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A simulation study for high temperature chemical vapor deposition (HTCVD) of silicon carbide (SiC) is presented.
Numerical simulation [3-6] could be a powerful tool to design a reactor and to determine growth conditions.
Simulation Method Gas Phase Reaction Rate.
Commercially available software CFD-ACE+ was used under a two dimensional model.
Main part of the simulation was the same of the Ref

China liuzheyoungman@163.com Keywords: Centrifugal fan, Numerical simulation, Flow separation, Stall characteristics; Abstract.
With the development of CFD, using numerical software to simulate the complex flow field has become an important method.
In this paper a detailed numerical simulation under different angle has been carried out based on the Realizable turbulence model with Fluent.
“Numerical Simulation on the Dynamic Stall Process of Airfoils in Transonic Flow”.ACTA AERODYNAMICA SINICA, vol.16,1998,pp.205-209
“Simulations of viscous transonic flows over lifting airfoils and wings”.Computers & Fluids,vol.36,2007,pp.39-52

Fire simulation programs are classified into zone models and field models.
The FDS was developed by the National Institute of Standards and Technology (NIST), based on Computational Fluid Dynamics (CFD), and uses large eddy simulation (LES) for computing flow patterns.
The essential fire simulation positions are shown in Figs. 1-4.
Guo, Numerical simulation of fire-induced flow a stairwell, Build.
Huang, Using fire dynamic simulation (FDS) to reconstruct an arson fire scene, Build.

By combining CFD numerical simulation [2] technology and system identification principle, the method of least squares embed into Fluent [3] which get transfer function of wood drying kiln control system.
The input of the fuzzy controller are and , output are, , ： ,, (3) (4) Self-tuning process of the controller is shown in Fig.3: Fig.3 Flow chart of fuzzy self-tuning PID program Under unit step role, the simulation results of the fuzzy PID controller and traditional PID controller are shown in Fig.4, Fig.5 by MATLAB: 200 400 600 800 1000 1200 0 0.2 0.4 0.6 0.8 1 1.2 time(s) y Fig.4 Fuzzy-PID simulation curve 200 400 600 800 1000 1200 1400 1600 1800 2000 0.2 0.6 0.8 1 time(s) -0.2 0.4 0 Fig.5 Traditional PID simulation curve Simulation results show that the fuzzy PID control better than the traditional PID significantly in stability, speed, system overshoot.
Journal of North China Institute of Science and Technology.(2010),7 (2):59-63, In Chinese [2] Ruixue Zhang.The drying kiln wind speed testing and modeling and simulation based on the fluid dynamics.
Electronic Industry Press.(2010):33-50, In Chinese [5] YixingYang,DalianCui andAijunZhou.fuzzy adaptive PID controller and Simulink Simulation.

Navier–Stokes simulation is performed on a canard guided spinning projectile for different attack angles and circumferential position angles of canard over the Mach number range of 1.8–2.2.
Numerical simulations have the potential of greatly reducing design costs while providing a detailed understanding of the complex aerodynamics associated with each change.
Dual time stepping The “dual-time-stepping mode” was used to perform the transient flow simulations.
Canard configuration The grids used in all the simulations were structured meshes generated using ICEM (see Fig.6).
Computational Fluid Dynamics (CFD) modeling and analysis of the spinning projectile with fixed canard have been conducted to determine the longitudinal aerodynamic coefficients.

Numerical Investigation of Effect Pilot Injection on Combustion Noise and Exhaust Emission of Diesel Engine Tiemin Xuan a, Zhixia Heb , Zhaochen Jiang and Yi Yan School of Energy and Power Engineering, Jiangsu University, Zhenjiang 212013, China axuantiemin@163.com, bzxhe@ujs.edu.cn Keywords: diesel engine, fuel injection strategy, combustion noise, exhaust emission, numerical simulation Abstract.
Because of the symmetrical location of the injector at the center of the combustion chamber, the CFD calculations were performed with the mesh of 45ºCA sector meshes.
Calculations begin at Intake Valve Closure (218.5ºCA) and end at Exhaust Valve Opening (483ºCA) .The final mesh consists of a hexahedral dominated mesh shown as Fig. 1 Table 1 Engine specifications Engine type 1015 diesel engine Bore×stroke 132mm×145mm Compression Ratio 17 Connection rod length 262mm Engine speed 2100r/min Number of nozzle holes 8 Nozzle hole diameter 0.23mm Start of injection 350ºCA Fuel injected 180mg/cycle Injection pressure 90MPa Fig.1 The mesh of combustion chamber Fig.2 The comparison of pressure between experiment and simulation Calculating models.
The rate of pressure rise, temperature in cylinder, and Soot emission got from simulation for different injection strategies are given in Fig.3, Fig.4, Fig.5 respectively.
[3] Weisheng Zhu: Simulation of the Influence of Pilot Injection and Post Injection on the Combustion and Emission of Diesel Engine [D]. 2009.12 [4] Hyun Kyu Suh, Investigations of multiple injection strategies for the improvement of combustion and exhaust emissions characteristics in a low compression ratio (CR) engine.

The turbulent model is as described in [10].The k-ε turbulent model is used in the simulation, with VOF and Geo—Reconstruct method to trace the liquid-gas interface.
As shown in Figure 7, simulation results reveal that the bubble in the mixing chamber experienced a complex process of accelerating and expansion while flowing downstream to the exit.
Figure 7 Simulation result of bubblly flow Results show the flow pattern nearby the exit orifice.
(a) (b) Figure 8 VOF result near the exit Simulation also show that the time intervals between micro bubble generates can be less than10-5~10-6 s, and in the same order of time, the micro bubble pass through the exit orifice.
Turbulence Modeling for CFD.

Summary In this study, the refractory wear of blast furnace main trough has been numerically analyzed by CFD technology, resulting in the highlights below
Park, CFD simulation of condensing vapor bubble using VOF method, World Academy of Science, Engineering and Technology 36 (2009) 209-215

B6, Guangzhou College of South China University of Technology,Xuefu Road, Huadu District,Guangzhou City,Guangdong Prov, China 510800 yhua.zhong@gmail.com, zhongyh2005@163.com Keywords: Two-stroke Camshaft Piston top Energy saving Simulation; Abstract.
We take the cylinder head bottom as a mold,putting the paper clay above the cylinder, and, as a result, to make the originally combustion chamber soil model, then use to the shape of the piston top Solidworks modeling and through the inside of the Flow simulation Solidworks plugin to the Flow of air in cylinder is analyzed, and the built model related to size change, so in the machining process, the volume and quality of the proportion of the relationship with quality, change to reflect the change of volume filled, we use the electronic Ping day to fine grinding the quality of the piston to measure to ensure the quality of the piston entity and volume, refer with: Fig. 1, Fig. 2, Fig. 3, Fig. 4 Fig.1 The camshaft three dimensional figure Fig.2 Camshaft object Fig.3 Three dimensional simulation diagram Fig.4 Piston top physical Theory to calculate the energy analysis Hypothesis 4 stroke machine power stroke to check points after the piston can use inflation gas pressure can continue
Entity model and the computer simulation performance analysis The entity model of the assembly Considering lack of time and the influence of facility, the engine performance test can only be simulated by GT-POWER software.
Engine entity graph Fig.6Engine assembly drawing Two-stroke machine simulation of intake valve and exhaust valve top placing and making use of the piston effective POWER stroke based on the GT-POWER platform.
Aachen: Rheinische-Wesffalische Tech-nische Hochshule Aachen，2002 [2] Huang K D,Quang K V,Tseng K T.Study of recycling exhaust gas energy of hybrid pneumatic power system with CFD[J].Energy Conversion and Management,2009,50(5):1271-1278

. , Chang chun 130025, China; 2 State Key Lab. of Automotive Simulation and Control, Jilin Univ. , Chang Chun 130025, China a707193961@qq.com, blimingtiger@jlu.edu.cn, cxiaoye199046@126.com,d157178304@qq.com,e646358306@qq.com Key words: Numerical Simulation, Flow Distribution, Fitting Correlations Abstract：In this paper, the heat transfer rate of parallel flow heat exchanger was obtained in the condition of non-uniform flow distribution by 3D numerical simulation.
The concept of the second set of the tube was proposed by Anjun Jiao and Rui Zhang[7].The relation between S and Re in different forms of the tube bas been summarized.The uniformity of flow distribution has been improved by optimization of the forms.These researchs focused on the influence of structure changing.However, the non-uniform flow distribution on heat transfer efficiency was rarely involved.The correlation of the influence of non-uniform flow distribution on heat transfer efficiency was obtained by the comparative analysis of non-uniform flow distribution and heat transfer efficiency and regression calculation.The design consideration is accurately provided by the relation. 3D numerical simulation of the heat transfer rate of parallel flow heat exchanger Model and boundary conditions In this paper,two processes parallel flow heat exchanger has been researched.The first processes is made of 9 tubes,and the second is made of 12 tubes.Based on the CFD software for the flow of
the inside fluid of the heat exchanger ,condition on the heat transfer has been simulation analyzed by finite element method of mass conservation equation ,standard k - epsilon model,liquid R134a , 0.001003kg/（m·s）of inlet viscosity,1265kg/m3 of density,0.0093m3/s of the initial import flow,0.1m/s of flow velocity,pressure outlet and 190000Pa of gauge pressure.
The actual heat exchange capacity can be obtained by the 3D numerical simulation and the theory heat exchange capacity of parallel flow heat exchanger by 1D calculation .
Conclusion In this paper, the heat transfer rate of parallel flow heat exchanger was obtained in the condition of non-uniform flow distribution by 3D numerical simulation.The maximum theoretical heat transfer rate of parallel flow heat exchanger was obtained through 1D calculation.