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The main purpose of the simulation is to assess the stability of the in situ combustion with respect to the unsteadiness induced by the rotor-stator interaction.
Apart from previous attempts, the salient feature of this CFD approach is the new fuel injection concept that consisting of a perforated pipe placed at mid-pitch in the stator row passage.
Fig. 2 Computational domain The simulation was performed within ANSYS CFX environment.
As a first step in the numerical simulation of the in situ reheat, a simple chemistry mechanism has been considered.
Badescu, Numerical Simulation of Turbine 'in-situ' combustion based on multi-step reaction mechanism, SET2006 5th Intl.

In this paper, 3D finite element numerical simulation was performed to investigate the flow in one of the vane units with POLYFLOW.
The results show that numerical simulation is an efficient method to optimize process parameters and the structure of vane extruder.
In this paper, 3D finite element numerical simulation was performed to the flow in one of the vane units with POLYFLOW.
The CFD preporcessor GAMBIT was used to generate the finite element model of vane unit.
Energy Consumption Characteristics of Simulation and Study on Uniaxial Vane Extruder [D].

Aerodynamic characteristics of the wing NACA5312 in ground effect are investigated with the numerical simulation method.
The N-S equations and the k-ε turbulence model are solved by the finite volume method in CFD software.
Model and Grid The shape of three-dimensional WIG is generally complex, and the simulation of ground effect also needs to consider the interaction between ground and aircraft, so the numerical simulation of the computational grid is very complex and the number is very large[5].
Numerical simulation of enhancing aerodynamic characteristics of WIG by modified airfoils.
Numerical Simulation on 3D Multi-element Wings in Ground Effect.

Introduction With the development of the industry, the control cabinet is gradually realized intellectualization.In case of outdoor without shelter,summer temperature,cabinet temperature reaches 40 ˚C, coupled with the solar radiation and the heating element,will make internal temperature of cabinet may exceed the permitted (-10˚C -55˚C )[1].Device running under the high temperature overload for a long time,can cause the performance of electrical components to degraded,even exploded,that affect normal operation of the system,so it is necessary to ensure that temperature is not too high in the cabinet[2].The outdoor double intelligent cabinet temperature calculation is hard, in recent years ,the use of CFD method of numerical simulation study on its document is also increasing,usually a complete numerical simulation process generally include the preprocessor,numerical calculation and post processing.Preprocess is generally divided into geometric modeling,mesh generation.
Once some data change, all need to model (reconstruction or modify) and a series of process,they increased the difficulty of the engineering personnel.In order to make up for deficiencies of the preprocessing of numerical simulation,numerical calculation and post processing.Using the VB language to encapsulate Gambit and Fluent,based on Visual Basic for the redevelopment of intelligent cabinet before the numerical simulation software,the system requirements for the professional design staff is not high,and the operation is simple and quick and improve the work efficiency.
Redevelopment software only need to develop intuitive parameter input interface and function of automatic generation command text files,The author only need to input the parameter of analysis objects in the visual interface, invoke the background Fluent to numerical simulation.[5,6]finally, the simulation results directly back to the user.
Contrast the results of simulation By optimizing exhaust air of the fan, respectively 12m3/min and15 m3/min,the maximum temperature reduced3 ˚C.Choose certain points of the cabinet,carry on the comparison and analysis is shown in Figure 8.
Figure 8.Contrast analysis diagram Conclusion Using VB programming language to redevelopment software of outdoor double intelligent cabinet,the interface is intuitive,easy operation[6] .Processor (geometry modeling and grid division) and post treatment (numerical simulation) and all of the whole process were realized. 1) The module has very good auxiliary function to the numerical simulation of outdoor double intelligent Cabinet,For engineering and technical personnel only need to have a certain understand to structure and working conditions of outdoor double intelligent cabinet,it is enough for outdoor double intelligent cabinet optimized application module. 2) The results of numerical simulation show that the module can be well applied to engineering[8] .

The work presented here, deals with numerical simulations performed in a tube-in-tube heat exchanger to study and compare flow characteristics and thermal performance of a tube-in-tube heat exchanger using water and Al2O3/water nanofluid.
In the present investigation, numerical simulations have been performed in a tube-in-tube heat exchanger by a local element-by-element analysis utilizing e-NTU method, to study and compare flow characteristics and thermal performance of a tube-in-tube heat exchanger using water and Al2O3/water nanofluid.
Fig. 2 Variation of heat transfer rate Fig. 3 Variation of hot fluid temperature Fig. 4 Variation of cooling water temperature Fig. 5 Variation of pressure drop The heat exchanger was also tested using computational fluid dynamics (CFD) software FLUENT.
A model was created (Fig. 6) and temperature contour (Fig. 7) was arrived for the same operating conditions used in the numerical simulation.
CFD results were in good agreement with those of numerical simulation.

Computer simulation has been employed to understand the thermal-flow and combustion phenomena in the burner element to solve operation problems and in search for optimal solutions.
A CFD analysis provides fluid velocity, pressure, temperature, and species concentrations throughout the solution domain.
CFD can also provide detailed parametric studies that can significantly reduce the amount of experimentation necessary to identify problems and to optimize the operating conditions.
Therefore, it is possible to increase the accuracy of the simulations with a minimum number of additional grid points.
The final unstructured grid having 60,432 nodes and 256,084 elements was used in the simulation.

Computational Fluid Dynamics (3-D CFD) analysis has been attempted in [9,10] and demonstrated the advantages of these MR fluid bearings. 2 Steady State Characteristics A commonly used bearing in machinery, the hydrodynamic journal bearing is shown in Fig. 1.
Papadopoulos, CFD analysis of journal bearing hydrodynamic lubrication by Bingham lubricant, Tribology International, 41(2008) 1190-1204
Nikolakopoulos, CFD Simulation of magnetorheological fluid journal bearings, Simulation Modelling and Practice theory, 19 (2011) 1035-1060

Convergence criteria for different parameters is set at 0.00001. 2.5 CFD Solver Settings Pressure based CFD solver [16] is used because of the continuous flow being incompressible in nature.
The simulation was run for 1s of total time with the injection of particles done just for 0.2s which physically represents the actuation time of spray from pressurized inhaler [6].
These results are used for validation of the CFD model used in the present study.
Antunes, pMDI sprays: Theory, experiment and numerical simulation,” Adv.
Tu, CFD modeling of spray atomization for a nasal spray device, Aerosol Sci.

Therefore, many researchers have used computational fluid dynamics (CFD) software to solve problems which can not be solved theoretically and experimentally.
The simulation for the flow velocity field inside and outside the abrasive water jet nozzle has been carried out [2,3].
The simulation model is divided with the hexahedron cell, one of the model is shown in Fig.1.
The k-ξ turbulence model, and the item realizable and non-equilibrium wall functions were used in simulation.
Simulation Result and Analysis The simulation result of Fig. 2 is the velocity field of the three phase flow in the X-Z plane.

Numerical simulation and laboratory experiments was used to research the distribution law of tunnel fire at home and abroad due to the complexity of tunnel fire mechanism.
In English, Cox used CFD to analyze the tunnel fire problem early, ventilation, slope and unstable fire were simulated through establishing the mathematical model of JASM, which simulation results were consistent with experimental results of Zwenberg model [3]; In Japan, M.Dobashi and T.Imai studied vertical and horizontal emergency ventilation systems in the event of a tunnel fire through numerical simulation, and it applied to the tunnel of Higashiyama, in addition, the smoke density varying with time and space was also analyzed [4]; In France, B.Brousse and C.Moret attempted to investigate the smoke spread of different tunnel fire through a three dimensional transient simulation, and it considered the tunnel wall roughness, partial loss of inward and outward and the train piston effect [5]; In America, S.S.Levy and J.
Sandzimier pointed out the relations between the exhaust air rate and smoke control effect, and CFD program combined with Ted Williams tunnel was used to the model of fire [6]; In China, the research on numerical simulation of the tunnel fire started late, Lian Feng employed the method of three dimensional numeric simulation to analyze the fire in certain tunnel and the velocity field and temperature field.
RABT curve and HC curve can better simulate the variation of temperature in the tunnel according to full-scale simulation experiment results of UPTUN.
Mizuno, Numerical simulation of the emergency tunnel ventilation for a tunnel with longitudinal and transverse systems combined, 10th International Symposium on the Aerodynamics & Ventilation of Vehicle Tunnels (2000) [5] B Brousse and C Moret, ID-computer simulations and field fire testing using a chimney limited longitudinal smoke control system, 10th AVVT (2000) [6] S.S.Levy and J.R.Sandzimier, Smoke contral for the Ted Williams Tunnel-a comparative of extraction rate, 10th International Symposium on the Aerodynamics & Ventilation of Vehicle Tunnels (2000) [7] Lian Feng, Wandi Wang, Qixin Yang and Mingnian Wang, J.