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Very recently, researchers carried out the numerical simulation cases including seakeeping tests and reported the results on the Gothenburg 2010 CFD Workshop.
It can be seen from Fig.2 that the simulation results are well agree with the target results, and the NWT can offer high precision wave environment for the seakeeping simulation.
The transfer functions obtained by CFD are evident fine than that calculated by strip theory method.
The strip theory method has difficult to treat the nonlinear motion; by contrast, the CFD method has the advantage to cope with the nonlinear motion.
Applications of the SWENSE Method to seakeeping simulations in irregular waves.

Numerical simulation on air flow field of tangential longitudinal axial combine harvester Li Yaoming1,a，Li Fang2,b 1,Jiangsu University institute of agriculture engineering, Zhenjiang 212013, China 2,Jiangsu University institute of agriculture engineering, Zhenjiang 212013, China ayml@ujs.edu.cn,blifang_smart@163.com Key words: tangential longitudinal axial, cleaning device, air flow distribution, numerical simulation Abstract: With the use and popularization of the tangential longitudinal axial combine harvester,the cleaning device of high loss rate and impurity rate continuously emerging.In order to analyses the reason of cleaning performance is low,the study for airflow field distribution of the tangential-longitudinal axial combine harvester has been carried out.Based on homogenization when Reynold continuous equation and navier-stokes equation and the renormalization group (RNG) kappa epsilon turbulence model predominate constitute a closed equations,Using CFD simulation
This paper in 4LZ-850 type tangential longitudinal axial combine harvester as the research object,Through the modeling of physical dimensions,studied the cleaning shoe air flow field distribution by CFD software.
For cleaning shoe air flow field simulation of RNG kappa epsilon turbulence model predominate.
Fig.1 Diagram of cleaning chamber cavity CFD calculation domain structure Fig.2 Diagram of cleaning chamber cavity Grid computing domain After build the 3D model ,then import into Fluent before processing software ICEM mesh.
But the simulation results shows that the airflow field of the cleaning shoe is symmetry in the width.

A finite element calculating model of CFD was established coupled radiation and natural convection to accurately predict lamp surface temperatures.
Simulation results were consistent with the experimental data, and the validity of the computational model was confirmed.
Computational Fluid Dynamics (CFD) is a computational technology with which we can analyze the velocity of flow and temperature inside the lamp [2].
Thermocouples were used in test, and we compared the simulation data and experimental results.
In the new simulation, and .

The mainstream methods include CFD simulation, model test and field research.
Then model test or field research can be taken to verify the accuracy of CFD simulation.
Therefore, the result of CFD simulation is of great value for the post-analysis.
In 2006, John Halkyard proposed some suggestions about the meshing and selection of turbulence model in CFD simulation under large Reynolds number, by comparing the results from model test and CFD simulation. [1] In 2005, Kallinderis Yannis studied the stability, time step and accuracy of CFD simulation under high Reynolds number, by CFD simulation considering the fluid-structure interaction.
The simulations are as below.

Wind tunnel and numerical simulations have shown that the rocket plume can significantly influence the aerodynamic behavior of the ejection seat especially at high angle-of-attack.
Local Grid Refinement The accurate simulation of the aerodynamic effects of rocket plumes is based upon an accurate prediction of the plume shape and surface pressure near the plume base.
Comparison of Measured and Computed Nozzle Thrust Profiles In Fig. 6,the thrust versus pintle position profiles predicted by the series of CFD solutions is compared to the profiles derived from the Aerojet test data.The equilibrium and frozen chemistry simulations predict almost identical thrust profiles,and both compare well with the test data.Both the CFD and test results produce a nearly linearly thrust profiles as a function of pintle position.At the lower thrust settings,the CFD simulations tend to over predict the nozzle thrust.This phenomenon was also reported in the Aerojet analysis[13]and was attributed to thermal expansion and ablation of the nozzle throat.
Acknowledgments The authors of this report would like to thank Dr.Anatha Krishnan of CFERC for his support in adapting CFD-ACE to perform equilibrium simulations of ejection seat rocket plumes,and Mr.Matt Thomas for providing information on the composition and properties of solid propellants.The authors would also like to thank Mr.Joe Morris and Mr.Bill Barnette of Aerojet for their full cooperation in providing detailed geometry and test data on the PEPS system.
[9]Habchi, S.D. and Rock, S.G., "CFD Analysis ofFourth Generation Ejection Seat with StagnationFences," CFDRC Report #4437/1, 1996.

In CFD, hemodynamic studies employed Newtonian[3,7,8,9] and non-Newtonian models[10].
The flow of blood in aneurysm geometry is simulated using CFD approach.
The parameters for simulation is summerised in Table 1.
Palombo., CFD Modelling of Blood Flow in Portal Vein Hypertension With and Without Thrombosis.
Conference on CFD in the Minerals and Process Industries. 2003

As the developments of CFD technologies, Qin Hongxin etc. [7] calculated the meter factor by Finite Element Analysis method.
In equation (4) , The value of Fβ is determined by magnitude and direction of the outer load ,for rolling ball bear, it equals the radial load, and can be calculated by the CFD results.
That means that in the CFD process, we should consider the following two aspects to realize simulation of the unsteady transient: 1.
Additional source forces should be added during the simulation process.
Fig. 3 The relationship between the torque and the rotating speed Fig.4 showed the meter factor comparison between the calibration experiment and CFD simulation.

With simulations, the suction process of dusts was investigated using commercial CFD program Fluent 6.3.
The equations described above were solved numerically by using finite volume based Fluent CFD code.
With simulations, the airflow characteristics and dusts removal efficiency of a pickup head were evaluated for different pressure drops.
Xu: Journal of System simulation.
Zeng: Journal of System simulation.

CFD method is efficient and cost saving, and besides, it can simulate the condition and obtain the data which experiment cannot [6].
With CFD methods we can quickly obtain the force that fluid impact on the blunt and the total pressure distribution in the field.
CFD used in simulation of automobile external flow and pipe flow has developed ripely and is reliable, so numerical simulation is used to probe the relationship between the total pressure distribution and drag [8].
Fig. 1 Blunt body and field of case1 Fig. 2 Volume mesh in symmetry plane In this paper, SST k-ω turbulence model is selected in the CFD simulation.
Summary In the post-processing of CFD simulation, the total pressure equals to 0 isobaric surface can be used to qualitative analysis the structure of the flow field.

Mixer geometries have also been optimised with the use of CFD, for instance with respect to the twist angle of solid elements of the Kenics mixer [4].
In our simulations, an entrance and exit section of 0.05 meters is added to the pipe to assure well-developed flow into and out of the mixer region.
The flow during the simulations was assumed to be three dimensional, steady and incompressible.
(1) Comparison with literature data In order to verify the validity of the proposed correlation obtained from CFD simulations, we compared it with several correlations available in the literature.
Conclusions It can be conclude from the CFD simulation that the pressure drop increase with the increase of element number and the pressure drop per element is independent of element number.