Investigation of Swirler/Dilution Jet Flow Split on Primary Zone Flow Patterns in a Water Model Can-Type Combustor

LDA measurements of the three mean velocity components and the corresponding turbulence intensities have been made to provide qualitative and quantitative information on the flow field in a water model of a can-type gas turbine combustion chamber. The combustor geometry comprised a swirl-driven primary zone, annulus-fed rows of primary and secondary jets, and an exit contraction. The effect of variation of the flow split between the swirler and the dilution holes on the flow pattern in the primary zone has been investigated in detail. Flow visualization studies revealed that significant changes occur in this region due to the interaction between the swirling flow and the radially directed primary jets. A large toroidal recirculation was formed and high levels of turbulence energy were generated in the core of the combustor at low levels of swirler flow rate. As the swirl level increases, the strength of this recirculation was observed to weaken. Beyond a critical level, the primary recirculation was pushed off center and the undesirable feature of a forward velocity on the combustor axis in the primary zone was observed. Despite the dramatic changes brought about in the primary zone, the flow pattern downstream of the secondary jets was practically the same for all flow splits due to the strong mixing caused by the two rows of jets.

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Investigation of Swirler/Dilution Jet Flow Split on Primary Zone Flow Patterns in a Water Model Can-Type Combustor

Volume 2: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/85-gt-180 ◽

1985 ◽

Cited By ~ 2

Author(s):

P. Koutmos ◽

J. J. McGuirk

Keyword(s):

Flow Pattern ◽

Swirling Flow ◽

Quantitative Information ◽

Water Model ◽

Strong Mixing ◽

Turbulence Energy ◽

Flow Visualisation ◽

Mean Velocity ◽

Primary Zone ◽

Primary Jets

LDA measurements of the three mean velocity components and the corresponding turbulence intensities have been made to provide qualitative and quantitative information on the flow field in a water model of a can type gas turbine combustion chamber. The combustor geometry comprised a swirl driven primary zone, annulus fed rows of primary and secondary jets and an exit contraction. The effect of variation of the flow split between the swirler and the dilution holes on the flow pattern in the primary zone has been investigated in detail. Flow visualisation studies revealed that significant changes occur in this region due to the interaction between the swirling flow and the radially directed primary jets. A large toroidal recirculation was formed and high levels of turbulence energy generated in the core of the combustor at low levels of swirler flow rate. As the swirl level increases the strength of this recirculation was observed to weaken and become less stable. Beyond a critical level, the primary recirculation was pushed off centre and the undesirable feature of a forward velocity on the combustor axis in the primary zone was observed. Despite the dramatic changes brought about in the primary zone the flow pattern downstream of the secondary jets was practically the same for all flow splits due to the strong mixing caused by the two rows of jets.

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Flow pattern velocity and turbulence energy measurements and predictions in a water model of an argon-stirred ladle

Metallurgical Transactions B ◽

10.1007/bf02654928 ◽

1976 ◽

Vol 7 (2) ◽

pp. 287-295 ◽

Cited By ~ 67

Author(s):

J. Szekely ◽

H. J. Wang ◽

K. M. Kiser

Keyword(s):

Flow Pattern ◽

Water Model ◽

Turbulence Energy

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The Model Analysis of Inclusion Moving in the Swirl Flow Zone Sourcing from the Inner-Swirl-Type Turbulence Controller in Tundish

High Temperature Materials and Processes ◽

10.1515/htmp-2016-0135 ◽

2017 ◽

Vol 36 (5) ◽

pp. 541-550 ◽

Cited By ~ 4

Author(s):

Yan Jin ◽

Chen Ye ◽

Xiao Luo ◽

Hui Yuan ◽

Changgui Cheng

Keyword(s):

Flow Field ◽

Swirling Flow ◽

Mathematic Model ◽

Swirl Flow ◽

Water Model ◽

Medium Size ◽

Force Analysis ◽

Inclusion Removal ◽

Flow Band ◽

Turbulence Inhibitor

AbstractIn order to improve the inclusion removal property of the tundish, the mathematic model for simulation of the flow field sourced from inner-swirl-type turbulence controller (ISTTC) was developed, in which there were six blades arranged with an eccentric angle (θ) counterclockwise. Based on the mathematical and water model, the effect of inclusion removal in the swirling flow field formed by ISTTC was analyzed. It was found that ISTTC had got the better effect of inhibiting turbulence in tundish than traditional turbulence inhibitor (TI). As the blades eccentric angle (θ) of ISTTC increasing, the intensity of swirling flow above it increased. The maximum rotate speed of fluid in swirling flow band driven by ISTTC (θ=45°) was equal to 25 rmp. Based on the force analysis of inclusion in swirling flow sourced from ISTTC, the removal effect of medium size inclusion by ISTTC was attributed to the centripetal force (Fct) of swirling flow, but removal effect of ISTTC to small size inclusion was more depend on its better turbulence depression behavior.

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Comparison of a Nonlinear k-ε Turbulence Closure Model With Stress Transport Models

13th Computers in Engineering Conference ◽

10.1115/cie1993-0086 ◽

1993 ◽

Author(s):

Muhammad A. R. Sharif ◽

Yat-Kit E. Wong

Keyword(s):

Pipe Flow ◽

Flow Problem ◽

Swirling Flow ◽

Transport Model ◽

Turbulent Pipe Flow ◽

Turbulence Closure ◽

Closure Model ◽

Transport Models ◽

Mean Velocity ◽

Turbulence Closure Model

Abstract The performance of a nonlinear k-ϵ turbulence closure model (NKEM), in the prediction of isothermal incompressible turbulent flows, is compared with that of the stress transport models such as the differential Reynolds stress transport model (RSTM) and the algebraic stress transport model (ASTM). Fully developed turbulent pipe flow and confined turbulent swirling flow with a central non-swirling jet are numerically predicted using the Marker and Cell (MAC) finite difference method. Comparison of the prediction with the experiment show that all three models perform reasonably well for the pipe flow problem. For the swirling flow problem, the RSTM and ASTM is superior than the NKEM. RSTM and ASTM provide good agreement with measured mean velocity profiles. However, the turbulent stresses are over- or under-predicted. NKEM performs badly in prediction of mean velocity as well as the turbulent stresses.

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Effective Desiliconization Method with Strong Mixing of Agent in Swirling Flow of Hot Metal

ISIJ International ◽

10.2355/isijinternational.54.1813 ◽

2014 ◽

Vol 54 (8) ◽

pp. 1813-1822 ◽

Cited By ~ 4

Author(s):

Yu-ichi Uchida ◽

Seiji Nabeshima ◽

Yasuo Kishimoto ◽

Yuji Miki

Keyword(s):

Swirling Flow ◽

Strong Mixing ◽

Hot Metal

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Effect of Slag Layer on Flow Patterns in a Gas Stirred Ladle

Materials Science Forum ◽

10.4028/www.scientific.net/msf.510-511.490 ◽

2006 ◽

Vol 510-511 ◽

pp. 490-493 ◽

Cited By ~ 4

Author(s):

Sung-Ho Cho ◽

Sung Hwan Hong ◽

Jeong Whan Han ◽

Byung Don You

Keyword(s):

Numerical Simulation ◽

Flow Pattern ◽

Model Experiment ◽

Central Area ◽

Side Wall ◽

Slag Layer ◽

Flow Patterns ◽

Water Model ◽

Slag Viscosity ◽

Mixing Behavior

Flow patterns and mixing behaviors in a gas stirred steelmaking ladle with a slag layer were discussed using a water model experiment as well as a numerical simulation. While the water model experiment was performed to investigate the effect of slag on the mixing behavior in ladle, the numerical simulation was carried out to figure out the flow pattern in ladle with a slag layer. Slag viscosity and its thickness in ladle were considered as major variables. It was found that a slag layer made a great change in the flow pattern in ladle, which, in turn, affected on the mixing behavior in ladle. A flow pattern without a slag layer showed that rising bubbles eventually made a recirculation loop at the central area of the ladle and this flow pattern was regarded as a favorable flow pattern for the better mixing behavior. However, a flow pattern with a slag layer showed distorted and localized recirculating loop near side wall below slag layer. This eventually gave a longer mixing time in ladle with a slag layer. Moreover, as the gas flow rate increases, slag existing on top of the ladle was found to be entrained into the melt. Slag viscosity and its thickness were found to be major variables affecting the behavior of slag entrainment. Lower the slag viscosity and thicker the slag layer, much more slag on top of the melt was entrained into the melt.

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Effect of Tooth Bending Damage on the Leakage of Straight-Through Labyrinth Seals

Volume 2: Fora ◽

10.1115/fedsm2005-77455 ◽

2005 ◽

Cited By ~ 1

Author(s):

Jinming Xu ◽

Matthew S. Ambrosia ◽

David L. Rhode

Keyword(s):

Flow Pattern ◽

High Reynolds Number ◽

Labyrinth Seal ◽

Quantitative Information ◽

Radial Clearance ◽

Labyrinth Seals ◽

Wall Functions ◽

Broad Variety ◽

Volume Algorithm ◽

High Reynolds

Unavoidable rotordynamic impacting on labyrinth seal teeth sometimes occurs when centrifugal compressors, for example, undergo transients. Consequently, the labyrinth seal teeth are damaged or disfigured in various ways when the surface opposite to the teeth is non-abradable. Thus far, no quantitative information concerning the effect on seal leakage is available. The present work focuses on the effect of seal leakage due to such permanently bent labyrinth seal teeth. The investigation was done numerically by solving the 2-D, axisymmetric RANS equations with a finite-volume algorithm. The high-Reynolds number k-ε turbulence model was used with standard wall functions. A broad variety of tooth seal bending was studied by varying the bending curvature and the length of bending, as well as the after-bend tooth radial clearance. The results show that the bending damage drastically affects the leakage as well as the flow pattern. This is due largely to the altered clearance caused by the bending. However, other bending factors, such as the bending curvature and the percentage of tooth length that is bent, also contribute to the change of leakage and flow pattern.

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Stereo-PIV Measurements of Turbulent Swirling Flow Inside a Pipe

Volume 2: Fluid Mechanics; Multiphase Flows ◽

10.1115/fedsm2020-20064 ◽

2020 ◽

Author(s):

Ayesha Almheiri ◽

Lyes Khezzar ◽

Mohamed Alshehhi ◽

Saqib Salam ◽

Afshin Goharzadeh

Keyword(s):

Swirling Flow ◽

Reverse Flow ◽

Tangential Velocity ◽

Circular Disk ◽

Pipe Diameter ◽

Working Fluid ◽

Complex Flow ◽

Mean Velocity ◽

Radial Profiles ◽

The Mean

Abstract Stereo-PIV is used to map turbulent strongly swirling flow inside a pipe connected to a closed recirculating system with a transparent test section of 0.6 m in length and a pipe diameter of 0.041 m. The Perspex pipe was immersed inside a water trough to reduce the effects of refraction. The working fluid was water and the Reynolds number based on the bulk average velocity inside the pipe and pipe diameter was equal to 14,450. The turbulent flow proceeds in the downstream direction and interacts with a circular disk. The measurements include instantaneous velocity vector fields and radial profiles of the mean axial, radial and tangential components of the velocity in the regions between the swirler exit and circular disk and around this later. The results for mean axial velocity show a symmetric behavior with a minimum reverse flow velocity along the centerline. As the flow developed along the pipe’s length, the intensity of the reversed flow was reduced and the intensity of the swirl decays. The mean tangential velocity exhibits a Rankine-vortex distribution and reached its maximum around half of the pipe’s radius. As the flow approaches the disk, the flow reaches stagnation and a complex flow pattern of vortices is formed. The PIV results are contrasted with LDV measurements of mean axial and tangential velocity. Good agreement is shown over the mean velocity profiles.

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Mixing and Combustion Improvement Using Jet Injection Into Swirling Flowfields

Energy Conversion ◽

10.1115/imece2002-39600 ◽

2002 ◽

Author(s):

David G. Lilley

Keyword(s):

Research Program ◽

Swirling Flow ◽

Three Dimensional ◽

Computer Code ◽

Theoretical Research ◽

Mixing Efficiency ◽

Jet Injection ◽

Mean Velocity ◽

Turbulence Data ◽

Secondary Injection

The aerodynamics benefits of lateral jet injection into swirling crossflow have long been recognized and used by combustion engineers. Studies are reported here on experimental and theoretical research on lateral jet injection into typical combustor flowfields for low-speed turbulent swirling flow conditions in the absence of combustion. The main flow is air in a round cross-sectioned plexiglass tube. The degree of swirl can be varied by varying the angles of the blades of an annular swirler, located upstream of the test section. Lateral jet injection is normal to the main airflow, from round-sectioned nozzles. Either a single lateral jet or two diametrically opposed jets are used for this secondary injection of air into the main airflow. The principal aim is to investigate the trajectory, penetration and mixing efficiency of the lateral injection. Flow visualization with helium-filled soap bubbles and multi-spark ionized path techniques, five-hole pitot probe time-mean velocity measurements, and single-wire time-mean velocity and turbulence data (normal and shear stress) have been obtained in the experimental research program. A fully three-dimensional computer code with two-equation turbulence model has been developed and used in the theoretical research program.

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