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

Investigation of Air Injection and Cavity Size Within a Circumferential Combustor to Increase G-Load and Residence Time

[+] Author and Article Information
Andrew E. Cottle

Department of Aeronautics and Astronautics,
Air Force Institute of Technology,
Wright-Patterson Air Force Base, OH 45433

Marc D. Polanka

Department of Aeronautics and Astronautics,
Air Force Institute of Technology,
Wright-Patterson Air Force Base, OH, 45433

Larry P. Goss

Innovative Scientific Solutions, Inc.,
7610 McEwen Road,
Dayton, OH 45459

Corey Z. Goss

Innovative Scientific Solutions, Inc.,
7610 McEwen Road,
Dayton, OH 45459

Contributed by the Combustion and Fuels Committee of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received May 26, 2017; final manuscript received July 4, 2017; published online September 19, 2017. Editor: David Wisler. This work is in part a work of the U.S. Government. ASME disclaims all interest in the U.S. Government's contributions.

J. Eng. Gas Turbines Power 140(1), 011501 (Sep 19, 2017) (12 pages) Paper No: GTP-17-1182; doi: 10.1115/1.4037578 History: Received May 26, 2017; Revised July 04, 2017

A gas turbine combustion process subjected to high levels of centrifugal acceleration has demonstrated the potential for increased flame speeds and shorter residence times. Ultracompact combustors (UCC) invoke the high-g phenomenon by introducing air and fuel into a circumferential cavity which is recessed radially outboard with respect to the primary axial core flow. Upstream air is directed tangentially into the combustion cavity to induce bulk circumferential swirl. Swirl velocities in the cavity produce a centrifugal load on the flow that is typically expressed in terms of gravitational acceleration or g-loading. The Air Force Institute of Technology (AFIT) has developed an experimental facility in which g-loads up to 2000 times the earth’s gravitational field (“2000 g’s”) have been demonstrated. In this study, the flow within the combustion cavity is examined to determine factors and conditions which invoke responses in cavity g-loads. The AFIT experiment was modified to enable optical access into the primary combustion cavity. The techniques of particle image velocimetry (PIV) and particle streak emission velocimetry (PSEV) provided high-fidelity measurements of the velocity fields within the cavity. The experimental data were compared to a set of computational fluid dynamics (CFD) solutions. Improved cavity air and fuel injection schemes were evaluated over a range of air flows and equivalence ratios. Increased combustion stability was attained by providing a uniform distribution of cavity air drivers. Lean cavity equivalence ratios at a high total airflow resulted in higher g-loads and more complete combustion, thereby showing promise for utilization of the UCC as a main combustor.

Copyright © 2018 by ASME
Your Session has timed out. Please sign back in to continue.


Turns, S. , 2011, An Introduction to Combustion: Concepts and Applications, 3rd ed., McGraw-Hill, New York. [PubMed] [PubMed]
Erdmann, T. J. , Burrus, D. L. , Shouse, D. T. , Gross, J. T. , Neuroth, C. , and Caswell, A. W. , 2014, “ Experimental Characterization of the Reaction Zone in an Ultra-Compact Combustor,” AIAA Paper No. 2014-3630.
Cottle, A. E. , and Polanka, M. D. , 2016, “ Numerical and Experimental Results From a Common-Source High-G Ultra-Compact Combustor,” ASME Paper No. GT2016-56215.
Lewis, G. D. , 1973, “ Centrifugal-Force Effects on Combustion,” Symp. (Int.) Combust., 14(1), pp. 413–419. [CrossRef]
Lapsa, A. P. , and Dahm, W. J. A. , 2009, “ Hyperacceleration Effects on Turbulent Combustion in Premixed Step-Stabilized Flames,” Proc. Combust. Inst., 32(2), pp. 1731–1738. [CrossRef]
Zelina, J. , Sturgess, G. J. , and Shouse, D. T. , 2004, “ The Behavior of an Ultra-Compact Combustor (UCC) Based on Centrifugally-Enhanced Turbulent Burning Rates,” AIAA Paper No. 2004-3541.
Briones, A. M. , Sekar, B. , and Erdmann, T. , 2015, “ Effect of Centrifugal Force on Turbulent Premixed Flames,” ASME J. Eng. Gas Turbines Power, 137(1), p. 011501. [CrossRef]
Moenter, D. S. , 2006, “ Design and Numerical Simulation of Two Dimensional Ultra Compact Combustor Model Sections for Experimental Observation of Cavity-Vane Flow Interactions,” M.S. thesis, Wright-Patterson Air Force Base, Dayton, OH. http://www.dtic.mil/docs/citations/ADA456932
Thomas, L. M. , 2009, “ Flow Measurements Using Particle Image Velocimetry in the Ultra Compact Combustor,” M.S. thesis, Wright-Patterson Air Force Base, OH. http://www.dtic.mil/docs/citations/ADA512529
LeBay, K. D. , Hankins, T. B. , Lakusta, P. J. , Branam, R. D. , Reeder, M. F. , and Kostka, S. , 2010, “ OH-PLIF Calibration and Investigation Within the Ultra Compact Combustor,” AIAA Paper No. 2010-1330.
LeBay, K. D. , Polanka, M. D. , Reeder, M. F. , and Branam, R. D. , 2011, “ Time-Resolved Particle Image Velocimetry Investigations Within a Sectional Ultra Compact Combustor,” AIAA Paper No. 2010-895443.
LeBay, K. D. , Drenth, A. C. , Thomas, L. M. , Polanka, M. D. , Branam, R. D. , and Schmidt, J. B. , 2010, “ Characterizing the Effects of G-Loading in an Ultra Compact Combustor Via Sectional Models,” ASME Paper No. GT2010-22723.
Bohan, B. T. , and Polanka, M. D. , 2013, “ Analysis of Flow Migration in an Ultra-Compact Combustor,” ASME J. Eng. Gas Turbines Power, 135(5), p. 051502. [CrossRef]
Wilson, J. D. , Damele, C. J. , and Polanka, M. D. , 2014, “ Flame Structure Effects at High G-Loading,” ASME J. Eng. Gas Turbines Power, 136(10), p. 101502. [CrossRef]
Wilson, J. D. , and Polanka, M. D. , 2013, “ Reduction of Rayleigh Losses in a High G-Loaded Ultra Compact Combustor,” ASME Paper No. GT2013-94795.
Damele, C. J. , Polanka, M. D. , Wilson, J. D. , and Rutledge, J. L. , 2014, “ Characterizing Thermal Exit Conditions for an Ultra Compact Combustor,” AIAA Paper No. 2014-0456.
Conrad, M. M. , Wilson, J. D. , and Polanka, M. D. , 2013, “ Integration Issues of an Ultra-Compact Combustor to a Jet Turbine Engine,” AIAA Paper No. 2013-3711.
Cottle, A. E. , and Polanka, M. D. , 2015, “ Common Flow Source for a Full Annular Ultra Compact Combustor,” AIAA Paper No. 2015-0100.
Mongia, H. C. , 2008, “ Recent Progress in Comprehensive Modeling of Gas Turbine Engine Combustion,” AIAA Paper No. 2008-1445.
Hsu, M. C. , Vogiatzis, K. , and Huang, P. G. , 2003, “ Validation and Implementation of Advanced Turbulence Models in Swirling and Separated Flows,” AIAA Paper No. 2003-0766.
Celik, I . B. , Ghia, U. , Roache, P. J. , Freitas, C. J. , Coleman, H. , and Raad, P. E. , 2008, “ Procedure for Estimation and Reporting of Uncertainty Due to Discretization in CFD Applications,” ASME J. Fluid Eng., 130(7), p. 078001. [CrossRef]


Grahic Jump Location
Fig. 3

AFIT common-source test hardware illustration cutaway (left) and full view (right)

Grahic Jump Location
Fig. 2

AFIT discrete-source hardware illustration (top) highlighting the guide vane detail and air/fuel injection ring (bottom) [14]

Grahic Jump Location
Fig. 1

AFRL UCC stability map [5]

Grahic Jump Location
Fig. 4

AFIT common-source hardware components (top) and interior detail (bottom)

Grahic Jump Location
Fig. 5

Experimental test setup from the approximate camera location; quartz window, exhaust cowling, and exhaust duct are removed

Grahic Jump Location
Fig. 6

Sample PESV image processing progression

Grahic Jump Location
Fig. 7

Computational domain (top) and axial reference positions (bottom)

Grahic Jump Location
Fig. 8

Top row: PIV results showing velocity magnitude (m/s) for conditions 1 (left), 2, and 3. Bottom row: CFD results with approximate matching region highlighted (identical contour levels).

Grahic Jump Location
Fig. 9

PESV results of bulk velocity magnitude (m/s) for constant ϕcav=0.94 (top row) at low, mid, and high flow; and constant total inlet flow rate of 0.15 kg/s (bottom row) at ϕcav={0.75, 0.97, 1.26}

Grahic Jump Location
Fig. 10

Cavity injection scheme comparison; front view of temperature contours (K) (top), and fuel injection stream traces colored by temperature (bottom) of the old (left) and new (right) experimental configuration

Grahic Jump Location
Fig. 16

Velocity vectors (aft view) colored by tangential velocity for, from top to bottom, cases med-lean, med-rich, high-lean, and high-rich

Grahic Jump Location
Fig. 17

Velocity vectors (aft view) colored by temperature (K) for the high-lean case at fore (top), mid, and aft cavity axial positions

Grahic Jump Location
Fig. 11

Single-point fuel injection stream traces colored by temperature (K); midlean (top-left), med-rich (top-right), high-lean (bottom-left), and high-rich (bottom-right)

Grahic Jump Location
Fig. 12

Local equivalence ratio contours in the combustion cavity (position C2) for the high-flow case at lean (left) and rich overall cavity equivalence ratios

Grahic Jump Location
Fig. 13

Cut planes at position D1 of temperature (top) and local equivalence ratio (bottom) for lean (left) and rich (right) flows

Grahic Jump Location
Fig. 14

Radial profiles of circumferentially averaged temperatures in the combustion cavity

Grahic Jump Location
Fig. 15

Radial profiles of circumferentially averaged g-loads in the combustion cavity




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