0
Research Papers

Blade Triggered Excitation of Periodically Unsteady Impinging Jets for Efficient Turbine Liner Segment Cooling

[+] Author and Article Information
Christian Scherhag

Institute of Gas Turbines
and Aerospace Propulsion,
Technische Universität Darmstadt,
Otto-Berndt-Str. 2,
Darmstadt 64287, Germany
e-mail: scherhag@glr.tu-darmstadt.de

Jan Paul Geiermann, Fabian Wartzek, Heinz-Peter Schiffer

Institute of Gas Turbines
and Aerospace Propulsion,
Technische Universität Darmstadt,
Otto-Berndt-Str. 2,
Darmstadt 64287, Germany

Contributed by the International Gas Turbine Institute (IGTI) of ASME for publication in the JOURNAL OF TURBOMACHINERY. Manuscript received November 9, 2015; final manuscript received November 13, 2015; published online January 20, 2016. Editor: Kenneth C. Hall.

J. Turbomach 138(5), 051005 (Jan 20, 2016) (10 pages) Paper No: TURBO-15-1254; doi: 10.1115/1.4032145 History: Received November 09, 2015; Revised November 13, 2015

In the present study, an application for efficient cooling of turbine liner segments employing pulsating impinging jets was investigated. A combined numerical and experimental study was conducted to evaluate the design of a case cavity device which utilizes the periodically unsteady pressure distribution caused by the rotor blades to excite a pulsating impinging jet. Through an opening between the main annulus and a case cavity, pressure pulses from the rotor blades propagated into this cavity and caused a strong pressure oscillation inside. The unsteady computational fluid dynamics (CFD) results were in good qualitative agreement with the measurement data obtained using high-frequency pressure transducers and hot wire anemometry. Furthermore, the numerical study revealed the formation of distinct toroidal vortex structures at the nozzle outlet as a result of the jet pulsation. Within the scope of the measurements, the influence of the operating point on the pressure propagation inside the cavity was investigated. The dependence of shape and amplitude of the pressure oscillation on engine speed and stage pressure ratio was found to be in accordance with an analytical consideration.

Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Darmstadt Transonic Compressor

Grahic Jump Location
Fig. 2

Compressor stage and investigated case cavity device

Grahic Jump Location
Fig. 3

Dimensions of the cavity device and schematic illustration of cooling air flow and pressure oscillation

Grahic Jump Location
Fig. 4

Instrumentation applied to the inner cavity

Grahic Jump Location
Fig. 5

Close-up view of the computational domain

Grahic Jump Location
Fig. 6

Ratio of grid spacing to Kolmogorov length scale in an axial slice through the cavity device

Grahic Jump Location
Fig. 7

Pressure distribution in the cavity device

Grahic Jump Location
Fig. 8

Frequency spectrum of the pressure signal monitored in the transient CFD computation close to the opening between main annulus and inner cavity

Grahic Jump Location
Fig. 9

Velocity variation over time at the nozzle outlet

Grahic Jump Location
Fig. 10

Visualization of vortex structures using isosurfaces of q = 9 × 109 s−2 colored by vorticity

Grahic Jump Location
Fig. 11

Frequency spectrum encompassing the recorded pressure signals of all 19 pressure transducers

Grahic Jump Location
Fig. 12

Schematic illustration of the data averaging procedure

Grahic Jump Location
Fig. 13

Unsteady pressure distribution: experimental results above, CFD results below

Grahic Jump Location
Fig. 14

Comparison of experimental and numerical results for the velocity fluctuation at the nozzle outlet

Grahic Jump Location
Fig. 15

Analytical solution for the shift of the central pressure maximum following Eq. (14)

Grahic Jump Location
Fig. 16

Influence of engine speed and pressure ratio on the shift of the central pressure maximum

Grahic Jump Location
Fig. 17

Relation between pressure amplitude and velocity fluctuation for different pressure ratios

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