Name: hydrostatic pressure on submerged surfaces
Uploaded: 2025-02-13T15:43:11.000Z
Duration: 1 min 4 s
Channel: JoVE

Considérons les surfaces planes immergées dans un fluide avec un poids spécifique. Des forces se développent sur les surfaces à cause du fluide.
La résultante des forces développées sur la surface horizontale est donnée par le produit de la pression exercée par le fluide sur la surface et de l’aire de la surface agissant à travers le centroïde de l’aire.
La résultante des forces sur la surface verticale est donnée par le produit du poids spécifique du fluide, de l’aire de la surface verticale et de la profondeur du centroïde de l’aire de la surface du fluide.
Pour une surface immergée inclinée, la force agissant sur un petit élément est le produit du poids spécifique du fluide, de la profondeur de l'élément par rapport à la surface du fluide et de sa surface.
L’intégration de la force agissant sur le patch donne le résultat de la pression agissant sur toute la surface inclinée.
La résultante semble agir à travers le centroïde, mais elle agit en fait à travers le point situé sous le centroïde appelé centre de pression.

force de pression hydrostatique sur une surface plane

Lorsqu'une surface plane est immergée dans un fluide, des forces hydrostatiques se développent à la surface en raison de la pression du fluide. Pour les surfaces horizontales, la pression exercée par le fluide est uniforme car la profondeur reste constante. La force résultante est déterminée par la pression à la profondeur donnée multipliée par la surface de la surface, et elle agit par l'intermédiaire du centre de gravité de la surface. Pour les surfaces verticales, la pression varie avec la profondeur, augmentant à mesure que la distance par rapport à la surface libre du fluide augmente. La force résultante est calculée comme le produit du poids spécifique du fluide, de la surface de la surface verticale et de la profondeur du centre de gravité par rapport à la surface du fluide.

Dans le cas d'une surface inclinée, la force agissant sur chaque petit élément de la surface est influencée par sa profondeur et le poids spécifique du fluide. Pour trouver la force totale, les contributions de tous les éléments de la surface sont intégrées. Bien qu'il puisse sembler que la force résultante agissant par l'intermédiaire du centre de gravité de la surface, elle agit en fait par l'intermédiaire d'un point appelé centre de pression, qui est situé sous le centre de gravité. C'est à ce point que l'on peut considérer que la pression hydrostatique totale agit.

Force de pression hydrostatique sur une surface plane

Considérons les surfaces planes immergées dans un fluide avec un poids spécifique. Des forces se développent sur les surfaces à cause du fluide.
Le résultat de la ...

hydrostatic-pressure-force-on-a-plane-surface

Education

Enseignement

JoVE Core

Civil Engineering

Génie civil

Unit 1

Unité 1

Fluid Statics

Statique des fluides

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

Hydrostatic Pressure Force on a Plane Surface

hydrostatic pressure on submerged surfaces

Hydrostatic pressure creates force on submerged plane surfaces. The force depends on the fluid pressure and the area of the surface. The way that force acts changes with the surface position.

For a horizontal surface, the depth stays the same across the whole area. That means the pressure is uniform. The resultant force equals the pressure at that depth multiplied by the surface area, and it acts through the centroid of the surface.

For a vertical surface, pressure increases as depth increases below the free surface. The resultant force is found from the fluid’s specific weight, the area of the vertical surface, and the depth of the centroid from the fluid surface. An inclined surface is handled by looking at small surface elements, each affected by its own depth and the fluid’s specific weight. The total force comes from adding, or integrating, all of those small contributions.

The resultant force does not act at the centroid in every case. It acts at the center of pressure, which is below the centroid. This is the point where the total hydrostatic pressure can be treated as acting.

Hydrostatic Pressure on Submerged Surfaces

hydrostatic-pressure-on-submerged-surfaces

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hydrostatic pressure force on a plane surface

Hydrostatic pressure creates force on submerged plane surfaces. The force depends on the fluid pressure and the area of the surface. The way that force acts changes with the surface position. For a horizontal surface, the depth stays the same across the whole area. That means the pressure is uniform. The resultant force equals the pressure at that depth multiplied by the surface area, and it acts through the centroid of the surface. For a vertical surface, pressure increases as depth...

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hydrostatic-pressure-force-on-a-curved-surface

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design-example-application-of-archimedes-principle

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key terms and concepts

Learn how hydrostatic pressure acts on horizontal, vertical, and inclined submerged surfaces, and why the center of pressure is below the centroid.

Hydrostatic Pressure on Submerged Surfaces | JoVE K12

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Hydrostatic Pressure on Submerged Surfaces

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