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Medzveliya Manana Levanovna -
Moscow State University of Civil Engineering (MGSU)
Candidate of Technical Sciences, Associate Professor, Department of Hydraulic Engineering, Moscow State University of Civil Engineering (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation;
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.
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Pipiya Valeriy Valerianovich -
Breesize Trading Limited
Candidate of Technical Sciences, Senior Project Engineer, Breesize Trading Limited, 42 Mosfil’movskaya St., Moscow, 119285, Russian Federation;
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The authors consider the influence of the Reynolds number on the discharge ratio of the broad-crested weir. The authors provide an overview of their experiment in thearticle. They provide the equation that takes account of each factor of influence, including H — pressure over the broad-crested weir, P — weir height above the bottom, v — liquid velocity, ρ — liquid density, μ — dynamic viscosity, g — superficial tension, σ — gravity acceleration, q — per-unit weir flow, B — width of the weir, L — length of the weir. Superficial tension and liquid density values have minor differences for different fluids.A broad-crested weir flow was organized in the rectangular tray (6,000×100×200). The flow had the following dimensions: weir length L = 40 mm, weir height P = 50 mm, weir width B = 100 mm. The findings of the experiment have proven that the increase in the Reynolds number causes the increase in the broad-crested weir flow discharge ratio (at the pre-set relative pressure) and it approaches the constant value at Re ≈ 2000.
DOI: 10.22227/1997-0935.2013.4.167-171
References
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Medzveliya Manana Levanovna -
Moscow State University of Civil Engineering (MGSU)
Candidate of Technical Sciences, Associate Professor, Department of Hydraulic Engineering, Moscow State University of Civil Engineering (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation;
This e-mail address is being protected from spambots. You need JavaScript enabled to view it
.
The author considers the influences of the forces of viscosity and superficial tension on the discharge ratio in a channel with side narrowing. In the article the equation is presented that takes into account the influence of all the factors: the pressure, the speed of the liquid, liquid density, dynamic viscosity, superficial tension, gravity acceleration, expense per unit of width, width of the course, width of narrowing. Superficial tension and liquid density for the used liquids changed a little.The narrowing in the rectangular tray was achieved by force of flowing liquid between rectangular parallelepipeds, which were attached to the wall of the tray. The dimensions of the rectangular parallelepipeds were: the length L = 200 mm, the width B = 33 mm, and the depth of the mouth b = 34 mm.The findings of the experiment proved that the increase in the Reynolds number causes the increase flow discharge ratio and it approaches the constant value at Re ? 4000.
DOI: 10.22227/1997-0935.2015.6.110-114
References
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- Al’tshul’ A.D. Istechenie iz otverstiy zhidkostey s povyshennoy vyazkost’yu [Outflows of Hyperviscosity Liquids through Holes]. Neftyanoe khozyaystvo [Crude Oil Economy]. 1950, no. 2, pp. 55—60. (In Russian)
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