0
Research Papers: Gas Turbines: Combustion, Fuels, and Emissions

Influence of Large Wake Disturbances Shed From the Combustor Wall on the Leading Edge Film Cooling

[+] Author and Article Information
Cosimo Maria Mazzoni

Mem. ASME
Osney Thermo-Fluids Laboratory,
Department of Engineering Science,
Oxford University,
Southwell Building, Osney Mead,
Oxford OX2 0DP, UK
e-mail: cosimo.mazzoni@eng.ox.ac.uk

Christian Klostermeier

The Boston Consulting Group GmbH,
Am Stadttor 1,
Dusseldorf 40219, Germany
e-mail: klostermeier.christian@bcg.com

Budimir Rosic

Mem. ASME
Osney Thermo-Fluids Laboratory,
Department of Engineering Science,
Oxford University,
Southwell Building, Osney Mead,
Oxford OX2 0DP, UK
e-mail: budimir.rosic@eng.ox.ac.uk

Contributed by the Combustion and Fuels Committee of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received January 13, 2014; final manuscript received January 26, 2014; published online March 7, 2014. Editor: David Wisler.

J. Eng. Gas Turbines Power 136(8), 081503 (Mar 07, 2014) (13 pages) Paper No: GTP-14-1027; doi: 10.1115/1.4026803 History: Received January 13, 2014; Revised January 26, 2014

The first vane leading edge film cooling is challenging because of the highest thermal load and the complex flow interaction between the hot mainstream gas and the coolant flow. This interaction varies significantly from the stagnation region to the regions of high curvature and acceleration further downstream. Additionally, in industrial gas turbines with multiple combustor chambers around the annulus the first vane leading edges may also be exposed to large wake disturbances shed from the upstream combustor walls. The influence of these vortical structures on the first vane leading edge film cooling is numerically analyzed in this paper. In order to assess the capabilities of the flow solver TBLOCK to simulate these complex interactions an experimental test case is modeled numerically. The test case is available in the open literature and consists of a cylindrical leading edge and two rows of film cooling holes representative of industrial practice. A LES turbulence modeling strategy with the WALE subgrid scale (SGS) model is applied and compared against experimental results. Based on this validation it is decided to analyze also the wake–leading edge interaction, dominated by large scale unsteady vortical structures, using the same WALE subgrid scale LES model. The initial flow domain with the cylindrical leading edge and cooling holes is extended to incorporate the effect of the combustor wall, which is modeled as a flat plate with a square trailing edge. The location and the size of the plate are scaled to be representative of industrial practice: the plate is located upstream from the leading edge at a distance twice the leading edge diameter, and the thickness of the plate is one half of the leading edge diameter. Two different clockwise positions of the vertical combustor wall model were investigated and compared with the datum configuration: the former where the axis of the plate and the leading edge are aligned (central wake location), the latter with the combustor wall circumferentially shifted up by a quarter of the leading edge diameter (circumferentially shifted wake location). Numerical predictions show that the shed vortices from the combustor wall trailing edge have a highly detrimental effect on the leading edge film cooling by periodically removing the coolant flow from the leading edge surface. This results in an increased unsteady thermal load. These negative effects are less significant in the case of circumferentially shifted wake, due to the combined action of both shed vortices.

Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Schematic of an industrial gas turbine multiple combustion system and the first turbine vane

Grahic Jump Location
Fig. 2

Schematic of the experimental setup used by Cruse et al. [3] to investigate leading edge film cooling

Grahic Jump Location
Fig. 3

Measured and predicted adiabatic cooling effectiveness contours modeling (the top wall)

Grahic Jump Location
Fig. 4

Measured and predicted nondimensional temperature distributions at x/d = 1.24 from the central line

Grahic Jump Location
Fig. 5

Measured and predicted nondimensional temperature distributions at x/d = 4.9 from the central line

Grahic Jump Location
Fig. 6

Measured and predicted nondimensional temperature distributions at x/d = 10.0 from the central line

Grahic Jump Location
Fig. 7

Coherent structures (without wake)

Grahic Jump Location
Fig. 8

Mass flow fluctuations (m/m2,mean) in time for each hole (without wake)

Grahic Jump Location
Fig. 9

Computational flow domain with the leading edge and the upstream plate—central wake position

Grahic Jump Location
Fig. 10

Instantaneous y vorticity, nondimensional temperature, vortical structures, and adiabatic cooling effectiveness on the top half of leading edge (with central wake) for three different instances in time during one trailing edge vortex shedding period

Grahic Jump Location
Fig. 11

Mass flow fluctuations (m/m2,mean) in time for each hole (with central wake)

Grahic Jump Location
Fig. 12

Predicted adiabatic cooling effectiveness contours at the leading edge top wall (without and with central wake)

Grahic Jump Location
Fig. 13

Computational flow domain with the leading edge and the upstream plate—shifted wake position

Grahic Jump Location
Fig. 14

Instantaneous y vorticity, nondimensional temperature, vortical structures, and adiabatic cooling effectiveness on the top half of leading edge (with circumferentially shifted wake) for three different instances in time during one trailing edge vortex shedding period

Grahic Jump Location
Fig. 15

Mass flow fluctuations (m/m2,mean) in time for each hole (with circumferentially shifted wake

Grahic Jump Location
Fig. 16

Predicted adiabatic cooling effectiveness contours at the leading edge top wall (with central wake and with circumferentially shifted wake)

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In