Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-27T13:59:56.105Z Has data issue: false hasContentIssue false

Gas jets in an arbitrary stream

Published online by Cambridge University Press:  04 July 2016

R. M. C. So
Affiliation:
Mechanical and Aerospace Engineering, Arizona State University, Tempe, USA
H. Aksoy
Affiliation:
Mechanical and Aerospace Engineering, Arizona State University, Tempe, USA

Abstract

Self-preserving turbulent flows in the farfield of binary gas jets in an arbitrary stream are investigated. The governing equations solved are valid for jet flows only and are not applicable to wake flows where a linearised set of boundary layer equations are more appropriate. Gaussian error-functions are assumed for the mean excess velocity and mass fraction distributions. Thus formulated, the eddy diffusivities for momentum and mass are evaluated by solving the governing equations and are shown to vary across and along the jet. A condition is imposed on the eddy momentum diffusivity so that it correctly approaches the limiting behaviour for the case of an incompressible free round jet. This condition gives rise to an auxiliary equation for the determination of the decay of centreline properties and jet growth. The new and more general auxiliary equation is shown to model fluid entrainment and to reduce correctly to previous equations derived for the special cases of free gas jets and incompressible heated jets in a co-flowing stream. Thus deduced, the new auxiliary equation is solved together with other conservation equations to yield a set of growth rate and decay laws. The derived growth rate and decay laws correctly approach the various laws derived earlier for different special cases and correlate well with experimental measurements reported in the literature. The present solutions also represent solutions for compressible jets in a general stream where the pressure field is constant. Finally, this approach of analysing the self-preserving mean jet flow is also applicable to the study of wake flows where the linearised boundary-layer equations are solved.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1993 

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

1. Launder, B.E., Morse, A.P., Rodi, W. and Spalding, D.B. Prediction of free shear flows — a comparison of the performance of six turbulence models, NASA SP-321, 1972, pp 361-426.Google Scholar
2. Launder, B.E. and Morse, A.P. Numerical prediction of axisymmetric free shear flows with a Reynolds stress closure, Turbulent Shear Flows I, Durst, F., Launder, B.E., Schmidt, F.W. and Whitelaw, J.H. (Eds) published by Springer-Verlag, 1979, pp 279294.Google Scholar
3. Pope, S.B. An explanation of the turbulent round-jet/plane-jet anomaly, AIAA J, 1978, 16, pp 279281.Google Scholar
4. Cho, J.R. and Chung, M.K. A proposal of k-ε-γ equation turbulence model, J Fluid Mech, 1992, 237, pp 301322.Google Scholar
5. Libby, P.A. Theoretical analysis of turbulent mixing of reactive gases with application to supersonic combustion of hydrogen, Am Rocket Soc J, 1962, 32, pp 388396.Google Scholar
6. Maczynski, J.F.J. A round jet in an ambient co-axial stream, J Fluid Mech, 1962, 13, pp 597610.Google Scholar
7. Patel, R.P. Turbulent jets and wall jets in uniform streaming flow, Aeronaut Q, 1971, 22, pp 311326.Google Scholar
8. Antonia, R.A. and Bilger, R.W. The prediction of the axisymmetric turbulent jet issuing into a co-flowing stream, Aeronaut Q, 1974, 25, pp 6980.Google Scholar
9. Antonia, R.A. and Bilger, R.W. The heated round jet in a co-flowing stream, A1AA J, 1976, 14, pp 15411547.Google Scholar
10. Morton, B.R., Taylor, G.I. and Turner, J.S. Turbulent gravitational convection from maintained and instantaneous sources, Proc Roy Soc A, 1956, 234, pp 122.Google Scholar
11. So, R.M.C. and Hwang, B.C. On similarity solutions for turbulent and heated round jets, Z angew Math Phys, 1986, 37, pp 624631.Google Scholar
12. So, R.M.C. and Liu, T.M. On self-preserving, variable-density, turbulent free jets, Z angew Math Phys, 1986, 37, pp 538558.Google Scholar
13. So, R.M.C. and Hwang, B.C. On incompressible, turbulent, heated round jets in a co-flowing stream, Aeronaut J, 1989, 93, pp 100110.Google Scholar
14. Bradbury, L.J.S. and Riley, J. The spread of a turbulent plane jet issuing into a parallel moving stream, J Fluid Mech, 1967, 27, pp 381397.Google Scholar
15. Smith, D.J. and Hughes, T. Some measurements in a turbulent circular jet in the presence of a co-flowing free-stream, Aeronaut Q, 1977, 28, pp 185196.Google Scholar
16. Antonia, R.A. and Bilger, R.W. An experimental investigation of an axisymmetric jet in a co-flowing air stream, J Fluid Mech, 1973, 61, pp 805822.Google Scholar
17. Biringen, S. An experimental investigation of a turbulent round jet in a coflowing airstream, ASME Paper 86-WA/FE-13, 1986.Google Scholar
18. Forstall, W. and Shapiro, A.H. Momentum and mass transfer in coaxial gas jets, J Appl Mech, 1950, 17, pp 399408.Google Scholar
19. Zakkay, V. Krause, E. and Woo, S.D.L. Turbulent transport properties for axisymmetric heterogeneous mixing, AIAA J, 1964, 2, pp 19391947.Google Scholar
20. Alpinieri, L.J. Turbulent mixing of coaxial jets, AIAA J, 1964, 2, pp 15601567.Google Scholar
21. Abramovich, G.N., Yakovlevsky, O.V., Smirnova, L.P., Secundov, A.N. and Krasheninnikov, S.Yu. An investigation of the turbulent jets of different gases in a general stream, Astronaut Acta, 1969, 14, pp 229240.Google Scholar
22. Enotiadis, A.C., Gladnick, P.G., Samuelsen, G.S. and LaRue, J.C. Statistical and spectral properties of a Freon jet in a co-flowing stream, Joint Conference of the Western Section, Combustion Institute, 1986.Google Scholar
23. So, R.M.C., Zhu, J.Y., Otugen, M.V. and Hwang, B.C. Some measurements in a binary gas jet, Exp Fluids, 1990, 9, pp 273284.Google Scholar
24. Dowling, D.R. and Dimotakis, P.E. Similarity of the concentration field of gas-phase turbulent jets, J Fluid Mech, 1990, 218, pp 109141.Google Scholar
25. So, R.M.C. and Aksoy, H. On vertical turbulent buoyant jets, Int J Heat Mass Trans, 1993, 36, pp 31873200.Google Scholar