Abstract—
The problem of generation of internal gravity waves by a local harmonic disturbance source in a stratified medium with two-dimensional linear shear flows is considered. Integral representations of the solutions are obtained under the assumption of constant buoyancy frequency in satisfying the Miles–Howard stability condition. The properties of the spectral problem are investigated for small wavenumbers. The results of numerical calculations of the dispersion curves and phase patterns of the excited wave fields are given for various linear distributions of shear flows. It is shown that taking the two-dimensional character of shear flows into account is the cause of appreciable asymmetry of both the dispersion curves and the isophase lines. Transformation of the phase patterns of the fields of internal gravity waves is studied numerically as a function of the generation parameters.
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The work is carried out in accordance with the themes of the State tasks nos. AAAA-A20-120011690131-7 (Bulatov) and FMWE-2021-0002 (Vladimirov) and with a partial financial support from the Russian Foundation for Basic Research (project no. 20-01-00111A).
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Translated by E.A. Pushkar
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Bulatov, V.V., Vladimirov, I.Y. Internal Gravity Waves Generated by an Oscillating Disturbance Source in a Stratified Medium in the Presence of Two-Dimensional Shear Flows. Fluid Dyn 57, 477–485 (2022). https://doi.org/10.1134/S0015462822040012
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DOI: https://doi.org/10.1134/S0015462822040012