Name: sluice gate water pressure and reaction force
Uploaded: 2025-02-13T15:43:22.000Z
Duration: 1 min 11 s
Channel: JoVE

Шлюзовой затвор — это вертикальный барьер, который контролирует поток воды в канале.
Чтобы рассчитать силы, действующие на шлюзовой затвор, рассмотрим воду, протекающую под затвором.
Силы зависят от глубины воды вверх и вниз по течению.
На стороне вверх по течению глубина составляет z1, а на стороне ниже по течению глубина составляет z2.
Разница в давлении между двумя сторонами создает результирующую силу на затворе.
Используя принцип Бернулли, скорость воды под затвором, V2, может быть рассчитана на основе разницы давлений и перепада высоты.
Сила реакции на затвор рассчитывается по гидростатической силе, действующей за счет водяного столба с обеих сторон.
Сила увеличивается при закрытии ворот из-за большей разницы давлений.
Когда затвор открывается, сила реакции уменьшается, так как вода свободно течет под затвором, уменьшая чистую разницу гидростатических давлений.
Этот принцип позволяет определить анкерную силу, необходимую для удержания ворот на месте во время работы.

Пример конструкции: силы в шлюзовом затворе

Design Example: Forces in Sluice Gate

В гидротехнике шлюзовые затворы необходимы для управления потоком воды через каналы, водохранилища и ирригационные системы. Шлюзовые затворы, действуя как вертикальные барьеры, регулируют воду, регулируя высоту открытия затвора, что изменяет скорость и давление воды, протекающей под затвором. Понимание задействованных сил имеет решающее значение для проектирования шлюзовых затворов, которые могут выдерживать динамические перепады давления, особенно когда затвор закрыт или частично открыт.

 Ключевые переменные при анализе сил шлюзовых затворов включают глубину восходящего потока z_1 и глубину нисходящего потока z_2. Когда затвор закрыт, глубина воды больше на стороне восходящего потока, что создает значительный перепад давления на затворе. Эта разница давления создает чистую силу, которая требует системы анкеровки для надежного удержания затвора на месте. Гидростатическое давление, оказываемое на сторону восходящего потока, пропорционально глубине воды и силе тяжести, в то время как давление нисходящего потока зависит от z_2. Результирующий градиент давления на затворе создает результирующую силу, направленную вниз по течению.

 Когда затвор шлюза частично открыт, вода течет под ним, и принцип Бернулли может быть использован для определения скорости потока ниже по течению, V_2.

<img alt="Equation 1" src="/files/ftp_upload/18056/18056_Equation_1.svg" style="text-align: center; height: 90px;">


 Учитывая глубины вверх и вниз по течению, принцип связывает изменение давления из-за разницы в высоте воды, что позволяет вычислить V_2 на основе разницы высот и градиентов давления. Этот поток уменьшает давление, оказываемое на затвор, допуская движение, а не накопление, уменьшая чистую силу, поскольку вода течет свободно.

 Суммарная сила реакции на затвор шлюза в основном определяется гидростатической силой столба воды выше по течению, которая достигает максимума, когда затвор полностью закрыт. По мере открытия шлюза и протекания воды под ним, уменьшение перепада давления снижает силу реакции.

<img alt="Equation 2" src="/files/ftp_upload/18056/18056_Equation_2.svg" style="text-align: center; height: 90px;">

Шлюзовой затвор — это вертикальный барьер, который контролирует поток воды в канале.
Чтобы рассчитать силы, действующие на шлюзовой затвор, рассмотрим воду, протекающую под ...

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JoVE Core

Civil Engineering

Unit 1

Раздел 1

Finite Control Volume Analysis

Анализ методом конечных контрольных объемов

KEY TERMS AND CONCEPTS

ОСНОВНЫЕ ТЕРМИНЫ И ПОНЯТИЯ

sluice gate water pressure and reaction force

Sluice gates control water flow in channels, reservoirs, and irrigation systems. They work as vertical barriers with an opening that can be raised or lowered. Changing the opening height changes the water velocity and pressure below the gate.

The forces on a sluice gate depend on the water depths upstream and downstream, written as z1 and z2. When the gate is closed, the upstream water depth is greater. That creates a strong pressure difference across the gate and a net force toward the downstream side. In that case, the gate needs an anchoring system to keep it secure.

The pressure on the upstream side is hydrostatic pressure, which depends on water depth and gravity. The downstream pressure depends on z2. Together, these pressures create the pressure gradient that pushes on the gate.

When the sluice gate is partially open, water flows beneath it. Bernoulli's principle can then be used to find the downstream velocity, V2, from the upstream and downstream depths. As the water moves through the opening instead of building up, the pressure difference becomes smaller and the reaction force on the gate decreases. The total reaction force is therefore highest when the gate is fully closed and lower as the gate opens.

Sluice Gate Water Pressure and Reaction Force

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design example: forces in sluice gate

Sluice gates control water flow in channels, reservoirs, and irrigation systems. They work as vertical barriers with an opening that can be raised or lowered. Changing the opening height changes the water velocity and pressure below the gate. The forces on a sluice gate depend on the water depths upstream and downstream, written as z1 and z2. When the gate is closed, the upstream water depth is greater. That creates a strong pressure difference across the gate and a net force toward the...

key terms and concepts

Learn how upstream and downstream water depths affect pressure, flow speed, and reaction force on a sluice gate when it is closed or partially open.

Sluice Gate Water Pressure and Reaction Force | JoVE K12

JoVE Core Civil Engineering provides a foundational exploration of essential construction materials in civil engineering, focusing on bricks, stones, steel, wood, and concrete through easy-to-understand animated videos. This collection covers the properties, manufacturing processes, and practical applications of these materials. Additionally, the accompanied science-in-action videos demonstrate the research experiments performed in laboratories.

Sluice Gate Water Pressure and Reaction Force

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