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One of the alternative method in CFD is the lattice Boltzmann method.
Unlike the traditional CFD methods, which solve the conservation equations of macroscopic properties (i.e.
The excellent match of the present results with the present study demonstrate it validity for the simulation.
Dass, Simulation of Incompressible flows in two-sided lid-driven square cavities.
Part I – FDM, CFD Letters. 2 (2010) 1-12

While adhesion of airborne sea salt particles to bridge structures are simulated locally by a CFD analysis, the large scale analysis yields a boundary conditions of the local analysis and is given by a part of a mesoscale meteorological analysis.
In the local analysis (representative length scale is about 102m), adhesion of airborne particles is simulated by two phase flow analysis using computational fluid dynamics (CFD) (See [1,2] for details).
Fig. 3 illustrates an example of the simulation of adhesion of airborne particles to a bridge girder [1].　　
Therefore, WRF/Chem can provide reasonable boundary and initial conditions for elaborate local analyses based on CFD in these areas.
Goto, (2008) Numerical simulation of sea salt particulate matter adhesion on bridge surfaces by two-phase flow analysis, J.

In this study, numerical simulations of the two-dimension hill over smooth and roof surface have been done using three different turbulence model :standard k ε− model and other revised models ,and the simulation results have been prepared with wind tunnel experiments ,in order to obtain the best turbulence model .
Currently,the location of wind power plant or wind turbine is mostly selected by using standard linear model software WAsP.Now more and more designers of wind power plant find that WAsP software is not suitable for wind power plant over complex terrain.So calculated fluid dynamics(CFD)begins gradually to be applied in the research of complex wind power plant.CFD simulation can fully consider the impact of terrain,roughness and barrier on orographic wind,establish numerical wind tunnel test,and calculate the flow field of orographic wind.
This model is given by Ishihara and others in 2001 when they made wind tunnel test,figure 1 describes the length and the heigth of the hill clearly,then compares the result of the simulation with this test.The mesh generation is showm in figure 1(b),the mesh of the surface layer of the hill is refined.
2 shows the results abtained from the simulation of three models on the hill with smooth surface,figure 2 (a) expresses the distribution of standardized turbulent kinetic energy, (b) represents the distribution of the average wind speed vector,and part 1,2,3 are respectively corresponding to standard k ε− model,RNG k ε− model and realizable k ε− model;The value of standard k ε− model is much larger than that of RGN k ε− model and realizable k ε− model in the distribution of standardized turbulent kinetic energy 2 Hk u in the position of the hill top compared results of three models.
The simulated results of realizable kε− model Fig. 3 shows the results abtained from the simulation of three models on the hill with rough surface,obviously, standardized turbulent kinetic energy 2 Hk u is in the position of the hill top,and the value of standard k ε− model is much larger than that of RNG k ε− model and realizable k ε− model;In the flow region in front of the hill,when 11.25 / 0X H − < < ,the standardized value of k abtained from RNG k ε− model is more close to testing value,the standard k ε− model and the realizable k ε− model both overestimate the value of k in this region,but after pasing the hill top,RNG k ε− model underestimates the value of k,however the value of realizable k ε− model and test is most approach.

Along with the development of fluid dynamics research, it is feasible and has obvious advantages to adopt simulation study with the CFD simulation software for attrition of sewage pump.
Model parameter of centrifugal sewage pump The paper took type of 50W15 centrifugal sewage pumps as research object for simulation.
Simulation results and analysis The simulation was done under different working condition with different particle size which diameter is from 1mm, 2mm, 3mm, 4mm and 5mm, and different granule concentration which is 1%,2%,3% and 4%.
Simulation results show that wear degree is not uniform in different part of impeller.
[3]Fu-jun Wang: in:Computational fluid dynamics (CFD) software analysis: principles and applications.

To obtain the design criterion ofcurve regression equations and area ratio,Wan Peisun conducted tests on the jet-mixing apparatus and discussed the relationship between its structure parameters[2].He Peijie chose different jet nozzle diameters and different jet nozzle distances and some other parameters to determine the pressure ratio and the flow ratio of jet-mixing apparatus[3].To analyze and compare the mixing performance of different kinds of jet mixing apparatus, Xu Youlin designed 4 forms of jet-mixing apparatus and carried out numerical simulation by using CFD software Fluent flow[4].Meanwhile.Qiu Baijing studied pipe distance, area ratio and inlet angle on the effects of mixing performance of the mixing device by CFD, he obtained some rules between the three structural parameters and the jet mixing properties[5].
At present, the research on jet mixing was limited to the flow field simulation of jet mixing apparatus and experimental analysis, but the jet-mixing device and spray system to integrate a large system for the research didn’t be taken.Therefore, this text studies working state of jet mixing apparatus used in spray system based on the bench test. 1 Working state of jet-mixing apparatus 1.1 The structure and parameters of jet-mixing apparatus A jet-mixing apparatus is mainly composed of jet nozzle, medicine sucking mouth, suction chamber, mixing tube and diffusion tube, its structure is schematically shown in figure1.And the structural parameters of jet-mixing apparatus could be divided into fixed parameters and variable parameters, fixed parameter is a constant parameter in the optimization design and variable parameter refers to changing parameters values in order to explore an optimized parameter in the effects of flow jet to jet-mixing apparatus in simulation design.
The apparatus may appears reflux and cavitation that are thought as failed condition, to avoid back flow and cavitation state, the current research on reflux state of jet-mixing apparatus is less, this paper will study the working state of the jet-mixing apparatus from numerical simulation and experimental study. 2 Bench test 2.1 The bench test device The main parts of the test device are: online mixing test platform, it consists of dynamic liquid pump, water tank, pesticide tank, jet mixer, spraying system and the measuring elements, the structure and the test bench of online automatic mixing test platform are both shown in figure 2.
[4] Xu Youlin,Zhou Fengfang,Guo Jingkun.Flow Field Simulation of Chemical Mixing Process for Direct Injection System based on CFD[C].2008:ASABE International Meeting,Rhode [5] Qiu Baijing,Xu Xichao,Yang Ning.The simulation analysis of the influence of structure paraments on the mixing performance of jet mixing device[J],Transaction of the Chinese Society for Agricultural Machinery,2011, 42(6): 172~174.

In this paper, by the way of numerical simulation, the ground surface temperature field and indoor air temperature field of three different types of floor radiant system are compared using the CFD software FLUENT.
Then the CFD software FLUENT is used to get the numerical calculation result, which can also processed by the software.
Conclusions The temperature in the simulation process in this paper is a little higher.
Piippo, Uneven gridding of thermal nodal networks in floor heating simulations, Energy and Buildings 39 (2007) 1107–1114
Simulation analysis on the impact of coverings on floor heating [J].

So the temperature field was simulated by the application of the CFD software, as shown in Fig.2, Which the actual temperature field was measured by the infrared imaging system.
Table 1 lists the results of simulation and measurement temperature field.
Comparing between simulation and measurement temperature data, it shows that simulation results are in good agreement with experimental data.
CFD method can solve the steady heat transfer.
The results demonstrate effectiveness of the simulation results.

Numerical simulations of mixing enhancement have been studied by Mekkes et al [9], and results of numerical simulations of constant-area combustion by In-Seuck Jeung et al [10,11] are also important in this regard.
A numerical simulation (CFD) approach is applied whereby the total combustor length is constrained by the conditions that 80% or more of the combustion product species are formed, 90% or more of the maximum static pressure rise has occurred and temperature is no more than 2500K.
CFD Approach.
Aerothermodynamic-CFD Design Results Total Combustor Length.
Numerical simulations are carried out for reduction of scramjet combustor length.

A self-priming process was numerically simulated in a diffuser element using a computational fluid dynamics program (CFD-ACE+).
Diffuser Simulation The computational fluid dynamics (CFD) simulations show the passive valve effect of the diffuser elements with a high degree of accuracy [7].
Numerical analysis was performed for a diffuser element in the fabricated valveless micropump using the commercial program (CFD-ACE+).
The simulations were done using water as liquid at 300K and based on the Navier-Stokes equation.
The simulation results predict minimal bubble generations at the hydrophilic surface and rapid flow rate at the hydrophobic surface.

Generally, a steady solution of pressure information can be obtained based on traditional CFD simulation if the inlet velocity of pipe is time independent.
In the field of CFD, it is easy to result in numerical instability given the strong oscillation of fluid velocity.
Similarly, the simulation of amplitude 3.65m/s lasted 8.5s only (Fig. 8-c).
It is found that the residual of simulation with cavitation model is much lower than that of simulation without cavitation model (Fig. 10).
Besides, simulations with and without cavitation model are tested.