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

闸门是一种垂直屏障，用于控制渠道中的水流。
为了计算作用在闸门上的力，需考虑水流从闸门下方流过的情况。
这些力取决于上游和下游的水深。
上游侧水深为 z1，下游侧水深为 z2。
两侧之间的压力差在闸门上产生一个净力。
根据伯努利原理，可通过压力差和高度下降来计算闸门下方水流的速度 V2。
作用在闸门上的反作用力由两侧水柱产生的静水压力计算得出。
当阀门关闭时，由于压力差更大，作用力也更大。
当闸门打开时，水流在闸门下方自由流动，导致反作用力减小，净静水压差也随之降低。
这一原理可用于确定在运行过程中为保持闸门就位所需的锚固力。

设计示例：水闸中的力

Design Example: Forces in Sluice Gate

在水利工程中，水闸对于管理通过渠道、水库和灌溉系统的水流至关重要。水闸充当垂直屏障，通过调整闸门的开启高度来调节水流，从而改变闸门下方水流的速度和压力。了解所涉及的力对于设计能够承受动态压力差的水闸至关重要，尤其是在闸门关闭或部分打开时。 分析水闸力的关键变量包括上游深度 z1 和下游深度 z2。当闸门关闭时，上游侧的水深较大，从而在闸门上产生显著的压差。这种压差会产生净力，这需要锚固系统将闸门牢固地固定到位。施加在上游侧的静水压力与水深和重力成正比，而下游压力取决于 z2。由此产生的跨闸压力梯度会产生一个净力，推向下游侧。 当闸门部分打开时，水从闸门下方流动，可用伯努利原理确定下游速度 V2. <img alt="Equation 1" src="/files/ftp_upload/18056/18056_Equation_1.svg" style="text-align: center; height: 90px;"> 给定上游和下游深度，该原理将由于水位差异而导致的压力变化联系起来，从而可以根据高度差和压力梯度计算 V2。这种流动通过允许移动而不是累积来降低施加在闸门上的压力，从而减少水自由流动时的净力。 闸门上的总反作用力主要受上游水柱的静水力影响，当闸门完全关闭时，静水力达到最高。当闸门打开并且水从闸门下方流动时，压差的减小会降低反作用力。 <img alt="Equation 2" src="/files/ftp_upload/18056/18056_Equation_2.svg" style="text-align: center; height: 90px;">

sluice gate 是一种垂直屏障，用于控制渠道中的水流。  
为计算作用在 sluice gate 上的力，需考虑从其下方流过的水流……

Education

教育

JoVE Core

Civil Engineering

土木工程

Unit 1

第一单元

Finite Control Volume Analysis

有限控制体分析

KEY TERMS AND CONCEPTS

关键术语与概念

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...

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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.

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civil engineering

Sluice Gate Water Pressure and Reaction Force

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