Influence of the source pulsations on the structure and internal dynamics of the intrusion
https://doi.org/10.7868/S2073667319020047
Abstract
Translated by E.S. Kochetkova
A 2-dimensional numerical model of stratified fluid dynamics in the vertical plane was used to investigate the structure and internal dynamics of density stratified intrusive current. The intrusion was formed by the pulsed inflow of two identical volumes of water of intermediate density into the two-layer stratified environment with a given time interval. Inflowing volumes of water were marked by different passive tracers. Initial stratification was defined by the density difference between the layers of equal thickness and the thickness of the intermediate layer. A set of dimensionless parameters is proposed which define the initial and boundary conditions of the problem. Numerical experiments showed that the evolution of the intrusive current is significantly influenced by pulsations of the inflow, particularly in the case when the time interval between the pulses is short. Depending on the intrusion parameters both is possible the acceleration and slowdown of horizontal propagation of the second intrusion volume. Dynamics of inflow of the second inflow volume is different for flows with supercritical and subcritical initial Froude number. Calculations show that the pulse nature of the source modifies the flow to the greatest extent when a short time interval between pulses.
Supporting agencies: Investigations are supported by RFBR, grant No. 19-05-00717.
About the Author
I. A. Isachenko
Shirshov Institute of Oceanology of Russian Academy of Sciences
Russian Federation
Russian Federation
Moscow
References
1. Simpson J.E. Gravity currents: In the environment and the laboratory. Cambridge, Cambridge university press, 1997. 244 p.
2. Samolûbov B.I. Density flows and diffusion of admixtures. M., Izd. LKI, 2007. 352 p. (in Russian).
3. Johnson G.C., Lueck R.G., Sanford T.B. Stress on the Mediterranean outflow plume: Part II. Turbulent dissipation and shear measurements. Journal of Physical Oceanography. 1994, 24, 10, 2084–2092.
4. Baringer M.O. N., Price J.F. Mixing and spreading of the Mediterranean outflow. Journal of Physical Oceanography. 1997, 27, 8, 1654–1677.
5. Price J.F., Baringer M.O. N., Lueck R.G., Johnson G.C., Ambar I., Parrilla G., Cantos A., Kennely M.A., Sanford, T. B. Mediterranean outflow mixing and dynamics. Science. 1993, 259, 5099, 1277–1282.
6. Latif M.A., Özsoy E., Oguz T., Ünlüata Ü. Observations of the Mediterranean inflow into the Black Sea. Deep Sea Research Part A. Oceanographic Research Papers. 1991, 38, S711–S723.
7. Di Iorio D., Yüce H. Observations of Mediterranean flow into the Black Sea. Journal of Geophysical Research: Oceans. 1999, 104, C2, 3091–3108.
8. Jarosz E., Teague W.J., Book J.W., Beşiktepe S. On flow variability in the Bosphorus Strait. Journal of Geophysical Research: Oceans. 2011, 116, C8, 1–17.
9. Peters H., Johns W., Bower A.S., Fratantoni D.M. Mixing and entrainment in the Red Sea outflow plume. Part I: Plume structure. Journal of Physical Oceanography. 2005, 35, 5, 569–583.
10. Käse R.H., Girton J.B., Sanford T.B. Structure and variability of the Denmark Strait Overflow: Model and observations. Journal of Geophysical Research: Oceans. 2003, 108, C6, 1–15.
11. Girton J.B., Sanford T.B. Descent and modification of the overflow plume in the Denmark Strait. Journal of Physical Oceanography. 2003, 33, 7, 1351–1364.
12. Macrander A., Käse R.H., Send U., Valdimarsson H., Jónsson S. Spatial and temporal structure of the Denmark Strait Overflow revealed by acoustic observations. Ocean Dynamics. 2007, 57, 2, 75–89.
13. Sutherland B.R. Interfacial gravity currents. I. Mixing and entrainment. Physics of Fluids. 2002, 14, 7, 2244–2254.
14. Mehta A.P., Sutherland B.R., Kyba P.J. Interfacial gravity currents. II. Wave excitation. Physics of Fluids. 2002, 14, 10, 3558– 3569.
15. O’Callaghan J., Rickard G., Popinet S., Stevens C. Response of buoyant plumes to transient discharges investigated using an adaptive solver. Journal of Geophysical Research: Oceans. 2010, 115, C11025, 1–17.
16. O’Callaghan J.M., Stevens C.L. Transient river flow into a fjord and its control of plume energy partitioning. Journal of Geophysical Research: Oceans. 2015, 120, 5, 3444–3461.
17. Gricenko V.A., Ûrova A.A. On the main phases of the separation of the bottom gravitational flow from the bottom slope. Okeanologiya. 1999, 39, 2, 187–191 (in Russian).
18. Gritsenko V.A., Chubarenko I.P. On features of structure of bottom gravity current frontal zone. Oceanology. 2010, 50, 1, 28–35.
19. Gricenko V.A. Study of the dynamics and internal structure of bottom gravity currents. Avtoref. diss. na soisk. st. d.f.-m.n. Kaliningrad, 1998 (in Russian).
20. Barenblatt G.I. Dimension Analysis: Uch. pos. M., MFTI, 1987, 165 p. (in Russian).
21. Britter R.E., Simpson J.E. Experiments on the dynamics of a gravity current head. Journal of Fluid Mechanics. 1978, 88, 2, 223–240.
22. Faust K.M., Plate E.J. Experimental investigation of intrusive gravity currents entering stably stratified fluids. Journal of Hydraulic Research. 1984, 22, 5, 315–325.
23. Turner J.S. Buoyancy effects in fluids. Cambridge university press, 1979. 362 p.
24. Roache P.J. Computational fluid dynamics. Hermosa publishers, 1972. 446 p.
25. Eastwood J.W., Hockney R.W. Computer Simulation using particles. New York, McGraw-Hill, 1981.
26. Anuchin V.N., Gritsenko V.A., Gritsenko I.V. On the structure of the head part of an intrusion in a stably stratified fluid. Okeanologiya. 1990, 30, 2, 216–221 (in Russian).
Review
For citations:
Isachenko I.A. Influence of the source pulsations on the structure and internal dynamics of the intrusion. Fundamental and Applied Hydrophysics. 2019;12(2):27-33. https://doi.org/10.7868/S2073667319020047
Views:
96
Email this article 