Name: pressure balance in a fluid element
Uploaded: 2025-02-13T15:43:11.000Z
Duration: 1 min 13 s
Channel: JoVE

Considere un pequeño elemento fluido rectangular con las longitudes de los bordes supuestas como tomadas de cualquier ubicación arbitraria dentro de la masa fluida de interés.
Dos tipos de fuerzas actúan sobre este elemento, incluidas las fuerzas superficiales causadas por la presión y una fuerza corporal igual al peso del elemento.
Si la presión se denota en el centro del elemento como p, la presión promedio en las diferentes caras se puede describir en términos de p y sus derivados.
Para comprender el efecto de las fuerzas sobre el elemento fluido, la fuerza superficial resultante en la dirección y se puede expresar, y de manera similar, para las superficies x y z.
La fuerza superficial resultante que actúa sobre el elemento ahora se puede representar en forma vectorial y expresar aún más como la fuerza superficial resultante por unidad de volumen.
El peso del elemento se puede expresar utilizando el peso específico del fluido.
La segunda ley de Newton para el elemento fluido se puede expresar utilizando la fuerza superficial resultante por unidad de volumen y el peso del elemento.
Con esto, se puede obtener la ecuación del campo de presión.

ecuación básica para el campo de presión

Basic Equation for Pressure Field

La ecuación básica para un campo de presión en mecánica de fluidos captura el equilibrio de fuerzas dentro de cualquier segmento de fluido, lo que proporciona una comprensión fundamental de cómo cambia la presión dentro de los fluidos bajo diversas fuerzas. En general, dos tipos principales de fuerzas actúan sobre cualquier parte de un fluido: fuerzas superficiales y fuerzas corporales. Las fuerzas superficiales surgen de las diferencias de presión en los puntos dentro del fluido, que dan como resultado fuerzas netas que pueden variar según el gradiente de presión local. Las fuerzas corporales, por otro lado, se distribuyen por todo el fluido y surgen principalmente de la gravedad que actúa sobre la masa del fluido. La ecuación del campo de presión se deriva del análisis de estas fuerzas en combinación con la segunda ley de Newton, que vincula la fuerza con la aceleración de la masa del fluido. Esta ecuación ofrece una visión simplificada de cómo las fuerzas interactúan para crear variaciones de presión dentro de un fluido. Cuando la presión aumenta o disminuye en un fluido, a menudo conduce a un movimiento o aceleración, impulsados ​​por este equilibrio de fuerzas. La ecuación del campo de presión es esencial para comprender el comportamiento de los fluidos, desde el flujo en ríos y tuberías hasta los cambios de presión atmosférica y los patrones climáticos. Al comprender cómo se distribuye la presión dentro de un fluido, se puede predecir el movimiento del fluido y se pueden diseñar sistemas para gestionar el flujo en aplicaciones que van desde maquinaria hidráulica hasta redes de distribución de agua e incluso aerodinámica.

Ecuación básica para el campo de presión

Considere un pequeño elemento fluido rectangular con las longitudes de los bordes supuestas como tomadas de cualquier ubicación arbitraria dentro de la masa fluida de ...

Education

Educación

JoVE Core

Civil Engineering

Ingeniería Civil

Unit 1

Unidad 1

Fluid Statics

Estática de Fluidos

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

pressure balance in a fluid element

The pressure field equation describes how forces stay balanced inside a small fluid element. In fluid mechanics, this balance helps explain how pressure changes from one place to another within a fluid.

Two main force types act on a fluid segment: surface forces and body forces. Surface forces come from pressure differences across nearby points in the fluid, so they depend on the local pressure gradient, which is the rate of pressure change with position. Body forces are spread through the fluid, and gravity is the main example because it acts on the fluid’s mass.

The pressure field equation is derived by combining these forces with Newton’s second law, which connects force and acceleration. The result gives a simplified way to see how pressure variations form in a fluid. When pressure increases or decreases across the fluid, the force balance can lead to motion or acceleration.

This idea is useful for understanding fluid behavior in rivers and pipes, as well as atmospheric pressure changes and weather patterns. It also helps predict fluid movement and support the design of systems such as hydraulic machinery, water distribution networks, and aerodynamics applications.

Pressure Balance in a Fluid Element

concept of pressure at a point

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Fluid pressure at one point is the focus of this lesson. It shows that pressure in a fluid is the same in every direction at a single location. This happens because fluid molecules move randomly and collide with nearby molecules in a balanced way. At a given point, the pressure depends on the surrounding fluid molecules. It is affected by depth and density, not by the shape of the container or the way the fluid is oriented. In a fluid at rest, the pressure acts equally in all directions...

basic equation for pressure field

The pressure field equation describes how forces stay balanced inside a small fluid element. In fluid mechanics, this balance helps explain how pressure changes from one place to another within a fluid. Two main force types act on a fluid segment: surface forces and body forces. Surface forces come from pressure differences across nearby points in the fluid, so they depend on the local pressure gradient, which is the rate of pressure change with position. Body forces are spread through the...

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Manometers and Gauges for Fluid Pressure

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buoyancy and stability for submerged and floating bodies

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How Buoyancy Keeps Bodies Stable in Water

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design example: application of archimedes' principle

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Floating Block Buoyancy and Center of Buoyancy

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key terms and concepts

Learn how surface forces, body forces, and Newton’s second law combine to explain pressure changes in fluids, from pipes to weather patterns.

Pressure Balance in a Fluid Element | 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.

civil engineering

Pressure Balance in a Fluid Element

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