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Парадоксы гидродинамики реверсивных течений в приливных устьях рекстатья
- Авторы: Алабян А.М., Панченко Е.Д., Медин А.М.
- Сборник: Труды III Всероссийской конференции «Гидрометеорология и экология: достижения и перспективы развития»
- Год издания: 2019
- Место издания: Химиздат Санкт-Петербург
- Первая страница: 61
- Последняя страница: 64
- Аннотация: Hydrometric measurements in the tidal estuaries of the White Sea (Kyanda, Tamitsa, Syomzha) using modern hydrometric and geodetic equipment allowed to obtain new and very exciting results regarding the characteristics of reversible water flows under various combinations of the tide height and river runoff. In particular, during continuous observations during the tidal cycle, significant variations in hydraulic resistance coefficients, as well as Coriolis and Boussinesq velocity corrections, were revealed. These parameters are included in the Saint-Venant equations, which currently represent the fundamental basis for calculating the unsteady flow in natural channels. The significant variability of Coriolis and Boussinesq coefficients during the tidal cycle raises the question of the need to modify the Saint-Venant equations by introducing additional terms in them to reflect this variability. Cyclic variations in hydraulic resistance in a wide range of values have been observed in all the tidal estuaries studied. Throughout some phases of the flood-ebb transition a unique hydrodynamic phenomenon of the negative hydraulic resistance was observed. This phenomenon can be interpreted under the assumption that the negative eddy viscosity manifests itself in reversible water flows, when the energy of turbulent vortex formations is transferred to the translational motion of the water flow (“counter-dissipation” of the averaged flow energy). This phenomenon was previously predicted theoretically, but experimentally has been investigated for the first time.
- Добавил в систему: Алабян Андрей Михайлович