Hydraulic Flow through a Contraction: Multiple Steady States
نویسندگان
چکیده
We consider shallow water flows through a channel with a contraction by experimental and theoretical means. The horizontal channel consists of a sluice gate and an upstream channel of constant width b0 ending in a linear contraction of minimum width bc. Experimentally, we observe upstream steady and moving bores/shocks, and oblique waves in the contraction, as single and multiple steady states, as well as a steady reservoir with a two-dimensional hydraulic jump in the contraction occurring in a small section of the bc/b0 and Froude number parameter plane. Inviscid one-dimensional hydraulic theory provides a comprehensive leading-order explanation, but quadratic friction is required to achieve quantitative agreement and stability.
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Hydraulic Flow through a Channel Contraction: Multiple Steady States
Fig. 3. Plus signs: smooth flows (ii); squares: upstream moving shocks (iii); diamonds: steady shocks (iii); circles: oblique waves (i). Solid stars: flows with three possible states for different configurations and paddle lengths. Indicative error bars. • Three multiple steady states in regions (i/iii/iv): Fig. 4. Multiple states: F0 = 3.07 & Bc = 0.7. Left to right: upstream steady shock (iii...
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