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In numerical simulations such unsteady flows require a special treatment.
Distinguishing between numerical dissipation and turbulence decay is another problematic topic in CFD.
As an example, a comparison of the vorticity as obtained in the experiment and from CFD calculations, as performed by the Department of Transport Aircraft, is shown in Fig. 4.
This highlights the need for proper validation of CFD codes.
The two dimensional PSP images have been mapped to the three dimensional CFD grid of the model.

The research will get a more effective ventilation model by comparing the simulation results.
It is further to verify that the simulation method is feasible, and the conclusions obtained on this basis are acceptable. 1.
According to the specific characteristics of the anatomy laboratory, I will simulate five ventilation modes with CFD technology, and then get a better ventilation mode by comparing the simulation results and the test results and provide certain reference significance for improving the air quality of the anatomy laboratory. 2.
Model V will be recalculated, and the comparison of simulation results and the measured results are shown in figure 9~10.
Figure 9 The comparison of simulation results and measured results of wind speed Figure 10 The comparison of simulation results and measured results of formaldehyde concentration 5.

The authors use the method of CFD to simulate the thermal environment of indoor office units, and do optimal design of the DSF breathing system of the building.
A unit of the curtain wall and its construction Methods Computational Fluid Dynamics (CFD) Simulation methods are used in this article to study the thermal environment of the building under different curtain wall construction.
The simulation results of indoor thermal environment with the curtain wall been shaded or not (shown in Fig.2b and Fig.3b) are compared.
We can draw the relationship of active ventilation speed and indoor average temperature based on several simulations (Fig.4.).
Residential building naturally ventilated room thermal environment simulation analysis.

In order to study the dynamic changes of the internal flow field physical quantities in the hydraulic buffer of a special equipment, based on the Computational Fluid Dynamics (CFD), a three-dimensional incompressible and viscous model under unsteady condition is created.
Comparing the pressure of working chamber I from simulations with experimental data (as shown in Fig 9), it can be found that: in the Early period of the simulation (0~10ms) and the Later period of the simulation (40~60ms), simulation result is essentially the same as experimental data, but simulation result is slightly larger than experimental data as a whole.
Fig.8 Distribution of lowest negative pressure points Fig.9 Comparison of simulation result of the pressure of working chamber I with experimental data Conclusions In the simulation process in this paper, hydraulic buffer internal cavity is filled with buffer solution, compressible gas was replaced by incompressible liquid, so that the calculated pressure values by simulation were higher than the experimental data as a whole.
[2] Zheng Jianguo: Numerical Simulation of Flow Field in a Gun Recoil Mechanism.
[5] Wang Fujun, in: Computational Fluid Dynamics Analysis--Principle and Application of CFD software, Tsinghua University Press, Beijing of China(2004).

In this paper, CFD simulation technology is used to analyze the characteristics of pressure drop in the empty bed.
The simulation results are compared as Fig. 3.
By contrast, porous media model can replace distributor model in fluidized bed simulation. 6 Summary Simulations are carried out to compare pressure drop feature with distributor and porous media model.
The relative error is only 1.16% in the simulation of this paper.
[3] Depypere F, Jan G Pieters and Koen Dewettinck: CFD analysis of air distribution in fluidised bed equipment [J].

Goaf gas flow patterns are simulated by applying the CFD model development method based on FLUENT program.
The result of numerical simulation is consistent with the experiment on the spot and it suggests that studying goaf gas flow patterns by applying CFD model is one of the feasible methods (Hu et al.)[10].The differential equation is solved by using SIMPLE method and the result of gas concentration distribution is gotten while coal mining machine in working face is cutting coal (Liang et al.)[11].Through numerical simulation, the distribution and the law of its variation of gas concentration field in the upper corner under different conditions of pulsed ventilation are obtained and the result of numerical simulation is consistent with the experiment on the spot (Wang et al.)[12].
CFD simulation of goaf gas flow patterns.
Numeric simulation on gas movement law in working face.
Numerical simulation and experimental study of gas transport in the upper corner of mining face under pulsed ventilation.

These models can be classified into three groups: simple empirical formula models, population balance models and computational fluid dynamics (CFD) models [1, 2, 3, 4].
An Euler-Lagrange approach in CFD has been used by XIA to simulate the flow patterns, particle behaviors, and separation mechanisms in TBS. because of the complexity of these models, Galvin’s model and Das’s model are of most interest, they only are discussed here.
But in order to assess the suitability of models, the deviation between the simulation and the tests results is shown in table2.
Table 2 Average deviation between simulation results and tests results[m/s] Models Galvin’s model Das’s model Alien’s law Average Deviation 0.019043 0.024451 0.031507 As shown in table2, the average deviation of Galvin’s model is the lowest, i.e. the values predicted by equations of Galvin’s model are most closes to the experimental data.
K.: CFD simulation of fine particle gravity separation in hindered-settling bed separators.

Study on Force Sensor Based on Gas Pellicle Loading and Pressure Differentials Enlargement Xuguang Sun1,a,Changhai Wang2,b,Kai Qiao3,c Chenglong Feng4,d and Zhen Zhao5,e 1Huaihai Institute of Technology, Lianyungang, Jiangsu, 222000, China 2China University of Mining and Technology, Xuzhou, Jiangsu, 221116, China 3China University of Mining and Technology, Xuzhou, Jiangsu, 221116, China 4China University of Mining and Technology, Xuzhou, Jiangsu, 221116, China 5China University of Mining and Technology, Xuzhou, Jiangsu, 221116, China aXG_sun@sohu.com, b553617377@163.com, cqiaokaicumt@gmail.com d332177685@qq.com, e416310795@qq.com Keywords: the gas pellicle loading, pressure differentials enlargement, pneumatic sensor, the analysis of flow field Abstract: In this paper, a new force and force location sensor based on the principle of gas pellicle loading and pressure differentials enlargement is designed, and the structure, the principle and the analysis of flow field studied by simulation
Analyses of Gas Blanket Pressure Field Simulation For the sensor, in order to study the interior gas flow field condition and the gas film pressure field change situation, CFD simulation software[3] is presently used in the gas film between the interior panel 7 and the exterior panel 6.
Firstly, using CFD for the simulation model design, it includes four vents uniformly distributed 2×2, and the gas film with 42mm long and wide, 0.03mm thickness.
And after establishing the same boundary condition, the simulation computation result provided as follow in the Figure 9 and Figure 10.
Conclusions This paper discusses the manipulator soft capture and proposes a new sensor based on the principle of gas pellicle loading and pressure differentials enlargement. 1).This sensor is mainly implemented by the technology of gas blanket load bearing and pneumatic micrometer system with amplifying function, and can be used to detect the force location, also realize precise non-damage capture for fragile or soft object. 2.The CFD simulation result about the sensor`s gas film shows the flow field pressure distribution: Besides inlet with higher and variational pressure, other places have lower pressure and basically reach to a state of steady; When load is applied, the pressure near the inlet varies in a wide range, and the pressure far from the outlet has less change.

The effect of boundary conditions on simulation of horizontally homogeneous atmospheric boundary layer X.L.
In the simulations of horizontally homogeneous ABL, some useful guidelines for appropriate boundary conditions have been provided.
The governing equations are solved using commercially available CFD code, Fluent, with the segregated method.
As explained by Richards and Norris [1], the spike occurring near the ground results from the numerical discrete scheme used in CFD code.
Schlunzen et al: Best practice guideline for the CFD simulation of flows in the urban environment.

Numerical simulation is carried out by the fluid dynamic analysis software to truly reflect the coupling effect of different types of flow field on various rods of truss structure.
Wind load analysis of typical truss structure based on CFD Structure analysis conditions Based on a certain 1000 tons crawler crane truss structure, establishing truss structures geometric model (see Fig.1).
The comparion between the simulation results and the analysis results according to standard rules is shown in Fig.5.
Conclusions Based on a certain 1000 tons crawler crane truss structure, numerical simulation has been carried out to analyze the effect of wind load on the truss structure in steady-state wind field and dynamic-state wind field.
To the calculation according to the design rules, the analysis based on CFD can accurately simulate the working condition of truss structure, and the information of stress distribution in flow field is expressed comprehensively.