turbulence Two Phase Flow and Numerical Simulation of Combustion, edited by Tsinghua University Press (1991) [5] Zong-xiang Li, CFD simulation of spontaneous coal combustion in irregular patterns of goaf with multiple points of leaking air, Jounal of China University of Mining & Technology.2008, 18(4):504-515