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Effects of heat release in a turbulent, reacting shear layer

  • J. C. Hermanson (a1) and P. E. Dimotakis (a1)

Abstract

Experiments were conducted to study the effects of heat release in a planar, gas-phase, reacting mixing layer formed between two free streams, one containing hydrogen in an inert diluent, the other, fluorine in an inert diluent. Sufficiently high concentrations of reactants were utilized to produce adiabatic flame temperature rises of up to 940 K (corresponding to 1240 K absolute). The temperature field was measured at eight fixed points across the layer. Flow visualization was accomplished by schlieren spark and motion picture photography. Mean velocity information was extracted from Pitot-probe dynamic pressure measurements. The results showed that the growth rate of the layer, for conditions of zero streamwise pressure gradient, decreased slightly with increasing heat release. The overall entrainment into the layer was substantially reduced as a consequence of heat release. A posteriori calculations suggest that the decrease in layer growth rate is consistent with a corresponding reduction in turbulent shear stress. Large-scale coherent structures were observed at all levels of heat release in this investigation. The mean structure spacing decreased with increasing temperature. This decrease was more than the corresponding decrease in shear-layer growth rate, and suggests that the mechanisms of vortex amalgamation are, in some manner, inhibited by heat release. The mean temperature rise profiles, normalized by the adiabatic flame temperature rise, were not greatly changed in shape over the range of heat release of this investigation. A small decrease in normalized mean temperature rise with heat release was however observed. Imposition of a favourable pressure gradient in a mixing layer with heat release resulted in an additional decrease in layer growth rate, and caused only a very slight increase in the mixing and amount of chemical product formation. The additional decrease in layer growth rate is shown to be accounted for in terms of the change in free-stream velocity ratio induced by the pressure gradient.

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Batt, R. G.: 1975 Some measurements on the effect of tripping the two-dimensional shear layer. AIAA J. 13, 245247.
Baulch, D. L., Duxbury, J., Grant, S. J. & Montague, D. C., 1981 Evaluated kinetic data for high temperature reactions, vol. 4. J. Phys. Chem. Ref. Data, 10, Suppl. 1.
Bernal, L. P.: 1981 The coherent structure of turbulent mixing layers: I. Similarity of the primary vortex structure. II. Secondary streamwise vortex structure. Ph.D. thesis, California Institute of Technology.
Bernal, L. P., Breidenthal, R. E., Brown, G. L., Konrad, J. H. & Roshko, A., 1979 On the development of three-dimensional small scales in turbulent mixing layers. In Turbulent Shear Flows 2, Seond Intl Symp. on Turbulent Shear Flows, July 1979, p. 305. Springer.
Bradshaw, P.: 1966 The effect of initial conditions of the development of a free shear layer. J. Fluid Mech. 26, 225236.
Bray, K. N. C. & Libby, P. A. 1981 Countergradient diffusion in pre-mixed turbulent flames, AIAA J. 19, 205213.
Breidenthal, R. E.: 1981 Structure in turbulent mixing layers and wakes using a chemical reaction. J. Fluid Mech. 109, 124.
Broadwell, J. E. & Breidenthal, R. E., 1982 A simple model of mixing and chemical reaction in a turbulent shear layer. J. Fluid Mech. 125, 397410.
Browand, F. K. & Latigo, B. O., 1979 Growth of the two-dimensional mixing layer from a turbulent and non-turbulent boundary layer. Phys. Fluids 22, 10111019.
Browand, F. K. & Troutt, T. R., 1985 The turbulent mixing layer: geometry of large vortices. J. Fluid Mech. 158, 489509.
Brown, G. L. & Roshko, A., 1971 The effect of density differences on the turbulent mixing layer. In Turbulent Shear Flows: AGARD-CP-93, 23.123.12.
Brown, G. L. & Roshko, A., 1974 On density effects and large structure in turbulent mixing layers. J. Fluid Mech. 64, 775816.
Brown, J. L.: 1978 Heterogeneous turbulent mixing layer investigations utilizing a 2-D 2-color laser Doppler anemometer and using a concentration probe. Ph.D. dissertation, University of Missouri at Columbia.
Caldwell, F. R.: 1962 Thermocouple materials. National Bureau of Standards Monograph 40. United States Department of Commerce, National Bureau of Standards.
Cohen, N. & Bott, J. F., 1982 Review of rate data for reactions of interest in HF and DF lasers. The Aerospace Corporation Rep. SD-TR-82-86.
Dimotakis, P. E.: 1986 Entrainment and growth of a fully developed, two-dimensional shear layer. AIAA J. 24, 17911796.
Dimotakis, P. E.: 1987 Turbulent shear layer mixing with fast chemical reactions. United States-France Joint Workshop on Turbulent Reacting Flows, Rouen, France, July 1987 (submitted to J. Fluid Mech).
Dimotakis, P. E. & Brown, G. L., 1976 The mixing layer at high Reynolds number: large-structure dynamics and entrainment. J. Fluid Mech. 78, 535560.
Effelsberg, E. & Peters, N., 1983 A composite model for the conserved scalar PDF. Combust. Flame 50, 351360.
Ganji, A. T. & Sawyer, R. F., 1980 Experimental study of the flowfield of a two-dimensional, premixed turbulent flame. AIAA J. 18, 817824.
Hermanson, J. C.: 1985 Heat release effects in a turbulent, reacting shear layer. Ph.D. thesis, California Institute of Technology.
Hermanson, J. C., Mungal, M. G. & Dimotakis, P. E., 1987 Heat release effects on shear layer growth and entrainment. AIAA J. 25, 578583.
Kee, R. J., Miller, J. A. & Jefferson, T. H., 1980 CHEMKIN: A general purpose, problem independent, transportable, Fortran chemical kinetics code package. SANDIA Rep. SAND80-8003.
Keller, J. O. & Daily, J. W., 1983 The effect of large heat release on a two-dimensional mixing layer. AIAA Paper 83-0487 21st Aerospace Sciences Meeting, January 1983.
Kollman, W. & Janicka, J., 1982 The probability density function of a passive scalar in turbulent shear flows. Phys. Fluids 25, 17551769.
Konrad, J. H.: 1976 An experimental investigation of mixing in two-dimensional turbulent shear flows with applications to diffusion-limited chemical reactions. Ph.D. dissertation, California Institute of Technology.
Koochesfahani, M. M., Catherasoo, C. J., Dimotakis, P. E., Gharib, M. & Lang, D. B., 1979 Two-point LDV measurements in a plane mixing layer. AIAA J. 17, 13471351.
Koochesfahani, M. M. & Dimotakis, P. E., 1986 Mixing and chemical reactions in a turbulent liquid mixing layer. J. Fluid Mech. 170, 83112.
Koop, C. G. & Browand, F. K., 1979 Instability and turbulence in a stratified fluid with shear. J. Fluid Mech. 93, 135159.
Lang, D. B.: 1985 Laser Doppler velocity and vorticity measurements in turbulent shear layers. Ph.D. thesis, California Institute of Technology.
Marble, F. E. & Broadwell, J. E., 1977 The coherent flame model for turbulent chemical reactions. Project SQUID Tech. Rep. TRW-9-PU.
Masutani, S. M. & Bowman, C. T., 1986 The structure of a chemically reacting plane mixing layer. J. Fluid Mech. 172, 93126.
McMurtry, P. A., Jou, W.-H., Riley, J. J. & Metcalfe, R. W., 1986 Direct numerical simulations of a reacting mixing layer with chemical heat release. AIAA J. 24, 962970.
McMurtry, P. A. & Riley, J. J., 1987 Mechanisms by which heat release affects the flow field in a chemically reacting, turbulent mixing layer. AIAA Paper 87-0131, 25th Aerospace Sciences Meeting, January 1987.
Mungal, M. G. & Dimotakis, P. E., 1984 Mixing and combustion with low heat release in a turbulent shear layer. J. Fluid Mech. 148, 349382.
Mungal, M. G., Hermanson, J. C. & Dimotakis, P. E., 1985 Reynolds number effects on mixing and combustion in a reacting shear layer. AIAA J. 23, 14181423.
Mungal, M. G. & Frieler, C. E., 1985 The effects of Damköhler number on a turbulent shear layer - experimental results. GALCIT Rep. FM85-01.
Paranthoen, P., Lecordier, J. D. & Petit, C., 1982 Influence of dust contamination on frequency response of wire resistance thermometers. DISA Information 27, 3637.
Pitz, R. W. & Daily, J. W., 1983 Combustion in a turbulent mixing layer formed at a rearward-facing step. AIAA J. 21, 15651570.
Pope, S. B.: 1981 A Monte Carlo method for the PDF equations of turbulent reactive flow. Combust. Sci. Tech. 25, 159174.
Prandtl, L.: 1925 Bericht über Untersuchungen zur ausgebildeten Turbulenz, Zr. angew. Math. Mech. 5, 136139.
Rajagopalan, S. & Antonia, R. A., 1981 Properties of the large structure in a slightly heated turbulent mixing layer of a plane jet. J. Fluid Mech. 105, 261281.
Rebollo, M. R.: 1973 Analytical and experimental investigation of a turbulent mixing layer of different gases in a pressure gradient. Ph.D. thesis, California Institute of Technology.
Scadron, M. D. & Warshawsky, I., 1952 Experimental determination of time constants and Nusselt numbers for bare-wire thermocouples in high-velocity air streams and analytic approximation of conduction and radiation errors. NACA Tech Note 2599.
Spalding, D. B.: 1986 The two-fluid model of turbulence applied to combustion phenomena. AIAA J. 24, 876884.
Spencer, B. W. & Jones, B. G., 1971 Statistical investigation of pressure and velocity fields in the turbulent two stream mixing layer. AIAA Paper 71-613, 11th Aerospace Sciences Meeting, January 1971.
Stårner, S. H. & Bilger, R. W. 1980 LDA measurements in a turbulent diffusion flame with axial pressure gradient. Combust. Sci. Tech. 21, 259276.
Wallace, A. K.: 1981 Experimental investigation of the effects of chemical heat release in the reacting turbulent plane shear layer. Ph.D. thesis, The University of Adelaide; also AFOSR Rep. TR-84-0650.
Winant, C. D. & Browand, F. K., 1974 Vortex pairing: the mechanism of turbulent mixing-layer growth at moderate'Reynolds number. J. Fluid Mech. 63, 237255.
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Effects of heat release in a turbulent, reacting shear layer

  • J. C. Hermanson (a1) and P. E. Dimotakis (a1)

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