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

Una compuerta es una barrera vertical que controla el flujo de agua en un canal.
Para calcular las fuerzas que actúan sobre una compuerta, considere el agua que fluye debajo de la compuerta.
Las fuerzas dependen de las profundidades del agua aguas arriba y aguas abajo.
En el lado aguas arriba, la profundidad es z1, y en el lado aguas abajo, la profundidad es z2.
La diferencia de presión entre los dos lados crea una fuerza neta en la puerta.
Usando el principio de Bernoulli, la velocidad del agua debajo de la compuerta, V2, se puede calcular en función de la diferencia de presión y la caída de altura.
La fuerza de reacción en la compuerta se calcula a partir de la fuerza hidrostática que actúa debido a la columna de agua en ambos lados.
La fuerza es mayor cuando la puerta está cerrada debido a la mayor diferencia de presión.
Cuando se abre la compuerta, la fuerza de reacción disminuye a medida que el agua fluye libremente por debajo de la compuerta, lo que reduce la diferencia de presión hidrostática neta.
Este principio permite determinar la fuerza de anclaje necesaria para mantener la puerta en su lugar durante el funcionamiento.

ejemplo de diseño: fuerzas en una compuerta

Design Example: Forces in Sluice Gate

En ingeniería hidráulica, las compuertas son esenciales para controlar el flujo de agua a través de canales, embalses y sistemas de riego. Las compuertas, que actúan como barreras verticales, regulan el agua ajustando la altura de apertura de la compuerta, lo que cambia la velocidad y la presión del agua que fluye por debajo de la compuerta. Comprender las fuerzas involucradas es crucial para diseñar compuertas que puedan soportar diferencias de presión dinámica, especialmente cuando la compuerta está cerrada o parcialmente abierta. Las variables clave para analizar las fuerzas de la compuerta incluyen la profundidad aguas arriba z1 y la profundidad aguas abajo z2. Cuando la compuerta está cerrada, la profundidad del agua es mayor en el lado aguas arriba, lo que crea una diferencia de presión significativa a lo largo de la compuerta. Esta diferencia de presión produce una fuerza neta, que requiere un sistema de anclaje para mantener la compuerta firmemente en su lugar. La presión hidrostática ejercida en el lado aguas arriba es proporcional a la profundidad del agua y la fuerza gravitacional, mientras que la presión aguas abajo depende de z2. El gradiente de presión resultante a través de la compuerta crea una fuerza neta que empuja contra ella hacia el lado de aguas abajo. Cuando la compuerta está parcialmente abierta, el agua fluye por debajo de ella y el principio de Bernoulli se puede utilizar para determinar la velocidad de aguas abajo, V2. <img alt="Equation 1" src="/files/ftp_upload/18056/18056_Equation_1.svg" style="text-align: center; height: 90px;"> Dadas las profundidades aguas arriba y aguas abajo, el principio relaciona el cambio de presión debido a las diferencias en la altura del agua, lo que permite calcular V2 en función de las diferencias de altura y los gradientes de presión. Este flujo disminuye la presión ejercida sobre la compuerta al permitir el movimiento en lugar de la acumulación, lo que reduce la fuerza neta a medida que el agua fluye libremente. La fuerza de reacción total sobre la compuerta está influenciada principalmente por la fuerza hidrostática de la columna de agua aguas arriba, que es máxima cuando la compuerta está completamente cerrada. A medida que la compuerta se abre y el agua fluye por debajo de ella, la reducción en la diferencia de presión disminuye la fuerza de reacción. <img alt="Equation 2" src="/files/ftp_upload/18056/18056_Equation_2.svg" style="text-align: center; height: 90px;">

Ejemplo de diseño: Fuerzas en una compuerta

Una compuerta es una barrera vertical que controla el flujo de agua en un canal.
Para calcular las fuerzas que actúan sobre una compuerta, considere el agua que fluye por debajo ...

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JoVE Core

Civil Engineering

Ingeniería Civil

Unit 1

Unidad 1

Finite Control Volume Analysis

Análisis de Volumen de Control Finito

KEY TERMS AND CONCEPTS

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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.

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.

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Sluice Gate Water Pressure and Reaction Force

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