Hostname: page-component-8448b6f56d-jr42d Total loading time: 0 Render date: 2024-04-18T06:23:41.142Z Has data issue: false hasContentIssue false
  • English
  • Français

Mixing and combustion with low heat release in a turbulent shear layer

Published online by Cambridge University Press:  20 April 2006

M. G. Mungal  and
P. E. Dimotakis
M. G. Mungal
Affiliation:
Graduate Aeronautical Laboratories, California Institute of Technology, Pasadena, CA 91125
P. E. Dimotakis
Affiliation:
Graduate Aeronautical Laboratories, California Institute of Technology, Pasadena, CA 91125
Get access Rights & Permissions [Opens in a new window]

Abstract

Turbulent mixing and combustion are investigated in a gaseous shear layer formed between two streams: one containing a low concentration of hydrogen in nitrogen and the other containing a low concentration of fluorine in nitrogen. The resulting temperature field is measured simultaneously at eight points across the width of the layer using fast-response cold-wire thermometry. The results show the presence of large, hot structures separated by tongues of cool fluid that enter the layer from either side. The usual bell-shaped mean-temperature profiles therefore result from a duty cycle whereby a fixed probe sees alternating hot and cool fluid, which results in the local mean. The adiabatic flame temperature is not achieved in the mean, at any location across the layer. For fixed velocities, it is found that, in general, two different mean-temperature profiles result from a given pair of reactant compositions if the sides of the layer on which they are carried are exchanged (‘flipped’). This finding is a direct consequence of the asymmetric entrainment of fluid into the layer. Results are compared with the predictions of Konrad and discussed in the context of the Broadwell–Breidenthal model. By comparison with the liquid result of Breidenthal, the amount of product formed in the layer at high Reynolds number is found to be dependent upon the Schmidt number. Results for a helium–nitrogen layer are discussed briefly.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 148 , November 1984 , pp. 349 - 382
Copyright
© 1984 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

Batt, R. G. 1977 Turbulent mixing of passive and chemically reacting species in a low-speed shear layer. J. Fluid Mech. 82, 53–95.Google Scholar
Baulch, D. L., Drysdale, D. D. & Horne, D. G. 1973 Evaluated Kinetic Data for High Temperature Reactions, vol. 2. CRC Press.
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.Google Scholar
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, Caltech.
Betchov, R. 1948 Proc. Ned. Akad. Wetenshappen 51, 721.
Breidenthal, R. E. 1978 A chemically reacting turbulent shear layer. Ph.D. thesis, Caltech.
Breidenthal, R. E. 1981 Structure in turbulent mixing layers and wakes using a chemical reaction. J. Fluid Mech. 109, 1–24.Google Scholar
Broadwell, J. E. 1982 A model of turbulent diffusion flames and nitric oxide generation part I. TRW Document 38515-6001-UT-00.Google Scholar
Broadwell, J. E. & Breidenthal, R. E. 1982 A simple model of mixing and chemical reaction in a turbulent shear layer. J. Fluid Mech. 125, 397–410.Google Scholar
Brown, G. L. 1974 The entrainment and large structure in turbulent mixing layers. In Proc. 5th Australasian Conf. on Hydraul. and Fluid Mech., pp. 352–359.
Brown, G. L. & Rebollo, M. R. 1972 A small, fast response probe to measure composition of a binary gas mixture. AIAA J. 10, 649–652.Google Scholar
Brown, G. L. & Roshko, A. 1971 The effect of density difference on the turbulent mixing layer. Turbulent Shear Flows; AGARD-CP-93, 23-1.Google Scholar
Brown, G. L. & Roshko, A. 1974 On density effects and large structure in turbulent mixing layers. J. Fluid Mech. 64, 775–816.Google Scholar
Brown, J. L. 1978 Heterogeneous turbulent mixing layer investigations utilizing a 2-D 2-color laser Doppler anemometer and a concentration probe. Ph.D. thesis, University of Missouri—Columbia.
Burke, S. P. & Schumann, T. E. W. 1928 Diffusion flames. Indust. Engng Chem. 20, 998–1006.Google Scholar
Chen, H., Daugherty, J. D. & Fyfe, W. 1975 TA5–H2/F2. Flame propagation and repetitively pulsed hydrogen fluoride (HF) chain-reaction laser. IEEE J. Quantum Electronics QE-11, 8, 648–653.Google Scholar
Chmielewski, G. E. 1974 Boundary layer considerations in the design of aerodynamic contractions. J. Aircraft 11, 435–438.Google Scholar
Cohen, N. & Bott, J. F. 1982 Review of rate data for reactions of interest in HF and DF lasers. The Aerospace Corp. Rep. SD-TR-82-86.Google Scholar
Cool, T. A., Stephens, R. R. & Shirley, J. A. 1970 HCl, HF, and DF partially inverted cw chemical lasers. J. Appl. Phys. 41, 4038–4050.Google Scholar
Dimotakis, P. E. 1984 Entrainment into a fully developed two-dimensional shear layer. AIAA-84-0368.Google Scholar
Dimotakis, P. E. & Brown, G. L. 1976 The mixing layer at high Reynolds number: large structure dynamics and entrainment. J. Fluid Mech. 78, 535–560.Google Scholar
Driscoll, R. J. & Kennedy, L. A. 1982 A fluid element model for turbulent mixing and combustion. In Proc. 19th Intl Symp. on Combustion. The Combustion Institute.
Effelsberg, E. & Peters, N. 1983 A composite model for the conserved scalar PDF. Combust. Flame 50, 351–360.Google Scholar
Fiedler, H. F. 1974 Transport of heat across a plane turbulent mixing layer. Adv. Geophy. 18A, 93–109.Google Scholar
Fiedler, H. F. 1975 On turbulent structure and mixing mechanisms in free turbulent shear flows. In Turbulent Mixing in Nonreactive and Reactive Flows, A Project SQUID Workshop, pp. 381–410. Plenum.
Ganji, A. T. & Sawyer, R. F. 1980a Turbulence, combustion, pollutant, and stability characterization of a premixed, step combustor. NASA CR 3230.Google Scholar
Ganji, A. T. & Sawyer, R. F. 1980b Experimental study of the flowfield of a two-dimensional premixed turbulent flame. AIAA J. 18, 817–824.Google Scholar
Gmelin 1980 Handbook of Inorganic Chemistry: F Fluorine Suppl., Vol. 2: The Element, p. 108. Springer.
Ho, C.-M. & Huerre, P. 1984 Perturbed free shear layers. Ann. Rev. Fluid Mech. 16, 365–425.Google Scholar
Keller, J. O. & Daily, J. W. 1983 The effect of large heat release on a two dimensional mixing layer. AIAA-83-0472.Google Scholar
Kollmann, W. & Janicka, J. 1982 The probability density function of a passive scalar in turbulent shear flows. Phys. Fluids 25, 1755–1769.Google Scholar
Konrad, J. H. 1976 An experimental investigation of mixing in two-dimensional turbulent shear flows with application to diffusion-limited chemical reactions. Ph.D. Thesis, Caltech; and Project SQUID Tech. Rep. CIT-8-PU.
Koochesfahani, M. M. 1984 Experiments on turbulent mixing and chemical reactions in a liquid mixing layer. Ph.D. thesis, Caltech.
Koochesfahani, M. M. & Dimotakis, P. E. 1984 Laser induced fluorescence measurements of concentration in a plane mixing layer. AIAA-84-0198.Google Scholar
Koochesfahani, M. M., Dimotakis, P. E. & Broadwell, J. E. 1983 Chemically reacting turbulent shear layers. AIAA-83-0475.Google Scholar
Kristmanson, D. & Danckwerts, P. V. 1961 Studies in turbulent mixing—I. Dilution of a jet. Chem. Engng Sci. 6, 267–277.Google Scholar
Liñan, A. 1981 Lewis number effects on the structure and extinction of diffusion flames due to strain. In The Role of Coherent Structures in Modelling Turbulence and Mixing (ed. J. Jimenez). Lecture Notes in Physics, vol. 136, pp. 333–339. Springer.
Marble, F. E. & Broadwell, J. E. 1977 The coherent flame model for turbulent chemical reactions. Project SQUID Tech. Rep. TRW-9-PU.Google Scholar
Mungal, M. G. 1983 Experiments on mixing and combustion with low heat release in a turbulent shear flow. Ph.D. thesis, Caltech.
Mungal, M. G., Dimotakis, P. E. & Broadwell, J. E. 1984 Turbulent mixing and combustion in a reacting shear layer. AIAA J. 22, 797–800.Google Scholar
Mungal, M. G., Dimotakis, P. E. & Hermanson, J. C. 1984 Reynolds number effects on mixing and combustion in a reacting shear layer. AIAA-84-0371.Google Scholar
Paranthoen, P., Lecordier, J. C. & Petit, C. 1982a Influence of dust contamination of frequency response of wire resistance thermometers. DISA Info. 27, 36–37.Google Scholar
Paranthoen, P., Petit, C. & Lecordier, J. C. 1982b The effect of the thermal prong—wire interaction on the response of a cold wire in gaseous flows (air, argon and helium). J. Fluid Mech., 124, 457–473.Google Scholar
Pitz, R. W. & Daily, J. W. 1983 Combustion in a turbulent mixing layer formed at a rearward-facing step. AIAA J. 21, 1565–1570.Google Scholar
Pope, S. B. 1981 A Monte Carlo method for the PDF equations of turbulent reactive flow. Combust. Sci. Tech. 25, 159–174.Google Scholar
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, 261–281.Google Scholar
Rapp, D. & Johnston, H. S. 1960 Nitric oxide—fluorine dilute diffusion flame. J. Chem. Phys. 33, 695–699.Google Scholar
Scadron, M. D. & Warshawsky, I. 1952 Experimental determination ot time constants and Nusselt numbers for bare-wire thermocouples in high-velocity air streams and analytic approximation of conduction and radiation errors. NACA TN 2599.Google Scholar
Spalding, D. B. 1978 A general theory of turbulent combustion. J. Energy 2, 16–23.Google Scholar
Toor, H. L. 1962 Mass transfer in dilute turbulent and nonturbulent systems with rapid irreversible reactions and equal diffusivities. AIChE J. 8, 70–78.Google Scholar
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.
White, F. M. 1974 Viscous Fluid Flow, p. 315. McGraw-Hill.
Wilson, R. A. M. & Danckwerts, P. V. 1964 Studies in turbulent mixing—II. A hot-air jet. Chem. Engng Sci. 19, 885–895.Google Scholar
Winant, C. D. & Browand, F. R. 1974 Vortex pairing; the mechanism of turbulent mixing-layer growth at moderate Reynolds number. J. Fluid Mech. 63, 417–432.Google Scholar
Witte, A. B., Broadwell, J. E., Shackleford, W. L., Cummings, J. C., Trost, J. E., Whitman, A. S., Marble, F. E., Crawford, D. R., Jacobs, T. A. 1974 Aerodynamic reactive flow studies of the H2F2 laser—II. Air Forces Weapons Lab., Kirtland Air Force Base, New Mexico, AFWL-TE-74-78, 33.