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Simulation of the three-phase flow field in fan The most effective way of droplet atomization is to improve the relative velocity between the droplets and the surrounding air[4], And the expansion of the gas can also make the larger droplets broken.
The dust removal fan mainly uses the strong shear produced by the turbulence to droplets sprayed in low pressure to prompt the secondary fracture and the atomization of droplets, which can refine droplets. 2. 1 The establishment of geometric model and the determination of simulation parameters The diameters of entry, exit and impeller of radial-straight-vane wet fan are 200 mm, 200 mm and 520 mm respectively.
According to the Eq. 1and Eq. 2, the imported flow velocity is 20m/s and the outlet pressure is 400 pa, while the inlet turbulence kinetic energy and the dissipation rating are 1. 4 and 1. 2 respectively based on the method of Fujun Wang. 2. 2 Numerical simulation of internal flow field The velocity vector is revealed after the three-dimensional simulation of the flow field in the fan by fluent, which are shown in Fig. 4.
And then, the numerical simulation of gas - liquid - solid three-phase flow in the fan is carried under a certain dust concentration, which revealed the flow field distribution inside of the fan and the conclusion that the turbulence formed in fan has great effect on the secondary refining of droplets.
References [1] W D Griffiths,F Boysan.Computational fluid dynamics (CFD) and empirical modeling of the performance of a number of cyclone samplers[J].Aerosol Science,1996,27(2):281-304

Schematic diagram of Micromixer and inside flows Numerical simulation principle and CFD setting ANSYS-Fluent, a computational fluid dynamics software based on the finite element method, is adopt to investigate the mixing performance of the micromixer.
Various inlet velocities are also set for this simulation.
Re number with corresponding inlet velocity for numnerical simulation Fluid 1 Fluid 2 Re Inlet velocity(m/s) Re Inlet velocity(m/s) 0.01 0.000292 0.001 0.0056 0.1 0.00292 0.01 0.056 1 0.0292 0.1 0.56 7 0.204 1 5.6 10 0.292 20 0.584 50 1.459 100 2.919 150 4.378 Results and discussion Mixing performance of micromixer as demonstrated by mass fraction is shown in Fig. 2.
Conclusions In this paper, a chaotic triangle three dimensional micromixer has been designed and analyzed through numerical simulation.
The results of simulation show that the shortest and longest well mixing lengths are around 300um and 1250µm at the Re number of 0.01 and 50 for Fluid 1.

Direct Simulation Monte Carlo (DSMC) method is typical of this approach.
Since the size of model is small and the physical field is not complicated, we use the default UMFPACK solver in the film lubrication module in CFD.
Fig. 2 shows simulation results on the flat plate model.
Fig. 4 shows simulation results on the complex double-track model.
Fig.7 Contrast results of complex double-track model Summary Three simulation models were established in this study, including the flat plate model, double-track model and complex double-track model.

The simulation model of the power capsule Fig 5:Three-dimensional simulation model of power capsule Given the above test, we build the simulation model of the power capsule including the intake and exhaust grille, radiator, inlet volute, fan, outlet volute.
For the symmetrical arrangement of the fan, we use half model to do the simulation.
Table 3 shows the contrast between experiment’s results and the simulation’s.
Fig.6: Static nephogram of the profile of cooling system Fig.7: The velocity vector diagram of the profile of cooling system The thermal state simulation of the cooling system in the power capsule Given the validity of the simulation model, we make a thermal state simulation of the cooling system.
Evaluation of Cooling Air Duct Comprehensive Performance in Vehicle Based on CFD Analysis [J]. 2012，33（3）：50-53 [3] Bi X P, Liu X X, Zhao Y X, et al.

The cold junctions of thermal piles are put outside the cap to make it exactly at the room temperature, thus the device is very easy to calibrate and more accurate. (4) The chamber is filled with another kind of gas such as Xe or Ar to avoid the oxidizing effect produced by the commercial ones with carbon dioxide or air, and then the reliability as well as the life cycle of the heater can be increased. (5) By the results of simulation, one can see the traditional rectangular chamber can be replaced by a hemi-cylindrical one to extend both the operation range and sensitivity of the thermal convection accelerometer.
The third one is simulation and results discussion.
Simulation and Results Discussion In this section ESI-CFD+ software package is applied for simulation.
(3) By the results of simulation, one can see the traditional rectangular chamber can be replaced by a hemi-cylindrical one to extend both the operation range and sensitivity of the thermal convection accelerometer

Previous simulation of using oscillating flow to clean trenches has been verified and show excellent agreement with numerical and experimental results 1-3 .
Two geometries have been created and meshed for CFD calculations.
This phenomenon which results in the time effect in the removal process has been verified with the simulation.

There have been many publications in this general subject area, Most of which have focused on analyzing the forces and torques over the slipper, experimentally, analytically and via CFD[1-13].
Numerical simulation of a slipper model for water hydraulic pumps/ motors in mixed lubrication.
Numerical Simulation of Overturning Phenomenon of Axial Piston Pumps Slipper Pair.

The numerical simulation results of 12 typical fire scenarios prove that the boundary conditions of tunnel entrance exert a significant influence on the accuracy and reliability of the fire numerical simulation results in metro station.
At present the numerical simulation is the main fire risk assessment method of metro station, which uses the CFD (Computational Fluid Dynamics) program, such as FDS, Fluent, etc. to build the model, simulating the fire development and occupant evacuation, assessing the fire safety of metro station according to the simulation results [4-5].During the process of the numerical simulation, the boundary conditions of tunnel entrance have to be simplified to be fully close or open, due to the restriction of computing power and time of Computer Server.
Simulation Results and Discussion The simulation of fire smoke movement in metro station is carried out using FDS (Fire Dynamics Simulator), developed by NIST (National Institute of Standards and Technology).
The numerical simulation time of all the fire scenarios is 1200s.
The corresponding fire numerical simulation results are listed in table 2.

One may realize that it is possible to incorporate computational fluid dynamics (CFD) with Eq. (1).
The history of can be calculated by CFD software and thus a variational visibility range can be obtained.
More simulations are conducted for the four scenarios.
One finds that NOG in the simulation varies from 0 to 40.
Simulation of pedestrian dynamics using a two-dimensional cellular automata.

There are four known approaches used to solve Navier-Stokes equation: - solution of Reynolds – averaged Navier-Stokes equations (RANS) ; - direct numerical simulation (DNS), solution of Navier-Stokes unsteady-state equations without closing relations; - large eddy simulation (LES), which is based on Navier-Stokes unsteady-state equations performed with parameterization of sub grid scale eddies; - method called DES, which is a combinations of two methods : LES – in the zone of separated flow and RANS – in the zone of “smooth flow”.
The article describes influence of turbulence models on flow and temperature fields calculations in premises characterized by heat emission at test simulations.
Editorial: RANS modeling into a second century (2009) Special issue of International J. of CFD, Vol. 23, No. 4, pp. 291–293
Detached eddy simulation of flow around two wall-mounted cubes in tandem (2009) Int.
Large eddy simulation for compressible flows (2009) Springer, 276 p.