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Fig.3 Air flow model Fig.4 Gas in goaf and workface diffusion model Fig.5 Nephogram of gas concentrations distribution in goaf without drainage measure Analysis of numerical simulation of draining goaf methane with pipe at the upper corner To make sure of the proper methane drainage parameters of the upper corner, coordinated with actual conditions of N3-8 workface, numerical simulation on the height of 0.6-2.4m from the bottom in return airway is adopted.
According to the actual situation of Changcun coal mine working face N3-8 site,the upper corner area is blocked with closed wall piled sacks filled with waste rock.A relatively confined space is formed in the upper corner that gas can gather, thus facilitating the drainage.In the numerical simulation process, closed wall blocked on the corner can be approximately regarded as a long-2m, thick 1m ,high 1.8m entity, the entity for the porous medium, the porosity of 0.5%, the viscous coefficient.The gas in the working face of simulation after the drainage effect as shown in Figure 10.The simulation results show that drainage gas concentration in the pipe can reach 31%, the concentration of gas in upper corner down to 0.6% after the plugging measures are taken at the upper corner.
Field application situation According to the drainage parameters determined by the numerical simulation,we do the mobile gas extraction technology experiments in the face of the Lu'an Group Changcun Coal N3-8.The site gas concentration measured results and numerical simulation results are basically the same.The concrete measured data shown in Fig11 .
(5)The face of the Changcun Coal N3-8 is used as experimental field,doing the piping layout based on the parameters determined by numerical simulation,and the actual application results and the simulation results are basically the same.The drag pipe drainage technology provides a feasible new method to manage the gas of the upper corner.It has important significance for reducing the gas concentration of the upper corner and ensuring safety in production.
[In Chinese] [3] Hu Qianting,Liang Yunpei,Liu Jianzhong.CFD simulation of goaf gas now patterns[J].Journal of China Coal Society,2007,32(7):719-723.

Numerical Simulation on Air Volume Flow Rate Distribution of Stator Ducts for Salient Pole Synchronous Motor Li Liu 1, Yiping Lu 1, a, Jiade Han1, Xuemei Sun1 1School of Mechanical and Power Engineering, Harbin University of Science and Technology, Harbin, Heilongjiang, 150080, China aemail:luyp2010@aliyun.com Keywords: 3D Flow Field; Numerical Simulation; Salient Pole Synchronous Motor; Stator Duct Abstract.
The air volume flow rate distribution of stator ducts along axial and circumferential was analyzed based on CFD.
Simulation results and analysis Accuracy of the analysis results.
Although the basic principles of the two calculation methods were different, the relative error was 0.5%, indicating that the simulation results were accurate.
[5] Yiping Lu, CenYu Liu, MengQi Li and so on. 3D Flow Field Numerical Simulation of Some Doubly Synchronous Motor [J].

In this paper, aerodynamic properties of Blended Wing Body (BWB) civil aircraft are studied by two models: one calls complete model that is computed by numerical simulation coupling equations of motion with the Navier-Stokes equations, and the other doesn’t consider the equations of motion (without dynamic response).
Some groups have studied this phenomenon by CFD methods [10], while most care the effect on airfoil or wings.
Fig. 2 The function of gust Fig.3 CFD grid of the BWB Results and discussion The flight conditions are list in table 2.

CFD modelling [8] has been utilized to study the effect of different runner[9] and gating systems.
With the recent development in computer simulation and advance numerical techniques the thermal modulus has been introduced.
Special thanks to Design and Simulation team at Foundry Service Centre for their assistance in this work, Briter Engineering Pvt.
Shepel, "Numerical simulation of filling and solidification of permanent mold castings," applied Thermal Engineering, pp. 229-248, 2002
Yeh-Liang Hsu, "Computer simulation of casting process of aluminium wheels – a case study," J.

Simulations were performed with a ratio of radius = 0.714. 
Numerical model The numerical simulation was carried out by the Fluent 16.0 code. 
-Simulation results are in good agreement with the experimental data.
Lohse, Direct numerical simulation of Taylor-Couette flow with grooved walls: torque scaling and flow structure, Journal of Fluid Mechanics. 794 (2016) 746-774. http://dx.doi.org/10.1017/jfm.2016.179 [27] Y.
Wilcox, Turbulence Modeling for CFD.

The paper studies the relationship between axial force and breadth of back blade by numerical simulation and experiment.
Table 1 The range of back blades breadth t back blades breadth t （mm） 2 3 4 5 5.5 t/s (%) 33.3 50 66.7 83.3 91.2 Numerical Simulation and Analysis To the centrifugal flow field numerical simulation, the first step is to using the corresponding three-dimensional CAD software to modeling the flow field area, the flow field grid by the discrete space only after modeling of the fluid region, and finally set the boundary conditions of the end CFD software is used to import mesh solver for a reasonable simulation.
And then compare the results of numerical simulation and the experiment in graph is shown in Fig. 8.
Fig. 8 The results of numerical simulation and the test Comparison graph It can be seen from the above graph that the two curves of numerical simulation result and experimental result is basically the same, which proves reliability of the numerical simulate result.
Moreover, it is clearly shown that the value of the numerical simulation result is larger than experiment result.

According to the structural characteristics of tent air-conditioner, the inner flow mechanism and influence factors on aerodynamic characteristics of the air duct was investigated by using Fluent commercial CFD code.
Mathematic model and simulation model setting of the air duct of tent air-conditioner According to air duct structure characteristics of tent air-conditioner, feasible simulation model established is showed in Fig. 2.
（a）Velocity curve of inlet （b）Velocity curve of outlet Fig.5 Velocity curve of inlet and outlet Numerical simulation result shows the air flow rate is 105m3/ h.
Numerical simulation air flow rate: Q=125m3/ h, air flow increase △Q=18.9%.
The simulation results show that the air volume of optimal air duct is 125 m3/ h, increase by18.9% compared to the original duct.

For multi-zone CHEMKIN simulation, we need to define the initial temperature Ti, equivalence fuel/air ratiof, residual mass (RMF) fraction, and mass fraction (MF) of total mass for each zone.
A three-dimensional CFD model was used to study a complete cycle and provided initial conditions (at IVC) for CHEMKIN simulation.
N-heptane was chosed as the representative of diesel in our chemical kinetic simulation.
Effect of the ethanol addition on simulation and the experimental in-cylinder pressure and heat release rate The effect of ethanol on LTHR.
Our simulation results of the pressure and the heat release rate (HRR) are shown in figure 2.

Fu School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, China zhangfh@hit.edu.cn, robertwsf@sina.com, qiangzi0814@163.com, pqfuln@hit.edu.cn Keywords: aerostatic, radial-thrust bearing, loading capacity, stiffness, CFD, finite volume method Abstract The working performance of the spindle system is the most important factor to embody the overall performance of the machine tool.
Simulation results show that this special structure of bearing module can supply enough load capacity and stiffness for the machine tool.
a) Influence of orifice diameter on the loading capacity b) Influence of orifice diameter on the static stiffness c) Influence of orifice diameter on the mass flow of the bearing Fig. 3 Axial loading capacity, stiffness and mass flow rate of the gas bearing with offset values under different orifice diameters a) Influence of the number of orifices on the loading capacity b) Influence of the number of orifices on the static stiffness c) Influence of the number of orifices on the mass flow of the bearing Fig. 4 Axial loading capacity, stiffness and mass flow rate of the gas bearing with offset values under different orifices number Axial stiffness experiment To prove the accuracy of the numerical simulation results, the axial stiffness of the bearing measurement experiment is carried as shown in Fig. 5.
The simulation result is 3507.78 N/μm using the fluent software.
From the numerical simulation results and associated discussion above, the following conclusions can be drawn: a) Compared with thickness direction of the film, the other two directions are too large that meshed grid distortion is often emerged.

The theoretical analysis and numerical simulation for wall heat transferring process of the gas-infrared heated room is finished in this paper.
Simulations on Exterior Wall Heat Transfer Characteristics of Radiant Heating Room The Conditions of Numerical Simulation.
A numerical simulation on a gas heating plant was processed.
Simulation on Exterior Wall Surface Temperature Distribution.
CFD software is adopted to simulate the indoor temperature field, and the indoor temperature distribution of this plant is shown in Fig.3.