Search results

Blast simulation CFD was a traditional tool in the aerospace industry focusing on the problems of supersonic and hypersonic flight, but it has the same basic equations of motion and is applicable to simulate blast modelling problems.
However, only recently, with the enhancement of CFD techniques, of numerical methods and faster solver algorithms; and the tremendous development of computer technology, CFD was applied into blast simulation to investigate the problems of blast wave propagation and its interaction with structures [7].
CFD modelling was performed in code Air3D which was designed particularly for blast wave simulation and has been validated against a number of experiments.
The simulation of blast load of 1kg, 2kg, 3kg and 10 kg were performed to get a range of blast profiles.
After simulation the pressure time history has been recorded for each and every Explosive.

Performance Improvement on Axial-Flow Fan by imposing Proper Frame Ribs Sheam-Chyun Lin1,a, Fu-Yin Wang1,b, Cheng-Ju Chang1,c, Hung-Cheng Yen2,d, and Yung-Jen Cheng2,e 1National Taiwan University of Science and Technology, Taipei, Taiwan 2Industrial Technology Research Institute, Hsinchu, Taiwan asclynn@mail.ntust.edu.tw, bD9703302@mail.ntust.edu.tw, cD9603301@mail.ntust.edu.tw dBrianyen@itri.org.tw, eeric_cheng@itri.org.tw Keywords: Axial-Flow Fan, Frame Rib, CFD simulation, Hydraulic Efficiency, System Resistance.
Therefore, this study intends to investigate the geometrical parameters of the frame rib systematically by using an integrated scheme, which consists of numerical simulation, mockup fabrication, and experimental verification.
Design Alternatives and CFD Results It is important to obtain the fan impeller generating low noise and high performance.
Star-CD is a commercial CFD code, which solves the Navier-Stokes equation using an unstructured finite-volume-method [7].
The result indicates that experimental performance agrees to that of numerical simulations on both maximum volumetric flow rate and static pressure.

Apply the CFD numerical simulation the internal flow field and noise when the control valve is bonnet leakage and trouble-free.
This article through the establishment of control valve bonnet leakage and trouble-free flow model, the application of CFD numerical simulation and analysis of the internal flow field and the distribution of the noise, it provides theoretical basis for further research of valve bonnet leakage.
Fig. 1 Bonnet outside leakage schematic Meshing and Simulation Settings The flow channel model need meshing before CFD simulation.
Conclusion Establishing the valve trouble-free and bonnet leakage flow model, and applying the CFD numerical simulation of internal flow field and noise, obtained the following conclusions
Numerical Simulation and Analysis of Interior Flow Field in Control Valves under the Blocking Fault [J].

Analysis on Tow-phase Flow of WJ-4FB Explosion-proof Scraper Waste Gas Treatment Tank Based on CFD Wei Zhang, Wenming Zhang, Miaomiao Guo School of Mechanical Engineering, University of Science and Technology Beijing, China ustb_dzw@126.com Keywords: Waste Gas Treatment Tank; Gas-liquid Two-phase Flow Analysis; CFD Abstract.
And establish the gas-liquid two-phase flow simplified model based on CFD.
Through the numerical simulation of the gas-liquid two-phase flow transient flow pattern, draw two-phase flow figures and gas content distribution curve .Further analysis of the gas-liquid two-phase flow, this paper obtains initial gas velocity, static level, internal mounting member and other influencing factors.
As shown in fig. 7 five speed air content have an intersection point, approximately between 0.55-0.57 range, y = 320 mm in the simulation system, this is the gas-liquid mixed flow under a state of equilibrium liquid level position.
[7] Ngy Srun AP.A Simple Engine Cooling System Simulation Model[C].SAE 1999-01-0237.

Numerical simulation method for aero-acoustics based on acoustics analogy shows some promise to CAA.
As a result of [13], the FW-H solver can now be integrated in the CFD solver and works in a parallel computing environment to provide a far field acoustic pressure prediction in line with the CFD near field prediction.
According to reference[17], the time-step (Dt) of 2×10-6 s was used for the transient simulation.
D., Simulation of supersonic cavity flow using 3D RANS equations, AIAA paper 2004-4966
Koutsavdis, A versatile implementation of acoustic analogy based noise prediction method in a general-purpose CFD, AIAA paper, 2003-3202.

Two-phase Flow CFD Simulations of Bubble Crystallization Tube Pengfei Zhang1,a, Jianlong Hou1,b and Kexue Fang1,c 1School of Chemical Engineering, Tianjin University, Tianjin, 300072, China azhangpf@tju.edu.cn, bhoujl2009@163.com, cfangkexue2009@163.com Keywords: CFD, Gas-liquid two phase flow, Bubble crystallization, VOF model Abstract.
Simulations agree well with experimental data.
Simulation region is shown in Fig.1.
At the beginning of the simulation process, in order to reduce simulation time, aeration-tube is filled with gas.
The verification of simulations.

So default value is chosen for the parameter selection of the simulation process.
Analysis of calculation results by CFD The integral pressure contour results of the double nozzle flapper valve by CFD simulation is shown in Fig.5.
The simulation results can be seen that the highest velocity of the fixed orifice is about 150m/s.
Conclusion Application of CFD software with the orthogonal test to the simulation of the internal flow field of the double flapper-nozzle servo valve, the variation of the velocity and pressure flow field can be seen.
Based on Fluent double flapper-nozzle servo valve flow field visualization simulation, J.

However, there exist three major challenges for it: Computing Time: Given a single typical model with one-foot length in each of the three dimensions, it takes several days to have FEA and/or CFD simulation done on a desktop with a 1.5 GHz CPU.
DISPATCH MODULE Simulation Workflow MESH MODULE CFD MODULE FEA MODULE Simulation Workflow MESH MODULE CFD MODULE FEA MODULE Simulation Workflow MESH MODULE CFD MODULE FEA MODULE ...
CFD module.
CFD module receives mesh from Mesh module.
For each CFD simulation, the input files and output files are saved in a specific directory with multiply sub-folders with pre-defined structure.

The investigations of this study were undertaken though a set of experiment and the computational fluid dynamics (CFD) simulation; particularly the latter approach can draw a clear perspective on the flow behavior than observing from the experiment alone.
In addition to the CFD simulation, the static and dynamic pressures including flow direction were read for each test.
The experiment and CFD simulation were designed with regard to the full-factorial scheme, such that the total number of tests was 12 conditions.
The color and vector shown in the CFD simulation results represents the dynamic pressure and flow direction, respectively.
(a) (b) (c)(d) Fig. 4 Experiments and CFD simulations on dynamic pressure for the impact angle of 90 degrees and obstacle thickness of: (a,c) 1 mm and (b,d) 3 mm (a) (b) (c)(d) Fig. 5 Experiments and CFD simulations on dynamic pressure for the impact angle of 22.5 degrees and obstacle thicknesses of: (a,c) 1 mm and (b,d) 3 mm Conclusions The water jet impingement either in normal or oblique fashion can be seen in cleaning and cooling processes.

On the other hand wind flow around the bridge site as well as the environment around the mountain wind flow, wind speed field and the distribution of turbulent flow, etc is obtained by using CFD technology.
At the same time the finite element model is set up to simulate wind environment of real bridge by using CFD technology[2,3], a finite element model of numerical simulation of wind environment of a real bridge and supply the wind effective supplement for environmental monitoring data.
The numerical simulation using Fluent 6.2 software, this numerical simulation considered two cases: there is a real bridge and there is no real bridge.
(2) Wind field of terrain liking bell where the river flows from canyon to the open field have been simulated by CFD.
The results from the numerical simulation results compared with the wind observations showed that numerical simulation of wind field characteristics is consistent with measured properties of wind field.