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This paper aims to numerically investigate and compare the effectiveness of CFD (Computational Fluid Dynamics) with experimental results.
This paper aims to numerically investigate and compare the effectiveness of CFD (Computational Fluid Dynamics) with experimental results.
In this study, we simultaneously compare the experiments and CFD simulations regrading two different fire loads of 1 and 5MW for 6 minutes and 20 minutes, respectively.
Generally speaking, simulations results are in a good agreement with experimental observations.
The following conclusions can be drawn form simulation results: 1.

Optimization of Sonic Boom Suppression by Off-body Energy Deposition FENG Xiao-qiang1, a, LI Zhan-ke2,b SANG Jian-hua3,c, SONG Bi-feng4,d, 1School of Aeronautics, Northwestern Polytechnical University, Xi’an 710072, China 2School of Aeronautics, Northwestern Polytechnical University, Xi’an 710072, China 3School of Aeronautics, Northwestern Polytechnical University, Xi’an 710072, China 4School of Aeronautics, Northwestern Polytechnical University, Xi’an 710072, China a fxqnwpu@163.com, b lzk@nwpu.edu.cn, c angianua@yeah.net, dbfsong@nwpu.edu.cn Keywords: sonic boom; CFD; off-body energy deposition; shock wave Abstract: Sonic boom suppression method is the key technology of next generation supersonic aircraft.
Off-body energy deposition analysis software is developed based on CFD, waveform parameter method and NSGA-II genetic algorithm.
Wu Li researched the mixed fidelity approach for design of low boom supersonic aircraft by using CFD and SGD inverse design method [3].
Figure 2 Sketch of sonic boom suppression by off-body energy deposition 2.2 Numerical simulation method The effects of energy deposition are investigated using a three dimensional Euler equations and the set of Euler equations with energy deposition in GCC coordinates are shown in Eq.4~Eq.8 [7]: (4) (5) (6) (7) (8) Where ρ and p denote the gas density and pressure, respectively, u1,u2 and u3 are the x, y and z velocity components, e is the total energy of the gas per unit volume,γ is the specific heats, and N is the power density of the source of energy released in (W/m³).
Prediction of sonic boom signature using Euler-full potential CFD with grid adaptation and shock fitting[R].

Analysis and Study of Back Eddy Flow Field Effecting Compact by Angle of Meeting Flow of Reef Kaimin Wang1,a*, Yihong Yang 2,b, Yong Chen3,d, Shuguang Luan1,c 1School of Marine and Civil Engineering, Dalian Ocean University, Dalian 116023, China 2 Shandong Association of Oceanic Engineering, Aquatic Design Institute,Jinan 250013, China; 3Center for Marine Ranching Engineering Science Research of Liaoning, Dalian Ocean University, Dalian 116023, China awkm@dlou.edu.cn, byangyihong-2008@163.com, cchenyonng@dlou.edu.cn , dshugluan@qq.com Key words: Artificial reef; meeting flow angle; back Eddy; Numerical Simulation Abstract: By changing artificial-reef’s meeting flow angle, Use the CFD imitate three-dimensional flow field under the compaction of constant flow, and analyze the effect of back eddy flow field quantitatively.
Now at home and abroad, the research method about artificial reef mainly includes physical model experiment, wind tunnel experiment and numerical simulation.
Use CFD software, carry on numerical simulation tests for six kinds of reef model which differ in meeting flow angle, by change the meeting flow angle, analyze the back eddy flow field effecting, conclude the best meeting flow angle, in order to provide a basis and reference of the reef’s design and make for our country.
Dim the bottom side length as reef length, then, the length of reef model A; B; C; D; E; F are 2m; 2.54m; 3.15m; 4m; 5.46m; 9.46m respectively. 2.5 Tests and determination of boundary conditions The artificial reefs are set in coastal waters generally, in this paper, the computational simulation depth of water was set as 15m, and the flow velocity was set as 2m/s.
Fig.3 Variation about the height; length; width of back eddy with the meeting flow angle Conclusion Paper used CFD software, carried on numerical simulation tests for six kinds of reef model which differ in meeting flow angle, analyzed the back eddy flow field effecting, conclude that: When the meeting flow angle changes from 90° to 15°, the height of the back eddy flow increase at first then decrease, when the angle is 75°, the height of back eddy flow is the largest, when the angle between 90° and 60°, the height achieves larger value.

SIMULATION OF SPOUTED BED USING A EULERIAN MULTIPHASE MODEL C.
The pattern of solid and gas flows in a spouted bed was numerically simulated using a CFD modeling technique.
A commercially available, control-volume-based code FLUENT 6.1 was chosen to carry out the computer simulations.
Numerical simulations have become popular in the field of dense gas-solid two-phase flows.
Many researches have been making numerical simulations of fluidized beds and spouted beds.

This work uses CFD tool in ANSYS CFX software to calculate the aerodynamics parameters generated by main rotor using in UAV.
This work uses ANSYS CFX, a CFD tool to calculate the aerodynamics parameters generated by main rotor using in UAV using the ideal of simulation that were remarked in [3-5].
It can only be calculated after the CFD simulation, since the actual boundary layer profile is needed for this.
In CFD, it is used in turbulence models that need the wall distance for modelling the influence of the Reynolds stress tensor.
Ilinca, “Assessment of turbulence model for flow simulation around a wind turbine airfoil,” Modeling and Simulation in Engineering, February 2011

Computational Fluid Dynamics (CFD)-based Models Under this category, some models directly use viscosity laws in simulation and some others are based on an equivalent dynamic viscosity definition from CSM models, also called solid mechanics based dynamic viscosity [2, 16, 19, 30-51].
Multiphysics (CSM-CFD) Models There are models which use both CFD and CSM approaches to predict strains and residual stresses, along with flow characteristics: First they use a CFD approach based on the equivalent dynamic viscosity definition from CSM to predict temperature distribution and the shear stress near tool-material interface.
Xu, Solid mechanics simulation of friction stir welding process, Trans.
Micari, Meshless simulation of friction stir welding.
Wagoner, Numerical simulation of friction stir butt welding process for AA5083-H18 sheets.

Study on the Effect of Different Rear Windscreen Angles on Aerodynamic Characteristic of the Automobile HaiTao Bao Faculty of Transportation Engineering, Huaiyin Institute of Technology, Huai’an, China bht4931530@163.com Keywords: automobile; rear windscreen angle; aerodynamic characters; CFD .
Numerical simulation of external flow field around automobile has been performed to study the effect of different headstock shape on aerodynamicdrag [1].
In this numerical simulation, the effects of compressibility can be ignored because the Mach number based on the automobile velocity is relatively small.
The turbulence model constants chosen for use in this simulation are listed in table 1.
[5] Liang Jianyong, Liang Jun, Fan Shijie& Zhang Jialin：Comparison Among k-ε Turbulence Models in CFD Analysis on Flow Field Around a Car Automotive Engineering , Vol. 30 (2008) , p. 847 [6] Fluent Inc.

Large Eddy Simulation of the Gas–Liquid Flow in a Cylindrical Cross-Sectioned Bubble Column W.L.
Numerical Results The simulation example is shown schematically in Figure 1.
Large eddy simulation of con>ned swirling flow.
Computational fluid dynamics (CFD) analysis of multiphase chemical reactors.
Dynamic simulation of dispersed gas–liquid two-phase flow using a discrete bubble model.

Simulation and Experiment of Residence Time Distribution in Short-Contact Cyclone Reactors Zhang Yu-chun1,a, Zou Wei 2,b 1School of Agricultral and Food Engineering, Shandong University of Technology, Zibo, Shandong, 255049, China 2Metrological Research Centre, Sinopec Gas Company, Wuhan, Hubei, 430040, China azhangyuchun29@163.com, bzouwei2006@163.com Keywords: short-contact cyclone reactor, component concentration, residence time distribution, tracer method, CFD.
Numerical simulation techniques are one way of modeling for such systems.
Computational fluid dynamics (CFD) tools are becoming powerful and popular to conduct reactor design and diagnosis [4,5].
In one word, the simulated results fit the experimental data well, the error is small, it shows that the simulation method could predict the residence time distribution effectively, the simulated results are reliable and accurate.
Contours of the component concentrations on different planes predicted by simulation.

Afterwards, import the data to CFD processor Gambit software, using spline curve to fit values at each section point so as to establish a smooth three-dimensional propeller surface.
Figure 3 Calculated value and test value Curve fitting comparison From figure 3 we can conclude: The calculation results and experimental results are basically identical, and the average error is about 3%.on the whole, the simulation result is good, Analyze the error causes, there is a deviation between the physical model and digital model, experimental and simulation conditions cannot be exactly same (for example, the Reynolds number and hydraulic wake).
Therefore, using CFD simulate propeller under open water can satisfy the demand of practical engineering application.
Based on the CFD duct propeller hydrodynamic performance research .
Application and research of propeller hydrodynamic performance calculation by means of CFD.