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S.Som[5] and the others proposed a new primary atomization model that is KH-ACT model which considered influence of aerodynamic effects, turbulent and cavitation and numerical simulation results were closer to those from the test;Berg[6] used three-dimension model to simulation two-phase flow in nozzles and coupled the data at the nozzle outlet from simulations with primary atomization model considering of cavitation.At present, study of primary atomization is far from enough,with both experimental way and numerical simulation.In this paper,the turbulence and cavitation in nozzle flow were coupled to simulate spray and different primary atomization model were analyized and evaluated though numerical simulation with them and then influence factors on primary atomization were analyized.
Fig. 1 Grid calculation Initial and boundary conditions of Spray simulation are as table 1: Table 1 Parameter sign unit number Cylinder pressure P Pa 374755 Cylinder sir density kg /m3 1.19 Cylinder temperature T K 340.6 Turbulence kinetic energy TKE m 2/s2 30 Turbulence length scales TLS m 0.0075 Start crank angle ° 360 End crank angle ° 397 Nozzle diameter D m 1.95×10-4 Injection mass M kg 2.76×10-5 Three-dimension CFD model of cavitating and turbulent flow in the nozzle There are six symmetrical holes of the nozzle and one half of the hole was selected for simulation,so the sector zone of 30 degree of the nozzle was selected for generating grid,as shown in Fig.2.
In the future the following several aspects of primary atomization will be paid more attention to :(1) advanced visualization experiment devices must be used to get the detailed structure of intalt liquid core in primary atomization.(2) new precise primary break-up model which consider aerodynamic effects, turbulence and cavitation must be setup and be input to CFD spray models for getting more actual spray simulation.
Coupled simulations of nozzle flow, primary fuel jet break-up and spray Formation, J.
Vertical porous nozzle internal hole two phase flow of three dimensional numerical simulation analysis [J ] .

The basic experiment and detailed simulations are carried out to study the aerodynamic characteristics of projectile with deflectable nose.
Further simulations show that the influence of mach number and deflectable angle on drag, lift, pitching moment and flight trajectory.
With a vorticity confinement method, Vaughn[5] performed CFD solutions to validate the experimental data of Landers.
Further simulation can be done based on these parameters.
Gao: Computer Simulation Vol. 25 (2008), p. 23-26 [3] J.H.

The resistance of the three hulls is predicted using the CFD software FLOW-3D, at the same time, the midship section modulus of the three hulls is calculated in this paper.
Numerical Simulation of Total Resistance The CFD software FLOW-3D was employed to calculate the total resistance [3].
A series of speeds has been chosen to test the accuracy of the software by Dazheng Wang; It showed that the simulation method that FLOW-3D is employed to simulation the fluid field of the ship and predict resistance of it can replace part of the model test to save the costs, which has a good agreement between the simulation results and experiment data, especially the trends of resistance curves of the simulation results and experiment data, are basically consistent with each other [4].
According to tests analysis, 0.3m grid size and the computation domain x=60, y=31, z=12 were setup for the following simulation cases to ensure computation accuracy and save computing cost.

A preliminary study of Computational Fluid Dynamics (CFD) on the effect of high Reynolds numbers in the cavity has been carried out.
Streamline comparison between experiment [3] (left) and simulation (right) Results and Discussions Different flow patterns were identified in every simulation conducted in this study.
There were two vortices occurred in the cavity of each simulation with high Reynolds number Re=10000 as shown in Fig 3.
The simulation of the flow inside the cavity also calculated the pressure along the top layer of the cavity and tabulated in the graph.
Shaughnessy, CFD Simulation of contaminant decay for high reynolds flow in a controlled environment, Annals of Occupational Hygiene 54 (1) (2010) 88–99

CFD simulation is done using the ANSYS Fluent with pressure inlet and pressure outlet boundary conditions and k-ε turbulence model.
The resulting 3D models is then meshed and simulated by using CFD software.
CFD simulation results show that hydraulic efficiency is only about 84-85% [3, 4].
Fig. 26 Mesh Analysis CFD Simulation CFD Simulation is carried on ANSYS Fluent [12] with SRF (Single Reference Frame) scheme, which means the fluid is set in motion instead of the runner.
The simulation process can now be started.

The Simulation and Experiment Study on the Gas Flow in the No-loaded and Cold Vacuum High-pressure Gas Quenching Furnace Zhijian Wang 1,a and Xiaofeng Shang 1,b 1School of Mechanical and Electrical Engineering, Shenyang Aerospace University, Shenyang Liaoning, China, 110136 awangzhijian1974@sina.com, bxfshang@vip.sohu.com Keywords: Vacuum high-pressure gas quenching, Hot wire anemometer, CFD, Flow field, Pressure field.
Hot wire anemometer is used to measure the speeds of some feature points, on the one hand to provide boundary conditions for the numerical simulation, and on the other hand to compare with the numerical simulation results.
Computational Fluid Dynamics (CFD) is an important method to study the complex gas flow during high pressure gas quenching.
Fig. 5 Comparison of computer simulation with Fig. 6 Comparison of computer simulation with experimental results (X=0,Y=0.4m) experimental results (X=0, Z=0.29m) In order to compare experimental results and simulation results, we take different positions to make speed curves.
Fig. 7 Comparison of computer simulation with Fig. 8 Comparison of computer simulation with experimental results (X=0, Z=0.525m) experimental results (X=0, Z=-0.525m) Comparing the simulation results with the measured results, we can find they are basically consistent, and the error is within 10%, which proves that numerical simulation of flow field calculation and prediction is feasible and the results are reliable in high pressure gas quenching device.

The simulation with CFD software Fluent and analysis for its internal temperature field was done, and then make a comparison between Shuttle-type high-temperature, high-pressure, anti-erosion special valve and swing check valve, and it can be concluded that the former doesn't exist local thermal stress concentration.
Simulation condition is DN200, PN20MPa, inlet temperature is 360 ℃, flow is 300m3 / h, fluid medium is water and steam.
Model of simplification Numerical simulation is implemented with CFD software Fluent.
Fig3, Fig4 and Fig5 show the results of simulation.
Temperature field distribution of 100% opening It can reach the flowing conclusions from the last simulation section.

More recently, CFD has been applied to the design of internal combustion engines, combustion chambers of gas turbines and furnaces [6][7].
Furthermore, motor vehicle manufacturers now routinely predict drag forces, under-bonnet airflows and the in-car environment with CFD [8],[9].
Numerical simulations of lid-driven in square and deep cavities are carried out.
Doolen, “Simulation of cavity flow by the lattice Boltzmann method,” J.
Rogg, “Lattice Boltzmann simulation of lid-driven flow in deep cavities,” Comp.

In this paper, a simulation method was realized to predict aeroelastic response and characteristic parameters of wing structure.
Coupled aeroelastic solution procedures used strongly coupled algorithms which contained sufficient interaction between Computational Fluid Dynamics (CFD) and Computational Structural Dynamics (CSD) such as the stability of the system was at least equal to that of the least stable code [1].
Therefore, the System Coupling/ANSYS Workbench was used to transfer aerodynamic pressure loads from the CFD grid points to the CSD grid points and vice versa, which ensured a conservative transfer of energy between the two systems [3].
To determine the optimum time interval size, it was reduced until the aeroelastic simulation did not change by further decrease in the interval size [3].
The flow field was solved by using a commercial CFD solver, Fluent.

CFD is used to do numerical simulations of multiphase flow and reaction process [1].
Li Xiang [5] did research on the particle movement through CFD-DEM numerical simulations, which indicated that bubble become larger with the implication of vibration, but the vibration amplitude and frequency has no effect on the number of bubbles generated.
In this paper, CFD technology is used to improve simulation model of VFB; and research how aperture ratio of distributor effects on fluidization characteristics under the conditions of cold model, which in order to determine the index of fluidization quality and appropriate bed pressure drop ratio for the lignite drying process. 2 Numerical simulation method 2.1 Fundamental equations Particle phase is considered as two model fluid in the Euler-Euler model, which makes it has the same form with the gas equation, and that is similar to the single phase flow equation.
The simulation shows that bubbles form when solid fraction is less than 0.2.
Fluidization technology and computer simulation [J], Computers and Applied Chemistry, 2008, 25(9): 1047-1050