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

Si considerino le superfici piane immerse in un fluido con un peso specifico. Le forze si sviluppano sulle superfici a causa del fluido.
La risultante delle forze sviluppate sulla superficie orizzontale è data dal prodotto della pressione esercitata dal fluido sulla superficie e dell'area della superficie che agisce attraverso il baricentro dell'area.
La risultante delle forze sulla superficie verticale è data dal prodotto del peso specifico del fluido, dell'area della superficie verticale e della profondità del baricentro dell'area dalla superficie del fluido.
Per una superficie sommersa inclinata, la forza che agisce su un piccolo elemento è il prodotto del peso specifico del fluido, della profondità dell'elemento dalla superficie del fluido e della sua area.
L'integrazione della forza che agisce sulla toppa fornisce la risultante della pressione che agisce sull'intera superficie inclinata.
La risultante sembra agire attraverso il baricentro, ma in realtà agisce attraverso il punto sotto il baricentro chiamato centro di pressione.

forza di pressione idrostatica su una superficie piana

Quando una superficie piana è immersa in un fluido, si sviluppano forze idrostatiche sulla superficie, a causa della pressione del fluido. Per le superfici orizzontali, la pressione esercitata dal fluido è uniforme, perché la profondità rimane costante. La forza risultante è determinata dalla pressione alla profondità data, moltiplicata per l'area della superficie che agisce attraverso il baricentro della superficie. Per le superfici verticali, la pressione varia con la profondità, aumentando all'aumentare della distanza dalla superficie libera del fluido. La forza risultante è calcolata come il prodotto fra il peso specifico del fluido, l'area della superficie verticale e la profondità del baricentro dalla superficie del fluido.

Nel caso di una superficie inclinata, la forza che agisce su ogni piccolo elemento della superficie, è influenzata dalla sua profondità e dal peso specifico del fluido. Per calcolare la forza totale, vengono integrati i contributi di tutti gli elementi della superficie. Sebbene possa sembrare che la forza risultante agisca attraverso il baricentro della superficie, in realtà agisce attraverso un punto chiamato centro di pressione, che si trova sotto il baricentro. Questo è il punto in cui si può considerare che agisca la pressione idrostatica totale.

Forza di Pressione Idrostatica su una Superficie Piana

Si considerino le superfici piane immerse in un fluido con un peso specifico. Le forze si sviluppano sulle superfici a causa del fluido.
Il risultato del ...

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

Education

Didattica

JoVE Core

Civil Engineering

Ingegneria Civile

Unit 1

Unità 1

Fluid Statics

Statica dei fluidi

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

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

Fluid Pressure at One Point

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

Pressure Balance in a Fluid Element

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Hydrostatic Pressure and Fluid Depth

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measurement of fluid pressure

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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

Buoyancy and stability explain how submerged and floating bodies behave in a fluid. When a body is fully or partly under water and stays still, the fluid pushes upward on it. That upward push is called the buoyant force. The buoyant force acts through the center of buoyancy. This is the center of the displaced fluid volume. Archimedes’ principle says the buoyant force equals the weight of the fluid displaced by the body. Stability describes whether a body can return to its original position...

design example: application of archimedes' principle

design-example-application-of-archimedes-principle

Floating Block Buoyancy and Center of Buoyancy

Archimedes' principle is used to analyze the buoyant force on a wooden block that floats in seawater. The block has a rectangular section, and its dimensions, specific gravity, and the specific weight of seawater are used in the calculation. This setup shows how floating bodies stay in equilibrium. The first step is to find the weight of the block from its volume and specific gravity. Then Archimedes' principle is applied. The weight of the displaced water must equal the weight of the block.

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

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.

Hydrostatic Pressure on Submerged Surfaces

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