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The commercial CFD software ANSYS-FLUENT© was used to solve this numerical problem with the governing differential equations discretized by a control volume approach.
Simulations found that by increasing the nanoparticle volume fraction, heat transfer can be increased.
Hooman, Numerical simulation of natural convection and mixed convection of the nanofluid in a square cavity using Buongiorno model, Powder Technology, 268 (2014) 279-292

[5] Fujun Wang: Computational fluid dynamics analysis—Principle and application of CFD software (Tsinghua university Press, Beijing 2004) (In Chinese)
[6] Zhihua Wang: Numerical simulation and analysis of gas diffusion in confined space (Dalian university of technology press, Dalian 2009) (In Chinese).

The grid of calculation is the solving based on the flow field of numerical simulation, the quality of scheme for space discrete largely decides the accuracy of the flow field numerical simulation, and directly related to the success or not for the CFD simulation problems.
Considering the complex of the tip-blade flow field of wind turbine, this method controlling the variation gradient of grids near the blade wall can reduce false diffusion in the numerical simulation, ease the difficulty of the grid generation, and control the numbers of the grid, which can save the computing time efficiently and improve calculatingly accuracy.
Simulation Methods 1.
Selection of the Turbulence Model Use the Large eddy simulation method LES, and take the standard Smagorinsky [5] model as the small scale calculatingly grid model. 2.
Simulation Results and Analysis In accordance with the above set, through the calculation of the flow field, get the vorticity distribution of Z = 0 section of S series impeller, as shown in Figure 4; and get the radial velocity distribution of Z = 0 section of S series impeller, as shown in Figure 5; and get the axial velocity distribution of Z = 0 section of S series impeller, as shown in Figure 6.

All considerations presented in this paper are based on results of numerical simulations carried out for a high pressure fan impeller.
Numerical simulations were performed for the impeller of a high pressure fan designed for a rated pressure ratio of Π = 1.3.
Computational domain.The first simulation was performed for an outflow pressure of 25 000 Pa.
For the subsequent simulations, the outflow static pressure was increased or decreased, as appropriate, by 1 000 Pa.
As initial guess of each new simulation, the final solution obtained for the previous simulation was used.

CFD method, and erosion and cavitation interactive wear test is made on the rotary wear test-bed.
The test by Bao Chonggao etc. studies the performances of electrochemical corrosion and erosion wear of different materials in erosion wear process [1], Pang Youxia etc. analyze wear scar state and development law of sandy water flow around airfoil blade interface with turbulent boundary layer theory[2]；Wu Yulin etc make theoretical analysis and numerical computation on cavitation flow field of 3D turbulent flow of liquid-vapor two-phase flow in turbine runner[3]，Yang Minguan etc make numerical simulation and experimental study on cavitation characteristics in axial flow pump impeller [4]，Wang Jiadao etc study the effect of micro particles and their size on hydraulic machinery cavitation process[5]。
Simulation of cavitation flow in a francis turbine runner[J].
Numerical simulation and experimental study of cavitation in axial-flow pump impeller[J].
Fluent12 fluid analysis and engineering simulation[M].

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.

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

Numerical simulation of the aerodynamic micro air bearing is conducted to investigate the bearing load capacity.
The CAE part is composed of model import to GAMBIT software, grid mesh and boundary conditions setting, numerical simulation by FLUENT software, parameters optimization.
The micro-air journal bearing load capacity is analysed by numerical simulation by using the commercial software FLUENT.
The Computational Fluid Dynamics (CFD) of the air in the journal bearing is simulated in order to test the bearing load capacity.

There are several methods employed for the calculation of propeller static thrust which include experimental formula method, computational fluid dynamics numerical simulation and experiment.
The propeller performance CFD method[4] is developed from strip theory.
References [1] Ying Nie, Sheng Wang and Yanchu Yang: Computer Simulation Vol. 26 (2009), p.103-107 (In Chinese) [2] Hamilton Standard: Generalized Method of Propeller Performance Estimation, PDB 6101 (1967) [3] Peiqing Liu: Air Propeller Theory and Application (Press of BUAA, Beijing 2006) (In Chinese) [4] Dawei Wu, Hanbing Li and Shu Li: J.

Flutter Optimized Design for a Aircraft Horizontal Tail Base on Optimus Software Da-Qian ZHANG1,a*, Xiao-Dong TAN1,b, Zi-Lei ZHANG2,c and Xin-Ping FU1,d 1Key Laboratory of Liaoning Province for Composite Structural Analysis of Aircraft and Simulation, Shenyang Aerospace University, Shenyang, 110136, China 2 School of Economy and Management, Shenyang Aerospace University, Shenyang 110136, China azhangdaqian65@163.com, btan4362285@126.com, c 2534451919@qq.com, dyyfuxinping@163.com Keywords: Horizontal Tail, Scale Model, Flutter, Optimus, Optimized Design.
Cheng Mulin[1] analyzed the characteristics of the wing flutter using CFD Loosely coupled approach.
Numerical simulation of plane wing vibration in transonic flows ,J.Journalof Hydrodynamics,2004,19 (Supp1):871-876