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As it is only possible to add influence of the centrifugal force in a virtual case, we choose an elaborated computational fluid dynamics (cfd) model for our investigations.
This model can not be used this way in a cfd simulation as the wall speed boundary condition for the impeller uimp would introduce a wall normal velocity component into the flow field due to the blades, as shown in Fig. 1b.
The simulations were carried out for various pressure jumps.
Each simulation of the next higher pressure jump was initialized with the solution of the former lower pressure jump.Fig. 5: Polyhedral cfd mesh.

Increasing the number of trajectory points in this simulation process improves the accuracy of the results.
The commercial CFD software is used here to numerically solve the governing equations.
Therefore, it should be improved during the solid phase simulation using the instantaneous surface temperature.
Using the TPS on the nose in numerical simulation, the temperature time history are predicted.
The constant temperature boundary condition is used to predict the cold wall heat flux in flow field simulation.

It has become apparent that the result of simulation has been provided a theoretical basis for its optimization guiding to improvement.
This paper involved numerical simulation with the flow field in the spray nozzle to adopt CFD (Computational Fluid Dynamics) method.
The Results Analysis of Simulation 3.1 The factors Affect Convergence The studying team selected three typical size of model to simulate in the FLUENT simulation analysis.
In view of the above model, experiments show than the calculation of the model A was convergent after the 150 iterative steps. 3.2 The Simulation Results of Flow Field The simulation results series nephogram of model A, B and C’s main surface velocity were generated after the FLUENT ‘s calculation.
The Numerical Simulation Study of the Inner Flow in the Air-assisted Hydraulic Ultra-low Volume Sprayer Device.

In application of Computational Fluid Dynamics (CFD), dynamic and kinetic fields of two-phase flow in two equipments are researched.
Fig.3 3D graph of main fan diffuser of non baffle Fig.4 3D graph of main fan diffuser of incomplete closed baffles Numerical Simulation and Results Analysis Numerical Simulation and Results Analysis of Air-Phrase in Equipment Two physics models of two types of dust-controlling equipment are constructed and meshed by virtue of Gambit3.23.
Numerical simulations of two types of dust-controlling equipment are investigated by FLUENT6.3.
numerical simulations of two types of dust-controlling equipment are investigated.
The results of numerical simulation are shown in Table3.

And the simulation results of pressure drop were validated by the experimental data.
But it can be get by numerical simulation.
Numerical simulation The process of dense phase pneumatic conveying fly ash in taper pipeline was simulated on the FLUENT platform of the CFD software, by using an Euler-Euler two fluid model of dense gas-solid two phase flow based on the kinetic theory of gas and granular with the pipeline geometric parameters that the taper angle 8°and the diameter ratio being 80mm/65mm and 65mm/50mm respectively.
The Numerical simulation model can be given as following.
Conclusions By the experiments and the numerical simulation above, we can conclude the following results.

Predictive and descriptive models for hydraulic simulations and associated fish passage can provide a better understanding of the hydraulic forces fish confront in attempting to navigate these facilities.
Computer modeling such as computational fluid dynamics(CFD)--a three-dimensional numerical computer modeling technique--is often used by engineers to obtain detailed flow field characteristics, such as water velocities and pressures, within a hydraulic system.
CFD is an economical and fast way to determine flow behavior in the hydraulic system, and complements the use of traditional hydraulic physical models [20].
Hydraulic information from the CFD models could be used to design fish passage systems like prototype surface collectors and to investigate potential linkages between project operations.

This approach was applied separately wind tunnel test and numerical simulation, to obtain six aerodynamic coefficients of the corresponding heavy duty truck model, and the numerical simulation method was proved to be true by comparative analysis.
The model used in simulation is the same with that in the wind tunnel test, and their boundary conditions are same as well.
CFD (blue) in Fig.3 refers to the result of simulation, while test (red) refers to the results of wind tunnel test.
We can find that there is little difference between the results of the simulation and wind tunnel test whose relative errors are within 5%, which has verified the validity of the numerical simulation.
As a result, the numerical simulation method can be used in the crosswind aerodynamics research of the heavy duty truck.

Through simulation or theoretical studying, the jet flow field can be predicted.
Baik et al had analyzed the gas dynamic behaviors in a high velocity oxygen-fuel thermal spray gun through a nozzle using CFD analysis method [4].
In this simulation, the effects of contraction angle of nozzles and of the distance between nozzles on the water spray flow field are analyzed.
After simulation computing, the results of curve graph of water flow pressure field on the line are gotten as shown in Figure 8.
Fluent software is used to simulation the water flow velocity field and pressure field.

Among these runs, the aligned one is chosen as the general posture for the transient simulation.
The general posture with an inlet water velocity of 2 m/s and a wall roughness height of zero is taken as the reference case for the comparison of the simulation results.
The simulation results are shown in the following figures.
The effects of swimsuit roughness play a more important role in the transient modeling than that in the steady-state simulation.
Turbulence model choice for the calculation of drag forces when using the CFD method.

The DES unsteady simulation based on S-A model was applied to analyze the noise in the flow domains which are consist of the volute and the impeller passage in the paper.
Yang Liu [6] predicted the pressure fluctuation of axial pump and centrifugal pump operating at multiple conditions through the method of large eddy simulation, concluding the characteristics of time and frequency domain at monitoring point.
This paper based on CFD software (Fluent) and sound vibration analysis software (SYSNOISE), aimed at research difficulties of internal flow noise for the model centrifugal pump, via the data interface between Fluent and SYSNOISE, and used the CFD and acoustic solver coupling method to solve the internal flow noise in centrifugal pump.
Fig. 4 shows the vortex distribution and the tongue of partial enlargement on three different working conditions of unsteady simulation of initial moment (t=0).