Name: how depth changes fluid pressure
Uploaded: 2023-09-22T11:49:33.000Z
Duration: 1 min 14 s
Channel: JoVE

La presión se define como la magnitud de la fuerza por unidad de área. Considerando un fluido incompresible, la fuerza se puede expresar en términos de peso específico o densidad del fluido.
Consideremos cuatro puntos en el agua. La presión es la misma para todos los puntos a la misma profundidad desde la superficie, pero menor a poca profundidad. La presión aumenta linealmente con la profundidad desde la superficie.
De acuerdo con la ley de Pascal, la intensidad de la presión en cualquier punto dado en un fluido estático incompresible es la misma en todas las direcciones.
Supongamos un elemento fluido infinitesimal en forma de cuña de ancho unitario. La fuerza en cada lado se expresa como el producto de la presión y el área.
Como el líquido está en reposo, la suma de los componentes horizontal y vertical de las fuerzas debe ser cero.
Tomando las componentes horizontales y usando relaciones trigonométricas, las ecuaciones se simplifican para obtener px igual a ps.
Del mismo modo, considerando las componentes verticales, las ecuaciones se simplifican para obtener py igual a p s. 
Por lo tanto, la presión en cualquier punto es la misma en todas las direcciones.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica: Estática. Decimocuarta edición, Nueva Jersey: Pearson. Págs. 512.</li>
</ol>

presión de fluidos

En la ingeniería mecánica, la presión de fluidos desempeña un papel crítico en el diseño de sistemas que utilizan flujo de líquido, como sistemas hidráulicos, bombas y válvulas. Al diseñar estos sistemas, los ingenieros deben asegurarse de que puedan resistir las fuerzas creadas por la presión de fluidos para evitar daños o fallas. Según la ley de Pascal, un fluido en reposo generará una presión igual en todas las direcciones. Esta presión se mide como una fuerza por unidad de área y su magnitud depende del peso específico o densidad de masa del fluido y la profundidad del punto de medición desde la superficie del fluido. Podemos expresar esta relación matemáticamente como p = ρgz, donde ρ es la densidad del fluido, g es la aceleración debido a la gravedad y z es la profundidad. Cabe destacar que la ecuación mencionada anteriormente es válida para fluidos incompresibles, como la mayoría de los líquidos, pero no para gases, cuya densidad cambia considerablemente con la temperatura y la presión. Para entender cómo se aplica esta ecuación a los líquidos, consideremos tres puntos ubicados dentro del agua. A la misma profundidad desde la superficie, la presión es idéntica para los tres puntos. Sin embargo, la presión es más baja en profundidades poco profundas. La presión aumenta linealmente con la profundidad a medida que uno se aleja de la superficie.

Presión de fluidos

En ingeniería mecánica, la presión del fluido desempeña un papel fundamental en el diseño de sistemas que utilizan el flujo de líquido, como sistemas hidráulicos, bombas ...

Education

Educación

JoVE Core

Mechanical Engineering

Ingeniería Mecánica

Unit 1

Unidad 1

Center of Gravity and Centroid

Centro de gravedad y centroide

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

Fluid Pressure

how depth changes fluid pressure

Fluid pressure changes with depth in liquids used in engineering systems. It matters in hydraulic systems, pumps, and valves, where the forces from moving and resting fluid must be considered to prevent damage or failure.

For a fluid at rest, Pascal’s law says the pressure is equal in all directions. Pressure is force per unit area. Its size depends on the fluid’s specific weight, or mass density, and on how deep the measurement point is below the fluid surface.

This relationship can be written as p = ρgz. In this equation, ρ is fluid density, g is the acceleration due to gravity, and z is depth. The equation applies to incompressible fluids, such as most liquids, but not to gases, because gas density can change greatly with temperature and pressure.

The pattern is easy to see in water. If three points are at the same depth, their pressure is the same. A point closer to the surface has lower pressure. As depth increases, pressure rises in a linear way.

How Depth Changes Fluid Pressure

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key terms and concepts

Explore how fluid pressure changes with depth, why Pascal’s law matters, and how the equation p = ρgz describes pressure in liquids like water.

How Depth Changes Fluid Pressure | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

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How Depth Changes Fluid Pressure

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