Turbulent unsteady flow profiles over an adverse slope

• Autorzy: Bose S.K. , Dey S.
• Języki publikacji: EN

Abstrakty

EN

When an unsteady free surface flow encounters an adverse slope, it results in a decelerating flow up th e adverse slope. The time dependent turbulent flow is treated here by appropriately reducing the two- dimensional Reynolds averaged Navier–Stokes equation along with the equation of continuity considering turbulence closure. With suitable choice of parameters, the resulting differential equations are numerically solved to compute free surface and st reamwise velocity profiles with time. It is found that initially the advancing free surface is convex upwards for a short time, followed by a jump of the free surface with a negative streamwise velocity that is a backwater rolling breaker due to deceleration of flow. At later time, however, the velocity becomes posi- tive, that is, the breakers roll forward. This dual feature of motion, that is a surge followed by rolling breakers, is repeated for sometime before the jumps stop. The theoretical analysis presented here is motivated by tidal bores propagating upstream in an estuarine river.

Słowa kluczowe

EN

flow characteristics; flow profiles; free surface profile; hydraulics; turbulent flow; unsteady flow

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2013
• Tom: Vol. 61, no. 1
• Strony: 84--97
• Opis fizyczny: Bibliogr. 30 poz.

Twórcy

autor

Bose S.K.

autor

Dey S.

• Centre for Theoretical Studies, Indian Institute of Technology, Kharagpur, West Bengal, India,

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