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Institut für Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum für Luft- und Raumfahrt e.V. German Aerospace Center 1 D. Panara,

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Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 1 D. Panara, R. Dannecker, B.Noll Institut fr Verbrennungstechnik DLR Deutsches Zentrum fr Luft- und Raumfahrt e.V. Mitglied der Herrmann von Helmholtz-Gemeinschaft Deutscher Forschungszentren HGF Stuttgart FLUISTCOM Fluid Structure Interaction for Combustion Systems ( MRTN-CT-2003-504183) Boundary Layers Response to Pulsating Combustor Flow Fluistcom Internal Meeting CIMNE Barcellona, June 2005 Slide 2 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 2 Overview Pulsating and Oscillatory Flows Experimental Evidences Aerodynamic Boundary Layer Response Thermal Boundary Layer Response Numerical Simulations High Reynolds vs. Low Reynolds Turbulence Models Near wall turbulence modeling, strategy of investigation Slide 3 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 3 Pulsating Flow Pioneering Studies: Flat Plate J. Cousteix and R. Houdeville VKI Lecture Series 1983 Pulsating Flow Aerodynamic responseThermal responseModeling Slide 4 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 4 Displacement thickness The displacement surface looks like a wavy wall moving back and forth Pulsating Flow Aerodynamic responseThermal responseModeling Slide 5 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 5 Near Wall Aerodynamic Response in Pulsating Pipe Flows Oscillating Flow: Pulsating Flow: Source: C.R.Lodahl, et al.: J.Fluid Mech., Vol.373, 1998 Source: A.Scotti, U. Piomelli : Physics of Fluids,13(5), 2001 Pulsating Flow Aerodynamic response Thermal responseModeling Slide 6 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 6 Turbulent Flows, Characteristic Parameters Source: M.Gndogdu, M.Carpinlioglu : JSME int. Journal, 42(3), 1999 Oscillating Turbulent Flow: Pulsating Turbulent Flow: Quasi Steady Flow Intermediate Frequency Quasi-Laminar Source: C.R.Lodahl, et al.: J.Fluid Mech., Vol.373, 1998 Mean parameters little affected Discrepancy close to bursting frequency Effects in the Stoke-layers Phase shift of c up to 45 Mean parameters affected / c up to 4 Strong unsteady effects Re-laminarization can occur Pulsating Flow Aerodynamic response Thermal responseModeling Slide 7 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 7 Near Wall Thermal Response Oscillation Amplitude Unknown Air pipe Flow Wide Range of Re number Wide Range of frequency Source: M.A. Habib et al., 2004 Pulsating Flow Aerodynamic response Thermal response Modeling Slide 8 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 8 Near Wall Thermal Response Source: A.R. Barker et al., 2000 Low Amplitude Oscillations Found No Heat Transfer Increase Heated Pipe Flow Wide Range of Re number + Plays an Important Role Phase Shift up to 180 o Pulsating Flow Aerodynamic response Thermal response Modeling Slide 9 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 9 Near Wall Thermal Response High Amplitude Pulsating Flow Heated pipe Flow Re-Laminarization Effects Narrow Range of Re number Wide Range of frequency Source: Y. Ishino, 1996 Pulsating Flow Aerodynamic response Thermal response Modeling Slide 10 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 10 Near Wall Thermal Response Resonant Channel Heated pipe Flow Resonant Standing Wave Frequency range 20 to 1000Hz Low Amplitude Oscillations Source: E. P. Valueva, 2000 Pulsating Flow Aerodynamic response Thermal response Modeling Slide 11 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 11 Near Wall Thermal Response Pulsating Motor Tail Pipe Cooled pipe Flow Frequency Range 100 Hz High Amplitude Oscillations Temperature Inlet Fluctuations Flow Conditions Similar to Combustor Flow Proved Failure of the Reynolds Analogy Source: E. Dec et al., 1991 Pulsating Flow Aerodynamic response Thermal response Modeling Slide 12 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 12 Near Wall Thermal Response Lacking of experimental data for current dominated flow Contradictory results in both laminar and turbulent flow conditions about the effect of oscillations on mean flow quantities Measured a phase shift up to 180 for the wall heat transfer (source Barker, Ishino ) Measured Heat Transfer Increasing In low-amplitude resonant pulsating flows (source Valueva) In low-frequency wave dominated pulsating flows (source Ishino) In Temperature fluctuating pulsating Flows (100 Hz) (source Dec) The Reynolds analogy proved not to hold in some cases Pulsating Flow Aerodynamic response Thermal response Modeling Slide 13 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 13 Turbulence Modeling Algebraic eddy viscosity models Two equations high-Reynolds model + Wall functions Two equations low-Reynolds model Full Reynolds stress models Two equations low Reynolds model + Unsteady near-wall corrections Inaccurate: Important role of transport of turbulent quantities Inaccurate: Steady flow wall function not suited Inaccurate: Eddy viscosity isotropy assumption Inaccurate: Insufficient near wall treatment Source: Fan, Lakshminarayana and Barnett, AIAA J. Oct. 1993 Pulsating Flow Aerodynamic response Thermal response Modeling Slide 14 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 14 Turbulence Modeling Low vs High Reynolds Turbulence Models Pulsating Flow Aerodynamic response Thermal response Modeling Slide 15 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 15 Pressure-strain Molecular viscosity Non zero value of at the wall Low-Reynolds model coefficients Correction for non local isotropy Full Reynolds model Critical closure Pressure-Strain term (fluctuating pressure) Two-equation model Inaccurate formulation for pulsating flows Accurate formulations for curvature and rotation Turbulence Modeling Source: Fan, Lakshminarayana and Barnett, AIAA J. Oct. 1993 Pulsating Flow Aerodynamic response Thermal response Modeling Slide 16 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 16 source: Abe et al. 1995 Turbulence Modeling source: Rogers et al. 1989 source: Gibson and Launder 1976 source: Koehler, Patankar 1991 Pulsating Flow Aerodynamic response Thermal response Modeling Reynolds Analogy Hypothesis Slide 17 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 17 Conclusions An overview on experimental evidences on pulsating flow has been presented The necessity of a better understanding of the aero-thermal near-wall flow behavior has been in deep analyzed An extensive bibliography on test cases and proposed models for unsteady flows has been acquired The limitations of steady state wall functions have been issued (cold flow) Hot flow unsteady simulation with different turbulent modeling are in progress Slide 18 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 18 Questions ? Slide 19 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 19 Extras Slide 20 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 20 source: Abe et al. 1995 Turbulence Modeling source: Rogers et al. 1989 source: Gibson and Launder 1976 source: Koehler, Patankar 1991 Pulsating Flow Aerodynamic response Thermal response Modeling Slide 21 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 21 Slide 22 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 22 References: AERODYNAMICS General overview aerodynamics: Low amplitude Gundogdu and Carpinlioglu,JSME,vol42,n3,1999 Scotti and Piomelli,physics of fluid,vol13,n5,2001 Low and High amplitude Lodahl and Sumer and Fredsoe, J.Fluid Mech,vol373,1998 Test case also (pipe water) Koehler and Patankar and Ibele,NASA-CR187177 Test cases Cousteix and Houdeville (flat plate air) Tardu and Binder and Blackwelder (pipe water) Ideas for unsteady turbulence models: Fan and Lakshminarayana,AIAA,vol31,1993 Mankbadi and Liu, J.Fluid Mech,vol238,1992 Hanjalic and Stosic Rodi and Scheuerer,J.Fluids Eng.,vol108,1986 Slide 23 Institut fr Verbrennungstechnik - Institute of Combustion Technology Deutsches Zentrum fr Luft- und Raumfahrt e.V. German Aerospace Center 23 References: HEAT TRANSFER Low amplitude Valueva,High Temperature,vol37,n5,1999 Test case also ( oscillating, compressible incompressible) Ideas for unsteady turbulence mo

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