Purge-Mainstream Interactions in a Turbine Stage With Rotor Endwall Contouring

Alexander Mesny; Oliver J. Pountney; James A. Scobie; Y. S. Li; Carl M. Sangan

doi:10.1115/GT2023-103877

Purge-Mainstream Interactions in a Turbine Stage With Rotor Endwall Contouring

Alexander Mesny, Oliver J. Pountney, James A. Scobie, Y. S. Li, Carl M. Sangan

Research output: Chapter or section in a book/report/conference proceeding › Chapter in a published conference proceeding

Abstract

Purge flows are prevalent in modern gas turbine design allowing for increased turbine entry temperatures. The purge flow passes through a rim seal and interacts with the mainstream flow, modifying the blade secondary flow structures and reducing stage efficiency. These structures may be controlled using End Wall Contouring (EWC), though experimental demonstration of their benefit is seldom reported in the literature. The optically accessible turbine at the University of Bath was designed to directly measure and visualize the flow field within the blade passage for a rotor with EWC.

The single-stage turbine enables phase-locked flow field measurements with volumetric Particle Image Velocimetry (PIV). Purge flow was supplied to investigate a range of operating conditions in which the secondary flow structures were modified. The modular turbine rotor allowed for expedient change of a bladed ring, or bling, featuring non-axisymmetric EWC.

The identified secondary flow structures were the Pressure-Side leg of the Horse Shoe Vortex (PS-HSV) and an Egress Vortex (EV) of concurrent rotational direction. An increase in purge flow rate monotonically shifted the EV toward the suction-side (SS) of the adjacent blade. The migration of the PS-HSV towards the SS caused the two aforementioned vortices to merge.

The EWC rotor design included a Leading-Edge (LE) feature to alter the PS-HSV, and a trough to guide the EV low spanwise in the passage and maintain displacement from the adjacent suction side. The EWC rotor was found to be effective at altering the formation and positioning of the secondary flow structures at a range of purge flow conditions.

Original language	English
Title of host publication	Turbomachinery - Axial Flow Turbine Aerodynamics
Subtitle of host publication	Axial Flow Turbine Aerodynamics
Number of pages	13
Volume	13B
ISBN (Electronic)	9780791887097
DOIs	https://doi.org/10.1115/GT2023-103877
Publication status	Published - 28 Sept 2023
Event	ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition - Boston, Massachusetts, USA Duration: 26 Jun 2023 → 30 Jun 2023

Publication series

Name	Proceedings of the ASME Turbo Expo
Volume	13B

Conference

Conference	ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition
Period	26/06/23 → 30/06/23

Bibliographical note

Publisher Copyright:
Copyright © 2023 by ASME.

Funding

The authors would like to thank Siemens Energy Industrial Turbomachinery Ltd. and the Engineering & Physical Sciences Research Council (EPSRC) for their financial support (grant EP/M026345/1). The experimental studies made use of the Versatile Fluid Measurement System enabled through EPSRC strategic equipment grant funding; EP/M000559/1 and EP/K040391/1. The authors thank Andrew Langley and Jim Cansell of the Department of Mechanical Engineering at the University of Bath for their expert technical support in this work. The content of this paper is copyrighted by Siemens Energy Global GmbH & Co. KG and is licensed to ASME for publication and distribution only. Any inquiries regarding permission to use the content of this paper, in whole or in part, for any purpose must be addressed to Siemens Energy Industrial Turbomachinery Limited, directly. The authors would like to thank Siemens Energy Industrial Turbomachinery Ltd. and the Engineering & Physical Sciences Research Council (EPSRC) for their financial support (grant EP/M026345/1). The experimental studies made use of the Versatile Fluid Measurement System enabled through EPSRC strategic equipment grant funding; EP/M000559/1 and EP/K040391/1. The authors thank Andrew Langley and Jim Cansell of the Department of Mechanical Engineering at the University of Bath for their expert technical support in this work.

Funders	Funder number
Andrew Langley
Siemens Energy Global GmbH & Co
Siemens Energy Industrial Turbomachinery Limited
Siemens Energy Industrial Turbomachinery Ltd.
Engineering and Physical Sciences Research Council	EP/K040391/1, EP/M026345/1, EP/M000559/1

Keywords

Axial Turbine
Endwall Contouring
Purge
Secondary Flows
Volumetric Velocimetry

ASJC Scopus subject areas

General Engineering

Access to Document

10.1115/GT2023-103877

Cite this

Purge-Mainstream Interactions in a Turbine Stage With Rotor Endwall Contouring. / Mesny, Alexander ; Pountney, Oliver J.; Scobie, James A. et al.
Turbomachinery - Axial Flow Turbine Aerodynamics: Axial Flow Turbine Aerodynamics. Vol. 13B 2023. v13bt30a040 (Proceedings of the ASME Turbo Expo; Vol. 13B).

Research output: Chapter or section in a book/report/conference proceeding › Chapter in a published conference proceeding

Mesny, A , Pountney, OJ , Scobie, JA, Li, YS & Sangan, CM 2023, Purge-Mainstream Interactions in a Turbine Stage With Rotor Endwall Contouring. in Turbomachinery - Axial Flow Turbine Aerodynamics: Axial Flow Turbine Aerodynamics. vol. 13B, v13bt30a040, Proceedings of the ASME Turbo Expo, vol. 13B, ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition, 26/06/23. https://doi.org/10.1115/GT2023-103877

@inproceedings{50b92a64ea094248b248dcbf4b0610ad,

title = "Purge-Mainstream Interactions in a Turbine Stage With Rotor Endwall Contouring",

abstract = "Purge flows are prevalent in modern gas turbine design allowing for increased turbine entry temperatures. The purge flow passes through a rim seal and interacts with the mainstream flow, modifying the blade secondary flow structures and reducing stage efficiency. These structures may be controlled using End Wall Contouring (EWC), though experimental demonstration of their benefit is seldom reported in the literature. The optically accessible turbine at the University of Bath was designed to directly measure and visualize the flow field within the blade passage for a rotor with EWC.The single-stage turbine enables phase-locked flow field measurements with volumetric Particle Image Velocimetry (PIV). Purge flow was supplied to investigate a range of operating conditions in which the secondary flow structures were modified. The modular turbine rotor allowed for expedient change of a bladed ring, or bling, featuring non-axisymmetric EWC.The identified secondary flow structures were the Pressure-Side leg of the Horse Shoe Vortex (PS-HSV) and an Egress Vortex (EV) of concurrent rotational direction. An increase in purge flow rate monotonically shifted the EV toward the suction-side (SS) of the adjacent blade. The migration of the PS-HSV towards the SS caused the two aforementioned vortices to merge.The EWC rotor design included a Leading-Edge (LE) feature to alter the PS-HSV, and a trough to guide the EV low spanwise in the passage and maintain displacement from the adjacent suction side. The EWC rotor was found to be effective at altering the formation and positioning of the secondary flow structures at a range of purge flow conditions.",

keywords = "Axial Turbine, Endwall Contouring, Purge, Secondary Flows, Volumetric Velocimetry",

author = "Alexander Mesny and Pountney, {Oliver J.} and Scobie, {James A.} and Li, {Y. S.} and Sangan, {Carl M.}",

note = "Publisher Copyright: Copyright {\textcopyright} 2023 by ASME.; ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition ; Conference date: 26-06-2023 Through 30-06-2023",

year = "2023",

month = sep,

day = "28",

doi = "10.1115/GT2023-103877",

language = "English",

isbn = "978-0-7918-8709-7",

volume = "13B",

series = "Proceedings of the ASME Turbo Expo",

booktitle = "Turbomachinery - Axial Flow Turbine Aerodynamics",

}

TY - GEN

T1 - Purge-Mainstream Interactions in a Turbine Stage With Rotor Endwall Contouring

AU - Mesny, Alexander

AU - Pountney, Oliver J.

AU - Scobie, James A.

AU - Li, Y. S.

AU - Sangan, Carl M.

PY - 2023/9/28

Y1 - 2023/9/28

N2 - Purge flows are prevalent in modern gas turbine design allowing for increased turbine entry temperatures. The purge flow passes through a rim seal and interacts with the mainstream flow, modifying the blade secondary flow structures and reducing stage efficiency. These structures may be controlled using End Wall Contouring (EWC), though experimental demonstration of their benefit is seldom reported in the literature. The optically accessible turbine at the University of Bath was designed to directly measure and visualize the flow field within the blade passage for a rotor with EWC.The single-stage turbine enables phase-locked flow field measurements with volumetric Particle Image Velocimetry (PIV). Purge flow was supplied to investigate a range of operating conditions in which the secondary flow structures were modified. The modular turbine rotor allowed for expedient change of a bladed ring, or bling, featuring non-axisymmetric EWC.The identified secondary flow structures were the Pressure-Side leg of the Horse Shoe Vortex (PS-HSV) and an Egress Vortex (EV) of concurrent rotational direction. An increase in purge flow rate monotonically shifted the EV toward the suction-side (SS) of the adjacent blade. The migration of the PS-HSV towards the SS caused the two aforementioned vortices to merge.The EWC rotor design included a Leading-Edge (LE) feature to alter the PS-HSV, and a trough to guide the EV low spanwise in the passage and maintain displacement from the adjacent suction side. The EWC rotor was found to be effective at altering the formation and positioning of the secondary flow structures at a range of purge flow conditions.

AB - Purge flows are prevalent in modern gas turbine design allowing for increased turbine entry temperatures. The purge flow passes through a rim seal and interacts with the mainstream flow, modifying the blade secondary flow structures and reducing stage efficiency. These structures may be controlled using End Wall Contouring (EWC), though experimental demonstration of their benefit is seldom reported in the literature. The optically accessible turbine at the University of Bath was designed to directly measure and visualize the flow field within the blade passage for a rotor with EWC.The single-stage turbine enables phase-locked flow field measurements with volumetric Particle Image Velocimetry (PIV). Purge flow was supplied to investigate a range of operating conditions in which the secondary flow structures were modified. The modular turbine rotor allowed for expedient change of a bladed ring, or bling, featuring non-axisymmetric EWC.The identified secondary flow structures were the Pressure-Side leg of the Horse Shoe Vortex (PS-HSV) and an Egress Vortex (EV) of concurrent rotational direction. An increase in purge flow rate monotonically shifted the EV toward the suction-side (SS) of the adjacent blade. The migration of the PS-HSV towards the SS caused the two aforementioned vortices to merge.The EWC rotor design included a Leading-Edge (LE) feature to alter the PS-HSV, and a trough to guide the EV low spanwise in the passage and maintain displacement from the adjacent suction side. The EWC rotor was found to be effective at altering the formation and positioning of the secondary flow structures at a range of purge flow conditions.

KW - Axial Turbine

KW - Endwall Contouring

KW - Purge

KW - Secondary Flows

KW - Volumetric Velocimetry

UR - http://www.scopus.com/inward/record.url?scp=85177469714&partnerID=8YFLogxK

U2 - 10.1115/GT2023-103877

DO - 10.1115/GT2023-103877

M3 - Chapter in a published conference proceeding

SN - 978-0-7918-8709-7

VL - 13B

T3 - Proceedings of the ASME Turbo Expo

BT - Turbomachinery - Axial Flow Turbine Aerodynamics

T2 - ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition

Y2 - 26 June 2023 through 30 June 2023

ER -

Purge-Mainstream Interactions in a Turbine Stage With Rotor Endwall Contouring

Abstract

Publication series

Conference

Bibliographical note

Funding

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Improving Turbine Efficiency by Combining the Effects of Rim Seals and End-Wall Contours in the Presence of Purge Flow

Cite this

Purge-Mainstream Interactions in a Turbine Stage With Rotor Endwall Contouring

Abstract

Publication series

Conference

Bibliographical note

Funding

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Projects

Improving Turbine Efficiency by Combining the Effects of Rim Seals and End-Wall Contours in the Presence of Purge Flow

Cite this