Hostname: page-component-8448b6f56d-xtgtn Total loading time: 0 Render date: 2024-04-19T02:08:25.247Z Has data issue: false hasContentIssue false

Dynamics of harmonically excited, reacting bluff body wakes near the global hydrodynamic stability boundary

Published online by Cambridge University Press:  21 August 2015

Benjamin Emerson*
Affiliation:
Department of Aerospace Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
Tim Lieuwen
Affiliation:
Department of Aerospace Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
*
Email address for correspondence: bemerson@gatech.edu

Abstract

This paper describes linear and nonlinear interactions between forced axial acoustic oscillations and the global mode of the reacting wake. This work is motivated by the problem of combustion instabilities, where acoustic oscillations associated with natural combustor modes excite hydrodynamic instabilities of the flow that, in turn, induce heat release oscillations. Wake flows with density stratification can be globally stable or unstable at high Reynolds numbers, and so the density change across the flame has significant influence on the natural flame and flow dynamics. Measurements were obtained in a facility in which flame density ratio, lip velocity and forcing frequency are independently varied using 5 kHz particle image velocimetry and Mie scattering measurements. By varying the density ratio, the hydrodynamic global mode growth rate can be systematically varied. In addition, measurements and analyses were performed where the forcing frequency is varied relative to the global mode frequency. While axial forcing excites a varicose response of the shear layers, the sinuous mode is the most rapidly growing. As expected, forcing at a frequency near the wake’s global mode frequency leads to rapid growth in vortical disturbance amplitude, and the symmetric vortices quickly stagger as they convect downstream leading to a large scale, sinuous flapping of the wake and flame. A linear, local stability analysis, together with a nonlinear analysis, help elucidate the physics that govern the vortex staggering. The study concludes with an analysis of the heat release dynamics. Significantly, the study shows that the heat release exhibits quite different sensitivities than the fluid dynamics; e.g. axial forcing of the flow near its global mode frequency leads to a reduction in heat release oscillations. This is true even though this forcing frequency maximizes the local degree of vortically induced flame flapping. Thus, the results of this study show some phenomena that contradict conventional notions, namely that conditions which align the frequency of a hydrodynamic global mode with that of an acoustic mode may lead to diminished forced heat release oscillations in bluff body combustors.

Type
Papers
Copyright
© 2015 Cambridge University Press 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Abdelkhalek, M. F., Ghoneim, Z. & Ghoniem, A. F. 2001 Numerical simulation of acoustic effect on the stability of a lean premixed combustor. In Proceedings of ICFDP7: 7th International Congress on Fluid Dynamics and Propulsion.Google Scholar
Anderson, K. R., Hertzberg, J. & Mahalingam, S. 1996 Classification of absolute and convective instabilities in premixed bluff body stabilized flames. Combust. Sci. Technol. 112, 257269.CrossRefGoogle Scholar
Barbi, C., Favier, D. P., Maresca, C. A. & Telionis, D. P. 1986 Vortex shedding and lock-on of a circular cylinder in oscillatory flow. J. Fluid Mech. 170, 527544.CrossRefGoogle Scholar
Barkley, D. 2006 Linear analysis of the cylinder wake mean flow. Europhys. Lett. 75, 750756.CrossRefGoogle Scholar
Bellows, B. D., Hreiz, A. & Lieuwen, T. 2008 Nonlinear interactions between forced and self-excited acoustic oscillations in premixed combustor. J. Propul. Power 24, 628631.CrossRefGoogle Scholar
Bishop, R. E. D. & Hassan, A. Y. 1964 The lift and drag forces on a circular cylinder oscillating in a flowing fluid. Proc. R. Soc. Lond. A 277, 5175.Google Scholar
Blevins, R. D. 1977 Flow-Induced Vibration. Van Nostrand Reinhold.Google Scholar
Boyer, L. & Quinard, J. 1990 On the dynamics of anchored flames. Combust. Flame 82, 5165.CrossRefGoogle Scholar
Cantwell, B. & Coles, D. 1983 An experimental study of entrainment and transport in the turbulent near wake of a circular cylinder. J. Fluid Mech. 136, 321374.CrossRefGoogle Scholar
Cardell, G. S.1993 Flow past a circular cylinder with a permeable wake splitter plate. PhD thesis, Pasadena, CA.Google Scholar
Chaudhuri, S., Kostka, S., Renfro, M. W. & Cetegen, B. M. 2010a Blowoff dynamics of bluff body stabilized turbulent premixed flames. Combust. Flame 157, 790802.CrossRefGoogle Scholar
Chaudhuri, S., Kostka, S., Tuttle, S. G., Renfro, M. W. & Cetegen, B. M. 2010b Blowoff dynamics of v-shaped bluff body stabilized, turbulent premixed flames in a practical scale rig. In 48th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition, 4-7 January 2010, Orlando, Florida,; Paper number AIAA 2010-1337.Google Scholar
Chrighton, D. G. 1973 Instability of an elliptic jet. J. Fluid Mech. 59, 665672.CrossRefGoogle Scholar
Cvitanovic, P. & Eckhardt, B. 1993 Symmetry decomposition of chaotic dynamics. Nonlinearity 6, 277311.CrossRefGoogle Scholar
Durst, F., Melling, A. & Whitelaw, J. H.1976 Principles and practice of laser-doppler anemometry, NASA Tech. Rep. 47019, STI/Rrecon A.Google Scholar
Emerson, B., Mondragon, U., Acharya, V., Shin, D.-H., Brown, C., McDonell, V. & Lieuwen, T. 2013 Velocity and flame wrinkling characteristics of a transversely forced, bluff body stabilized flame. Part I: experiments and data analysis. Combust. Sci. Technol. 185, 10561076.CrossRefGoogle Scholar
Emerson, B., O’Connor, J., Juniper, M. & Lieuwen, T. 2012 Density ratio effects on reacting bluff-body flow field characteristics. J. Fluid Mech. 706, 219250.CrossRefGoogle Scholar
Ferguson, N. & Parkinson, G. V. 1967 Surface and wake flow phenomena of the vortex-excited oscillation of a circular cylinder. J. Engng Ind. 89, 831838.CrossRefGoogle Scholar
Fincham, A. M. & Spedding, G. R. 1997 Low cost, high resolution dpiv for measurement of turbulent fluid flow. Exp. Fluids 23, 449462.CrossRefGoogle Scholar
Gaydon, A. G. & Wolfhard, H. G. 1970 Flames: Their Structure, Radiation and Temperature. Chapman & Hall.Google Scholar
Godreche, C. & Manneville, P. 1998 Hydrodynamics and Nonlinear Instabilities. Cambridge University Press.CrossRefGoogle Scholar
Griffin, O. M. & Ramberg, S. E. 1976 Vortex shedding from a cylinder vibrating in line with an incident uniform flow. J. Fluid Mech. 75, 257271.CrossRefGoogle Scholar
Hermanson, J. C. & Dimotakis, P. E. 1989 Effects of heat release in a turbulent, reacting shear layer. J. Fluid Mech. 199, 333375.CrossRefGoogle Scholar
Ho, C. & Huang, L. 1982 Subharmonics and vortex merging in mixing layers. J. Fluid Mech. 119, 443473.CrossRefGoogle Scholar
Ho, C.-M. & Nosseir, N. S. 1981 Dynamics of an impinging jet. Part 1. The feedback phenomenon. J. Fluid Mech. 105, 119142.CrossRefGoogle Scholar
Hong, S., Speth, R. L., Shanbhogue, S. J. & Ghoniem, A. F. 2013 Examining flow-flame interaction and the characteristic stretch rate in vortex-driven combustion dynamics using piv and numerical simulation. Combust. Flame 160, 13811397.CrossRefGoogle Scholar
Huang, R. F. & Chang, K. T. 2004 Oscillation frequency in wake of a vee gutter. J. Propul. Power 20, 871878.CrossRefGoogle Scholar
Huerre, P. & Monkewitz, P. A. 1985 Absolute and convective instabilities in free shear layers. J. Fluid Mech. 159, 151168.CrossRefGoogle Scholar
Huerre, P. & Monkewitz, P. A. 1990 Local and global instabilities in spatially developing flows. Annu. Rev. Fluid Mech. 22, 473537.CrossRefGoogle Scholar
Jackson, C. P. 1987 A finite-element study of the onset of vortex shedding in flow past variously shaped bodies. J. Fluid Mech. 182, 2345.CrossRefGoogle Scholar
Juniper, M. P., Tammisola, O. L. & Lundell, F. 2011 The local and global stability of confined planar wakes at intermediate reynolds number. J. Fluid Mech. 686, 217238.CrossRefGoogle Scholar
Konstantinidis, E. & Balabani, S. 2007 Symmetric vortex shedding in the near wake of a circular cylinder due to streamwise perturbations. J. Fluids Struct. 23, 10471063.CrossRefGoogle Scholar
Lee, J. G. & Santavicca, D. A. 2003 Experimental diagnostics for the study of combustion instabilities in lean premixed combustors. J. Propul. Power 19, 735750.CrossRefGoogle Scholar
Leontini, J. S., Jacono, D. L. & Thompson, M. C. 2013 Wake states and frequency selection of a streamwise oscillating cylinder. J. Fluid Mech. 730, 162192.CrossRefGoogle Scholar
Lieuwen, T. C. 2012 Unsteady Combustor Physics. Cambridge University Press.CrossRefGoogle Scholar
Lieuwen, T., Rajaram, R., Neumeier, Y. & Nair, S. 2002 Measurements of incoherent acoustic wave scattering from turbulent premixed flames. Proc. Combust. Inst. 29, 18091815.CrossRefGoogle Scholar
Lieuwen, T. C. & Yang, V. 2005 Combustion Instabilities in Gas Turbine Engines: Operational Experience, Fundamental Mechanisms, and Modeling. AIAA.Google Scholar
Masselin, M. & Ho, C.-M. 1985 Lock-on and instability in a flat plate wake. In AIAA Shear Flow Control Conference.Google Scholar
Mei, R. 1996 Velocity fidelity of flow tracer particles. Exp. Fluids 22, 113.CrossRefGoogle Scholar
Meliga, P., Pujals, G. & Serre, E. 2012 Sensitivity of 2-d turbulent flow past a d-shaped cylinder using global stability. Phys. Fluids 24, 061701.CrossRefGoogle Scholar
Melling, A. 1997 Tracer particles and seeding for particle image velocimetry. Meas. Sci. Technol. 8, 14061416.CrossRefGoogle Scholar
Mettot, C., Sipp, D. & Bezard, H. 2014 Quasi-laminar stability and sensitivity analyses for turbulent flows: prediction of low-frequency unsteadiness and passive control. Phys. Fluids 26, 045112.CrossRefGoogle Scholar
Naudascher, E. & Rockwell, D. 1994 Flow-Induced Vibrations, an Engineering Guide. A.A. Balkema.Google Scholar
Nikias, C. L. & Petropulu, A. P. 1993 Higher-Order Spectra Analysis: A Nonlinear Signal Processing Framework. PTR Prentice-Hall.Google Scholar
Nogueria, J., Lecuona, A. & Rodriguez, P. A. 1997 Data validation, false vectors correction and derived magnitudes calculation on piv data. Meas. Sci. Technol. 8, 14931501.CrossRefGoogle Scholar
Otsu, N. 1975 A threshold selection method from gray-level histograms. Automatica 11, 2327.Google Scholar
Perry, A. E., Chong, S. M. & Lim, T. T. 1982 The vortex shedding process behind two-dimensional bluff bodies. J. Fluid Mech. 116, 7790.CrossRefGoogle Scholar
Poinsot, T. J., Trouve, A. C., Veynante, D. P., Candel, S. M. & Esposito, E. J. 1987 Vortex-driven acoustically coupled combustion instabilities. J. Fluid Mech. 177, 12651272.CrossRefGoogle Scholar
Prasad, A. & Williamson, C. H. K. 1997 The instability of the shear layer separating from a bluff body. J. Fluid Mech. 333, 375402.CrossRefGoogle Scholar
Provansal, M., Mathis, C. & Boyer, L. 1987 Bénard–von Kármán instability: transient and forced regimes. J. Fluid Mech. 182, 122.CrossRefGoogle Scholar
Roshko, A. 1955 On the wake and drag of bluff bodies. J. Aero. Sci. 22, 124132.CrossRefGoogle Scholar
Roshko, A. 1976 Structure of turbulent shear flows: a new look. AIAA J. 14, 13491357.CrossRefGoogle Scholar
Schadow, K. C. & Gutmark, E. 1992 Combustion instability related to vortex shedding in dump combustors and their passive control. Prog. Energy Combust. Sci. 18, 117132.CrossRefGoogle Scholar
Schmid, P. J. & Henningson, D. S. 2001 Stability and Transition in Shear Flows. Springer.CrossRefGoogle Scholar
Schuller, T., Ducruix, S., Durox, D. & Candel, S. 2002 Modeling tools for the prediction of premixed flame transfer functions. Proc. Combust. Inst. 29, 107113.CrossRefGoogle Scholar
Schumm, M., Berger, E. & Monkewitz, P. 1994 Self-excited oscillations in the wake of two-dimensional bluff bodies and their control. J. Fluid Mech. 271, 1753.CrossRefGoogle Scholar
Shanbhogue, S.2008 Dynamics of perturbed exothermic bluff-body flow-fields. PhD thesis, Atlanta, GA.Google Scholar
Shanbhogue, S. J., Husain, S. & Lieuwen, T. 2009a Lean blowoff of bluff body stabilized flames. Prog. Energy Combust. Sci. 35, 98120.CrossRefGoogle Scholar
Shanbhogue, S. J., Shin, D.-H., Hemchandra, S., Plaks, D. & Lieuwen, T. 2009b Flame-sheet dynamics of bluff-body stabilized flames during longitudinal acoustic forcing. Proc. Combust. Inst. 32, 17871794.CrossRefGoogle Scholar
Smith, D. A. & Zukoski, E. E. 1985 Combustion instability sustained by unsteady vortex combustion. In AIAA/SAE/ASEM/ASEE Joint Propulsion Conference.Google Scholar
Soria, J. 1996 An investigation of the near wake of a circular cylinder using a video-based digital cross-correlation particle image velocimetry technique. Exp. Therm. Fluid Sci. 12, 221233.CrossRefGoogle Scholar
Soteriou, M. C. & Ghoniem, A. F. 1994 The vorticity dynamics of an exothermic, spatially developing, forced reacting shear layer. Proc. Combust. Inst. 25, 12651272.CrossRefGoogle Scholar
Stansby, P. K. 1976 The locking-on of vortex shedding due to the cross-stream vibration of circular cylinders in uniform and shear flows. J. Fluid Mech. 74, 641665.CrossRefGoogle Scholar
Swami, A., Mendel, J. M. & Nikias, C. L.1993 Higher-Order Spectral Analysis Toolbox For Use with MATLAB.Google Scholar
Tanida, Y., Okajima, A. & Watanabe, Y. 1973 Stability of a circular cylinder oscillating in uniform flow or in a wake. J. Fluid Mech. 61, 769784.CrossRefGoogle Scholar
Willert, C. E. 1991 Digital particle image velocimetry. Exp. Fluids 10, 181193.CrossRefGoogle Scholar
Yang, V. & Culick, F. E. C. 1986 Analysis of low frequency combustion instabilities in a laboratory ramjet combustor. Combust. Sci. Technol. 45, 125.CrossRefGoogle Scholar
Yu, K., Trouve, A. & Candel, S. 1991 Combustion enhancement of a premixed flame by acoustic forcing with emphasis on role of large-scale vortical structures. In 29th Aerospace Sciences Meeting.Google Scholar
Yu, M.-H. & Monkewitz, P. A. 1990 The effect of nonuniform density on the absolute instability of two-dimensional inertial jets and wakes. Phys. Fluids 2, 11751181.CrossRefGoogle Scholar