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

Considere superfícies planas submersas em um fluido com um peso específico. As forças são desenvolvidas nas superfícies por causa do fluido.
A resultante das forças desenvolvidas na superfície horizontal é dada pelo produto da pressão exercida pelo fluido na superfície e pela área da superfície atuando através do centróide da área.
A resultante das forças na superfície vertical é dada pelo produto do peso específico do fluido, a área da superfície vertical e a profundidade do centróide da área da superfície do fluido.
Para uma superfície submersa inclinada, a força que atua em um pequeno elemento é o produto do peso específico do fluido, da profundidade do elemento em relação à superfície do fluido e de sua área.
A integração da força que atua no remendo fornece a resultante da pressão que atua em toda a superfície inclinada.
A resultante parece estar agindo através do centróide, mas na verdade atua através do ponto abaixo do centróide chamado centro de pressão.

força de pressão hidrostática em uma superfície plana

Quando uma superfície plana é submersa em um fluido, forças hidrostáticas se desenvolvem na superfície devido à pressão do fluido. Para superfícies horizontais, a pressão exercida pelo fluido é uniforme porque a profundidade permanece constante. A força resultante é determinada pela pressão na profundidade dada multiplicada pela área da superfície e atua através do centroide da superfície. Para superfícies verticais, a pressão varia com a profundidade, aumentando conforme a distância da superfície livre do fluido aumenta. A força resultante é calculada como o produto do peso específico do fluido, a área da superfície vertical e a profundidade do centroide da superfície do fluido.

No caso de uma superfície inclinada, a força que atua em cada pequeno elemento da superfície é influenciada por sua profundidade e pelo peso específico do fluido. Para encontrar a força total, as contribuições de todos os elementos da superfície são integradas. Embora possa parecer que a força resultante atua através do centroide da superfície, ela, na verdade, atua via um ponto chamado centro de pressão, que está localizado abaixo do centroide. Este é o ponto onde a pressão hidrostática total pode ser considerada atuante.

Força de pressão hidrostática em uma superfície plana

Considere superfícies planas submersas em um fluido com um peso específico. As forças são desenvolvidas nas superfícies por causa do fluido.
O resultado do ...

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

Education

JoVE Core

Civil Engineering

Engenharia Civil

Unit 1

Unidade 1

Fluid Statics

Estática dos Fluidos

KEY TERMS AND CONCEPTS

TERMOS E CONCEITOS-CHAVE

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

concept of pressure at a point

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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...

hydrostatic pressure force on a curved surface

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

Finding the Force on Curved Fluid Surfaces

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buoyancy and stability for submerged and floating bodies

buoyancy-and-stability-for-submerged-and-floating-bodies

How Buoyancy Keeps Bodies Stable in Water

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design example: application of archimedes' principle

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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