An experimental analysis of the flow field in a three-dimensional model of the human carotid artery bifurcation

Extensive experimental studies on axial compressor bleed-flow systems have been carried out on a three dimensional model of a generic bleed-flow configuration typical for aero engines. The compressor flow is modeled as a clean annular flow. One row of stator vanes is used to impart a constant swirl upstream of the bleed system. The rig is designed modularly in order to allow for inexpensive changes in all of its components and therefore to enlarge the variability of the model. The research is focused onto the generation of an experimental data base, which can be used to derive correlations for the calculation of effective areas and pressure losses. Those data are gained using steady pneumatic measurement technique. In addition, the highly complex flow field in the manifold, which has an important effect onto the bleed-flow, is analyzed using Doppler-Global-Velocimetry (DGV). These measurements were conducted in collaboration with DLR Cologne, who have developed the DGV technique. In this paper the flow field in the manifold is analyzed in detail for two different configurations featuring two and four bleed ducts, respectively. Furthermore the use of a flush design of the slot is compared with a lip design. These data are compared to results from the literature achieved using 2-dimensional configurations.

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Cold and Thermal Flow Field Analysis of Gasoline Engine Exhaust Port Based on CFD and RE

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1079-1080.918 ◽

2014 ◽

Vol 1079-1080 ◽

pp. 918-921

Author(s):

Dan Han ◽

Zhi Xia He ◽

Guo Jun Zhang ◽

Shuo Wang ◽

Qian Wang

Keyword(s):

Flow Field ◽

Laser Scanning ◽

Gasoline Engine ◽

Three Dimensional ◽

Field Analysis ◽

Dimensional Model ◽

Three Dimensional Model ◽

Engine Exhaust ◽

Exhaust Port ◽

Cold State

Exhaust passage is a significant part of the gasoline engine, its structure will affects the gas flow characteristics of the engine directly [1]. So, research and analysis of the exhaust tract is essential. In this paper, a detailed analysis of the flow field under cold state and hot state was made. For a start, the method of laser scanning and UG software were used to reverse modeling engine exhaust port and get the three-dimensional model. The next, the unstructured grid with local mesh refinement scheme was used to mesh this three-dimensional model with ICEM. After this, numerical simulations of the exhaust passage with five different valve lifts were carried out under thermal and cold conditions. Finally, comparing the velocity field and pressure field of the exhaust passage under cold state and thermal state, it can be find that the flow field under hot and cold state have similar characteristics. The results of this paper can provide a theoretical basis for following researches of the engine exhaust port.

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Three Dimensional Model of a High Temperature PEMFC. Study of the Flow Field Effect on Performance

Fuel Cells ◽

10.1002/fuce.201100197 ◽

2012 ◽

Vol 12 (4) ◽

pp. 566-576 ◽

Cited By ~ 22

Author(s):

T. Sousa ◽

M. Mamlouk ◽

K. Scott ◽

C. M. Rangel

Keyword(s):

High Temperature ◽

Flow Field ◽

Field Effect ◽

Three Dimensional ◽

Dimensional Model ◽

Three Dimensional Model

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Simulation Research of Small Holes by Combined Ultrasonic and Electrochemical Machining Based on CFX

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.584.60 ◽

2013 ◽

Vol 584 ◽

pp. 60-66 ◽

Cited By ~ 1

Author(s):

Ze Xiang Liu ◽

Min Kang ◽

Xiu Qing Fu

Keyword(s):

Flow Field ◽

Three Dimensional ◽

Electrochemical Machining ◽

Dimensional Model ◽

Three Dimensional Model ◽

Two Phase ◽

Simulation Research ◽

Ansys Cfx ◽

Phase Fluid ◽

Small Holes

A device was designed to study the small holes by the rotary combined ultrasonic and electrochemical machining, and the gap between cathode and anode in the processing was also analyzed. A three-dimensional model of flow field was developed in ANSYS CFX software based on FEM by the gas-liquid two-phase fluid cavitations model as well as the effect of rotary cathode and the vibrated cathode to the flow field was analyzed. The simulation showed that the pressure and the velocity of the electrolyte in the gap were oscillated by additional motion of cathode, which is helpful to the electrochemical machining. The comparison of rotary electrochemical machining and the rotary combined ultrasonic and electrochemical machining showed that the rotary combined ultrasonic and electrochemical machining has better ability of making small holes than that of rotary electrochemical machining

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Hydrodynamics Simulation of Gas-Solid Flow Field in Conveying Vessel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.1528 ◽

2011 ◽

Vol 236-238 ◽

pp. 1528-1531

Author(s):

Yue Cui ◽

Hong Gao ◽

Jin Sheng Sun ◽

Xu Chen

Keyword(s):

Flow Field ◽

Uniform Distribution ◽

Volume Fraction ◽

Dead Zone ◽

Solid Volume Fraction ◽

Three Dimensional ◽

Gas Velocity ◽

Dimensional Model ◽

Three Dimensional Model ◽

Solid Flow

Flow field of gas and particles in a conveying vessel is investigated by use of a three-dimensional model combined Eulerian approach. Because of the nozzles’ arrangement in this study, the flow patterns of spouts and bubbles can be seen in the gas-solid flow field, which lead to a non-uniform distribution of gas velocity. Solid volume fraction is high near the bottom and low at the top part. The porosity rises with gas speed increasing, as well as time. An improvement is examined to remove the dead zone at the bottom, which results in particles remaining.

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Simulation of the Flow Parameters of the Multi-Microchannel Aerostatic Restrictor

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.241-244.1278 ◽

2012 ◽

Vol 241-244 ◽

pp. 1278-1284

Author(s):

Yu Bing Zhang ◽

Cai Qin Li ◽

Dong Sheng Li

Keyword(s):

Numerical Simulation ◽

Flow Field ◽

Film Thickness ◽

Three Dimensional ◽

Simulation Method ◽

Gas Pressure ◽

Dimensional Model ◽

Three Dimensional Model ◽

Flow Parameters ◽

Numerical Simulation Method

A numerical simulation method, FLUENT,has been selected to simulate the flow field parameters of the multi-microchannel aerostatic restrictor. Pressure, temperature and velocity distributions of the restrictor under different gas film thickness and gas pressure were got and compared. Used Pro / E to establish three-dimensional model of restrictor and imported it into GAMBIT for meshing, and then used FLUENT for simulation.

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