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The complex geometry of landing gear brings a lot of difficulties in numerical simulation.
CFD combined with FW-H acoustic analogy hybrid approach is currently the most commonly used numerical solution method in aerodynamic noise studies.
Compared with large eddy simulation or other methods, computational efficiency of NLAS is higher.
Detached-eddy simulations over a simplified landing gear[J].
Simulation and experiment on aeroacoustic noise of aircraft landing gear[J].

Characterization of graphitic foams has been conducted using Computational Fluid Dynamics (CFD).
The influence of turbulence on the momentum and energy balances is modelled herein using a Large Eddy Simulation (LES) model.
All simulations were performed on a grid comprised of hexahedral volumes.
Summary Large Eddy Simulation has been used to model the turbulent flow and heat transfer in porous graphitic foam.
Sagaut, in: Large Eddy Simulation for Incompressible Flows, Springer, Berlin (2006)

The computer simulations were validated by the analytical solution results.
The CFD software is used for the numerical simulation, in which the Finite Volume method is adopted for the governing equations discretization; The SIMPLE method is applied to deal with the linkage between pressure and velocities.
And the local fRe obtained from simulation was compared with analytical solution showed by Yilmaz[6], which shows excellent agreement, as depicted in Fig.2
The Nusselt value obtained from simulation agreed with the theoretical value showed by Shah[7].
Fig.3 Effect of Reynolds number on the fRe Fig.4 Local Nusselt numbers Conclusions In this work, numerical simulation for fluid flow and heat transfer in the rectangular microchannel cooling passages are conducted.

The simulation model of blades in PECM.
Coupling Simulation Coupling Method.
Material and Simulation Parameters．In this simulation, the materials of the cathode and anode are Ti-6Al-4V and electrolyte is NaNO3 solution.
Simulation parameters.
Turbulence Modeling for CFD. 2nd ed.

Two-dimensional numerical simulation was conducted by VOF model and CSF model based on the test geometrical model.
Numerical simulation The 2-dimensional unsteady simulation on the flow phenomenon of deposited water displaced by laminar flowing oil in hilly terrain tube shown in Fig. 1 was performed according to the computational fluid dynamics (CFD) theory by FLUENT software which is based on the finite volume method.
A no-slip boundary condition was imposed at the tube wall for all simulations.
To further compare the simulations with the theoretical predictions, the critical condition also is predicted by water plug model [9].
Therefore, the simulations by VOF and CSF model could describe the mechanism of oil-dragging-water system reasonablely.

Simulation results provides a good technical support for the optimization design of three-phase hydrocyclone structure.
According to the gas-liquid-solid three-phase separation (degassing and degritting integration separator) physical model and combining with numerical simulation analysis, we have furthered the structure optimization design.
Flow Field Analysis and Structure Optimization of Three-phase Separation Hydrocyclone Based on CFD[J].

Performance Analysis of Bionic Propulsion Device above Water in Different Parameters Xianghua BAI1, a, Fenghe TAO2, b and Jiangang LV3, c 1,2,3Machine Engineering College, Shijiazhuang Hebei, 050003, China baixianghua@163.com Keywords: Amphibious vehicle; Bionic propulsion; Angle; Immerged in water; Simulation Abstract: This paper mainly researched on hydrodynamics performance of a wheel-blade bionic propulsion device designed based on the mechanism of a basilisk lizard treading water, when immerged in water and in different angles.
Fig.1 The theory analysis of basilisk lizard Fig.2 The wheel-blade bionic propulsion treading water device immerged in water Simulation and Analysis Modeling and Simulation enactment.
In the simulation，adopted RNG onflow model[3], for this model has perfect performance to solve the hydrodynamic problem, Applied UDF to define the angle velocity of the bionic impeller as , and then initialized up-half part of control box as air and the other was liquid.
Through the simulation and analysis hydrodynamics performance of the bionic propulsion device immerged in water and in different angles, summarized the rules and features of the revolving movement for bionic impeller and established the groundwork of optimizing the design of the bionic propulsion device further.
[3] Fujun Wang:The Theory and Application of CFD Software(Tsinghua University Press, Beijing 2004),in Chinese

Literature Review A Notable number of research studies investigate the effect of wake interactions between turbines on power production of wind farm .These studies developed a mathematical programming models that maximize the power production while minimize wake effect based on numerical approaches that can split on two approaches :Heuristic methods for optimization and computational fluids dynamic (CFD) for investigation and analysis.
The CFD results proved that the output power of downstream turbines increase as the separation distance rises.
Generally wind velocity deficit is calculated using analytical models which are simple to be solved analytically or otherwise considered computational models based on CFD method [12,22].
Xie, C .Archer, Self similarity and turbulence characteristics of wind turbine wakes via large ddy simulation, W.Energy .18.10 (2015) 1815-1838
Mikkelsen , Comparison of engineering wake models with CFD simulations.

Bhuiyan et al. [11] caried out three-dimensional CFD simulations to investigate heat transfer and fluid flow characteristics of a four-row plain fin-and-tube heat exchanger using the Commercial Computational Fluid Dynamics Code ANSYS CFX 12.0.
Reasonable agreement was found between the simulations and experimental data.
The results were compared with a CFD model that assumed the heat pipes were solid rods with a constant conductivity.
Numerical simulation results indicate that an optimal perforation design can be obtained to realize a maximum increase in the j factor.
Effects of geometric parameters for wavy finned-tube heat exchanger in turbulent flow: A CFD modeling (Article), Frontiers in Heat and Mass Transfer, Volume 6, Issue 1, pp 1-11

By comparing the calculated results of numerical simulation and semi-empirical theoretical equation, the numerical simulation is proved feasible in oil film state analysis parameter prediction, which can overcome the deficiency of single model and get good effect.
Numerical Simulation Model of the Single Oil Pad.
Three-dimensional geometry model of the oil film is produced by software UG, then the model is introduced into the pre-processor ICEM CFD to generate grid.
Critical flow and critical speed were determined by numerical simulation, it provides a theoretical basis of the temperature field and thermal deformation field calculation.
Zhang: Simulation and Scientific Computing (ICSC 08), pp. 675-679