Name: manometers and gauges for fluid pressure
Uploaded: 2025-02-13T15:43:11.000Z
Duration: 1 min 16 s
Channel: JoVE

La pression du fluide est mesurée à l’aide de colonnes de liquide dans des tubes, soit verticalement, soit à une inclinaison, appelées manomètres. La hauteur de la colonne de liquide détermine la différence de pression.
Le manomètre le plus simple est un tube piézomètre utilisé pour mesurer la pression. Il s’agit d’un tube vertical ouvert par le haut et relié à un récipient, en utilisant le même fluide pour indiquer la pression dans le tube.
Un autre manomètre couramment utilisé est le manomètre à tube en U, qui se compose d’un tube en forme de U connecté à la source de fluide. Il contient un fluide différent, appelé fluide manométrique, qui ne se mélange pas au fluide dont la pression est mesurée.
Le manomètre à tube incliné a une jambe inclinée, contenant le liquide manométrique qui ne se mélange pas au fluide mesuré, et la différence de pression est lue le long de l’inclinaison pour une sensibilité accrue.
Les manomètres à tube en U et à tube incliné sont couramment utilisés pour mesurer la différence de pression entre deux récipients ou points au sein d’un système.
Parmi les autres manomètres, citons le manomètre Bourdon, qui mesure la pression des fluides ou des gaz, et le baromètre anéroïde, qui mesure la pression atmosphérique.

mesure de la pression des fluides

Measurement of Fluid Pressure

La pression des fluides est généralement mesurée à l'aide d'appareils appelés manomètres, qui s'appuient sur des colonnes de liquide pour indiquer les différences de pression. La hauteur d'une colonne de liquide dans un manomètre reflète la pression exercée par le fluide, offrant un moyen de mesure simple mais efficace. Différents types de manomètres servent à des fins spécifiques en fonction de leurs configurations et du type de fluides concernés.

Une forme de base de manomètre est le piézomètre, un tube vertical ouvert en haut et rempli du même fluide dont la pression est mesurée. Lorsqu'il est connecté à un récipient de fluide, la hauteur du fluide dans le tube est directement corrélée à la pression à l'intérieur du récipient. Pour des applications plus complexes, le manomètre à tube en U utilise un tube en forme de U rempli d'un fluide de jauge qui ne se mélange pas au fluide mesuré. Cette configuration permet des mesures de pression différentielle entre deux points.

Une autre variante est le manomètre à tube incliné, dont un pied est incliné. Ce pied incliné améliore la sensibilité en étirant l'échelle de mesure le long de l'inclinaison, permettant des lectures précises de petites différences de pression.

Outre les manomètres, il existe d'autres outils permettant de mesurer la pression des fluides et de l'atmosphère. Le manomètre Bourdon, par exemple, est largement utilisé pour mesurer la pression des gaz ou des liquides dans diverses applications industrielles, tandis que le baromètre anéroïde mesure la pression atmosphérique et est couramment utilisé dans les prévisions météorologiques et les mesures d'altitude.

Mesure de la pression des fluides

La pression du fluide est mesurée à l’aide de colonnes de liquide dans des tubes, soit verticalement, soit à une inclinaison, appelées manomètres. La hauteur de la colonne de liquide ...

Education

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Fluid Statics

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manometers and gauges for fluid pressure

Fluid pressure is measured with manometers and related gauges. These tools use a liquid column to show pressure differences. The height of the column gives a simple reading of the force the fluid exerts.

A basic manometer is the piezometer. It is a vertical tube that is open at the top and filled with the same fluid being measured. When the tube connects to a container, the fluid height in the tube matches the pressure inside that container.

For more detailed measurements, the U-tube manometer is used. It has a U-shaped tube filled with a gauge fluid that does not mix with the fluid being measured. This setup is useful for measuring the pressure difference between two points.

The inclined-tube manometer is another form of manometer. One leg of the tube is tilted. This incline makes the scale stretch out, so it is easier to read very small pressure differences.

Other pressure tools are also used in practice. The Bourdon gauge measures gas or liquid pressure in many industrial settings. The aneroid barometer measures atmospheric pressure and is used in weather forecasting and altitude measurements.

Manometers and Gauges for Fluid Pressure

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measurement of fluid pressure

Fluid pressure is measured with manometers and related gauges. These tools use a liquid column to show pressure differences. The height of the column gives a simple reading of the force the fluid exerts. A basic manometer is the piezometer. It is a vertical tube that is open at the top and filled with the same fluid being measured. When the tube connects to a container, the fluid height in the tube matches the pressure inside that container. For more detailed measurements, the U-tube...

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key terms and concepts

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Manometers and Gauges for Fluid Pressure

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