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Introduction Changes of air-flow field depends on a number of factors, as the form of superstructure, the change of the relative wind direction and speed[1], There are a lot of experts who have studied at home, such as Jiang Zhi-fang in Chinese ships research center and Lu Chao do a lot of research work in this area, at the mean time they achieve good effect, so that can prove CFD method can accurately predict the ship’s air-flow field, but the analysis of the change of the movement of air-flow field in the wave is still in the preliminary stage at present.
In this paper, we will use of FLUENT software to calculate the movement of air through the ship from the deck of the current field, we will take the Nimitz Class Aircraft Carrier in the United States for reference, we set up with the original ship 1:1 model for numerical simulation analysis, emphatically analyzed the wind condition when the ship motion in waves at the 3 degrees and equilibrium position, the effect on the flow field on the deck and through the numerical analysis of the results and the image display airflow field under three kinds of motion characteristics are compared and evaluated.
The Numerical Simulation The relative wind speed in air inlet is V=15.43m/s，（It equal to the speed of 30 knots），set the wavelength of the waves=150m， height A=3.5m the size of hull pitch is 2.5 degrees，time step is 0.005 s，the iterative calculation of 15000 time steps，Every 500 time step to save time.
Pitch angle of degree simulation analysis.
[2] Qu Fei, Lu Chao and Jiang Zhi-fang,CFD Numerical simulation of ship airwake, Chinese Journal of Ship Research, vol. 4., pp.23–27,October 2009

Preliminary studies have been conducted on the fluid flow and heat transfer characteristics of a parallel plate heat sink through the CFD modelling and simulations to determine the optimal heat sink design [4].
(1) (5) (2) (6) (3) (7) (4) Results and Discussion In order to minimize the material cost and fabrication time, the hot sink was initially designed and evaluated by using Finite Element (FE) simulation.
The hot sink specification was then analysed with two heating sources of 150 oC in the simulation based on the theoretical calculation from equation 4 to 7.
[4] R Arularasan, R Velraj: CFD analysis in a heat sink for cooling of electronic devices, Int.

The fluid used in the simulation is air, at temperatures of 300 to 700 K, and is treated to be incompressible, at the inlet face of the tube with an inlet velocity of 0.264 m/s.
Fig.2.Temperature and Fig.3 Velocity conturesCFD profile Conclusions Flow fields inside a circular tube have been studied numerically using a CFD code to optimize the fin shape for batter heat transfer enhancement.
The CFD approach with schemes used in this study is to simulate the flow pattern inside the circular tube which is attached with fin internally.
Sarangi, Influence of Porosity on the Performance of a Pulse Tube Refrigerator: A CFD Study.

Based on the numerical simulation of the three-dimensional flow field in blade channel,the aerodynamic loadand the stressstrain of the blade can be more accurately obtained.
Pressure distributions around the surfaces of main blade and splitter blade are calculated through CFX.Then the data will be delivered to the Static Structure module in ANSYS/ workbench using the interface between CFX and ANSYS.Load data is transferred from CFD mesh nodes to an ANSYS structure mesh nodes;the mapped forces on the blades surface are almost equal to the computed forces from CFD results.
What’s more,Load Transfer Summary shows thatabout 98% of mechanical nodes were mapped to the CFD surface, and the remaining nodes are mapped to the closest edge or node.

The other two compartments are always safe during the simulation time.
Simulation Method Large eddy simulation is the default mode of FDS and chosen as the simulation method in this paper.
In views of temperature, other compartments are always safe until the end of the simulation.
In views of visibility, other compartments are always safe until the end of the simulation.
"CFD simulation and assessment of life safety in a subway train fire."

The results show that: (1)Using the sense organ’s symmetry characteristic, a half model is built first, which is convenient for modelling and observing the simulation results;(2) Gridding should be meshed more densely where fluid grads is large, which is helpful of saving simulation time and improving precision.
The FLOTRAN CFD analysis function of ANSYS program is chosen, because it is an advanced tool used to analysis the two and three dimensional flowing fields [2].
Considering the factors above, the whole volume is divided into 204805 units, which makes simulation simple and fast, as shown in Fig.4.
According to the finite element simulation results, the airflow velocity of half model almost reduces to 50% of the whole model.
Wang, “Numerical simulation and practice on ANSYS,” M.

It can be used as verification of analyze or numerical simulation.
The numerical simulation is developed with computer calculate power, and it’s widely used in CFD area.
There are plenty of related test and simulation.
The result from fluid field is just the boundary conditions of structure simulation.
Therefore, by CFD simulation under multiple conditions, distribution and changing feature are got and can be analyzed to summary to a typical load model.

The Numerical Simulating Research about the Pulse Cleaning Process of Bag Filter Zhihua Li1,a, Jianfeng Liu1,b, lei Jiao1,c, Zhou Li1,d and Zongxiang Peng1,e 1Shandong Provincial Key Laboratory of Polymer Material Advanced Manufacturing Technology (Mechanical and Electrical Engineering School of Qingdao University of Science & Technology), Qingdao, China alizh@mesnac.com, bljf_87@126.com, cs0505010327@163.com, dlizhou@mesnac.com, exiangzi_213@126.com Key words: air nozzle; filtering bag; numerical simulation; pulse cleaning Abstract: With the computational fluid dynamics (usually being called “computational fluid dynamics” for CFD) method, the velocity field between the air nozzle and the filtering bag and the velocity distribution inside the filtering bag are computed when changing the distance between the air nozzle and the filtering bag.
According to the simulation result, this article has analyzed the influence of different distances between the air nozzle and the filtering bag and different injecting times on the dust-cleaning effect, and supplied theoretical basis to design the optimal pulse bag filter.
The simulation indicates that 200mm is the best distance
(2) In the process of cleaning, the filtering bag shakes in waves from the top of the bag to the bottom, which is consistent with the actual situation, so that the injection inside the filtering bag can be analyzed with numerical simulation
The simulation indicates that the optimal injecting time is 120ms.

Numerical Simulation of a Shell-and-tube Heat Exchanger with Special Form Helical Baffles Can Zheng1, a, Fei Wang1,b and Yonggang Lei1,c 1Taiyuan University of Technology, Taiyuan 030024,China aCarter153@126.com, bwfwfsir@126.com, c yongganglei@yahoo.cn Keywords: Helical baffle, Heat exchanger, Numerical simulation, Air fluid Abstract.
Comparative study, through numerical simulation, was undertook between the new helical baffles heat exchanger and segmental baffle board heat exchanger in shell side flow and heat exchange characteristics.
After models of both the new type helical baffles heat exchanger and segmental baffles heat exchanger with same geometric structure were set up ,numerical simulation was undertook in its shell side flow and heat exchange characteristic by CFD method[5].
The results of numerical simulation Flow field analysis.
(a) (b) Fig.5: (a) Pressure drop and heat transfer rate versus mass flow rate (b) Heat transfer rate under unit pressure drop versus mass flow rate Conclusion In this paper, the shell side of helical baffles heat exchangers on heat transfer characteristics analysis with numerical simulation method, comparing with segmental baffle board heat exchangers which have the same geometry structure.

aamois@teiser.gr, bdim@teiser.gr Keywords: Casting Simulation, mesh, FEA, Hyperworks.
The Solution of Simulations The subject of use of simulations does not only concern the software developing companies but also the manufacturers of the complex parts.
Many Simulation codes have been written for helping engineers to understand better the casting process.
Propeller has many curve surfaces that are developed by using CFD codes, these surfaces are very important for the best performance of the propeller.
The results retrieved from the simulations show that the use of Casting simulation creates better products.