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Aerospace Propulsion: Transverse Jet Control

Propulsion: Pulse Detonation Wave Engine Simulation

Alternative Fuels: Acoustically Coupled Droplet Combustion Control

Hypersonic Flight Testing: Phoenix Testbed

Aerospace Safety: Hydrogen Leak Detection

Combustion Generated Air Pollutants: Lobed Fuel Injector

Hazardous waste Incineration: Resonant Dump Combustor

Aerospace Propulsion: In-flight Imaging of Transverse Jets


Researchers: Prof. Ann Karagozian, Prof. Robert M'Closkey, Prof. Luca Cortelezzi (McGill Univ.), Prof. Robert Kelly, Daniel Getsinger (grad), Cory Hendrickson (grad), Levon Gevokyan (grad), Jennifer Smolke (undergrad)

Former Researchers: Kevin Canzonieri (grad), Dr. Juliett Davitian (grad), Sevan Megerian (grad), Dr. Leonardo Alves (grad), Marcus George (grad), Steve Shapiro (grad), Jonathan King (grad), Dr. Thierry Schuller (grad, Ecole Centrale de Paris), Robert Lobbia (undergrad), Stepan Shahinian (undergrad), Kristy Dalrymple (undergrad), Priya Sheth (undergrad), Rebekah Tanimoto (undergrad), Tom Berger (undergrad), Jeremy Ma (undergrad), Dr. Yen-Cheng Chen (postdoc)

Research Supported By:

 

National Science Foundation

and

Air Force Office of Scientific Research

and

NASA Dryden

 
 

Smoke visualization of the transverse jet with square wave forcing.

  Julliete Davitian
 

Julliete Davitian

This project involves examination of the fundamental stability characteristics of the transverse jet, a flowfield which may be applied to fuel injection as well as dilution air injection in gas turbine engines, and which can potentially be controlled via active means so as to improve engine efficiency and reduce emissions. Current activities involve: 1) experiments on gas phase jets in crossflow, including instability characterization for equidensity and low density jets. 2) development of control strategies for optimization of jet behavior. 3) linear stability analysis as well as full 3D DNS of non-reactive transverse jets, performed by Prof. Krishnan Mahesh of the University of Minnesota, and 4) planer laser induced flourescense (PLIF) imaging and particle image velocimetry to explore flow and mixing characteristics.

The UCLA combustion laboratory's experiment setup for this project includes a low speed wind tunnel, and a range of alternative jet nozzles (both flush and elevated with respect to the lower tunnel wall). The data acquisition system allows for accurate system identification as well as open and closed loop control. A spectrum analyzer is used to extract frequency response of the input signal (speaker voltage) over the output signal (jet velocity). These Bode plots are used to create a plant model of the pulsed jet in crossflow. With the knowledge of the plant model an inverted model is used to create a compensator that gives a new compensated system Bode plot that is both flat in magnitude and matched in phase. The compensator allows us to explore different temporal waveforms (square wave, sine wave) for transverse jet forcing, with a range of operating conditions.  Optimization of jet forcing conditions to achieve desired flow features (penetration, spread, etc.) is also being explored.  More recent studies have focused on an exploration of transverse jet nearfield upstream shear layer instabilities, which vary significantly depending on the jet-to-crossflow velocity ratio R.  These studies are being conducted via gas phase experiments in the above-mentioned wind tunnel, via linear stability analysis (with discontinuous and continuous base flows for the transverse jet), and via full 3D transient Navier-Stokes simulations. 

 

 

 

 

Publications:

  1. Scalar and Velocity Field Measurements in Acoustically Excited Variable Density Transverse Jets, Getsinger, D., Gevorkyan, L., Hendrickson, C., Smith, O. I., and Karagozian, A. R., Paper AIAA-2012-1225, 50th AIAA Aerospace Sciences Meeting, Nashville, TN, January 9-12, 2012.

  2. Transition to Self-Excited Oscillations in Low Density Transverse Jet Shear Layers, Getsinger, D., Hendrickson, C., and Karagozian, A. R., Paper AIAA-2011-0040, 49th AIAA Aerospace Sciences Meeting, Orlando, FL, January 4-7, 2011.

  3. Transition to Global Instability in Transverse Jet Shear Layers, Davitian, J., Getsinger, D., Hendrickson, C., and Karagozian, A. R., Journal of Fluid Mechanics, Vol. 661, pp. 294-315, 2010.

  4. Strategic Control of Transverse Jet Shear Layer Instabilities, Davitian, J., Hendrickson, C., Getsinger, D., M'Closkey, R. T., and Karagozian, A. R., AIAA Journal, Vol. 48, No. 9, pp. 2145-2156, 2010 (doi: 10.2514/1.51248).

  5. Transverse Jets and their Control, Karagozian, A. R., Progress in Energy and Combustion Science (invited); 36(5), pp. 531-553, 2010 (http://dx.doi.org/10.1016/j.pecs.2010.01.001).

  6. Shear Layer Instabilities in Low Density Jets in Crossflow, Canzonieri, K., Getsinger, D., Hendrickson, C., Smith, O. I., and Karagozian, A. R., Paper 09F-17, Western States Section/The Combustion Institute Fall Meeting, UC Irvine, October, 2009.

  7. Transverse Jet Shear Layer Instabilities. Part II: Linear Analysis for Large Jet-to-Crossflow Velocity Ratios, Alves, L. S. de B., Kelly, R. E., and Karagozian, A. R., Journal of Fluid Mechanics, Vol. 602, pp. 383-401, 2008.

  8. Controlled Excitation of Transverse Jet Shear Layer Instabilities, Davitian, J., Hendrickson, C., Getsinger, D., M'Closkey, R. T.., and Karagozian, A. R., Western States Section/The Combustion Institute Spring Meeting, USC, Paper 08S-24, March, 2008.

  9. Strategic Control of Transverse Jet Flows, Davitian, J., Rodriguez, E., Hendrickson, C., M’Closkey, R. T., and Karagozian, A. R., 46th AIAA Aerospace Sciences Meeting, AIAA Paper AIAA-2008-0741, January, 2008.

  10. Transverse Jet Shear Layer Instabilities. Part I: Experimental Studies, Megerian, S., Davitian, J., Alves, L. S. de B., and Karagozian, A. R., Journal of Fluid Mechanics, Vol. 593, pp. 93-129, 2007.

  11. Local Stability Analysis of an Inviscid Transverse Jet, 3. Alves, L. S. de B., Kelly, R. E., and Karagozian, A. R., Journal of Fluid Mechanics, Vol. 581, pp. 401-418, 2007.

  12. Optimization of Controlled Jets in Crossflow, Shapiro, S., King, J., M'Closkey, R. T, and Karagozian, A. R., AIAA Journal, Vol. 44, No. 6, pp. 1292-1298, 2006.

  13. Linear Stability Analysis of Jets in Crossflow, Alves, L. S. de B., Kelly, R. E., and Karagozian, A. R., 43rd AIAA Aerospace Sciences Meeting, AIAA Paper AIAA-2005-1118, January, 2005.

  14. Evolution of Shear Layer Instabilities in the Transverse Jet, Megerian, S. and Karagozian, A. R., 43rd AIAA Aerospace Sciences Meeting, AIAA Paper AIAA-2005-0142, January, 2005.

  15. Control of Vorticity Generation in an Acoustically Excited Jet in Crossflow, Karagozian, A. R., Megerian, S., Alves, L, George, M., Kelly, R. E., and M'Closkey, R. T., 43rd AIAA Aerospace Sciences Meeting, Invited AIAA Paper 2005-0303, January, 2005 .

  16. Evolution of Shear Layer Instabilities in the Transverse Jet, Megerian, S. and Karagozian, A. R., AIAA Region VI Student Conference, UCLA, AIAA student paper, FIRST PLACE WINNER M.S. student division, April, 2004.

  17. Manipulation and Control of Transverse Jets, Karagozian, A. R., Cortelezzi, L., and Soldati, A., eds., CISM Courses and Lectures No. 439, Springer-Wein New York, 2003.

  18. Background on and Applications of Jets in Crossflow, in Manipulation and Control of Transverse Jets, Karagozian, A. R., CISM Courses and Lectures No. 439, Springer-Wein New York, 2003

  19. Jets Injected Normally into Compressible Crossflow, in Manipulation and Control of Transverse Jets, Karagozian, A. R., Wang, K. S. C., and Smith, O. I., CISM Courses and Lectures No. 439, Springer-Wein New York, 2003.

  20. Three-Dimensional Vortex Modeling of Unforced Transverse Jets, in Manipulation and Control of Transverse Jets, Cortelezzi, L. and Karagozian, A. R., CISM Courses and Lectures No. 439, Springer-Wein New York, 2003.

  21. Active Control of Jets in Crossflow, in Manipulation and Control of Transverse Jets, Karagozian, M'Closkey, R. T., King, J. M., Cortelezzi, L., and Karagozian, A. R., CISM Courses and Lectures No. 439, Springer-Wein New York, 2003.

  22. A Framework to Design Controllers for Engineering Applications of Transverse Jets, in Manipulation and Control of Transverse Jets, Cortelezzi, L., M’Closkey, R. T., and Karagozian, A. R., CISM Courses and Lectures No. 439, Springer-Wein New York, 2003

  23. The Actively Controlled Jet in Crossflow, R.T. M'Closkey, J. King, L. Cortelezzi, A.R. Karagozian, Journal of Fluid Mechanics, Vol. 452, No. 1, p. 325, February, 2002.

  24. On the Formation of the Counter-Rotating Vortex Pair in Transverse Jets, Cortelezzi, L. and Karagozian, A. R., Journal of Fluid Mechanics, Vol. 446, pp. 347-373, November, 2001.

  25. Actively Controlled Transverse Gas Injection, L. Cortelezzi, J. King, R. Lobbia, R.T. M'Closkey, A.R. Karagozian, IEEE Conference on Decision and Control, Invited Paper CDC00-INV4905, December, 2000.

 

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