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

Fluid pressure is measured using liquid columns in tubes, either vertically or at an inclination, termed manometers. The height of the liquid column determines the pressure difference.
The simplest manometer is a piezometer tube used to measure pressure. It is a vertical tube open at the top and connected to a container, using the same fluid to indicate the pressure in the tube.
Another commonly used manometer is the U-tube manometer, which consists of a U-shaped tube connected to the fluid source. It contains a different fluid, called the gauge fluid, which does not mix with the fluid whose pressure is being measured.
The inclined-tube manometer has one leg inclined, containing gauge fluid that does not mix with the measured fluid, and the pressure difference is read along the incline for increased sensitivity.
U-tube and inclined-tube manometers are commonly used to measure the pressure difference between two containers or points within a system.
Other pressure gauges include the Bourdon gauge, which measures the pressure of fluids or gases, and the aneroid barometer, which measures atmospheric pressure.

measurement of fluid pressure

Measurement of Fluid Pressure

Fluid pressure is commonly measured using devices called manometers, which rely on liquid columns to indicate pressure differences. The height of a liquid column in a manometer reflects the pressure exerted by the fluid, providing a simple yet effective means of measurement. Different types of manometers serve specific purposes based on their configurations and the type of fluids involved.
A basic form of manometer is the piezometer, a vertical tube open at the top and filled with the same fluid whose pressure is measured. When connected to a fluid container, the height of the fluid in the tube correlates directly with the pressure inside the container. For more complex applications, the U-tube manometer uses a U-shaped tube filled with a gauge fluid that does not mix with the fluid being measured. This setup allows for differential pressure measurements between two points.
Another variant is the inclined-tube manometer, which has one leg tilted. This inclined leg enhances sensitivity by stretching the measurement scale along the incline, allowing for precise readings of small pressure differences.
Beyond manometers, there are other tools for measuring fluid and atmospheric pressure. The Bourdon gauge, for instance, is widely used to measure gas or liquid pressures in various industrial applications, while the aneroid barometer measures atmospheric pressure and is commonly used in weather forecasting and altitude measurements.

Fluid pressure is measured using liquid columns in tubes, either vertically or at an inclination, termed manometers. The height of the liquid column ...

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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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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

Learn how piezometers, U-tube and inclined manometers, Bourdon gauges, and aneroid barometers measure fluid and atmospheric pressure in practical settings.

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Manometers and Gauges for Fluid Pressure

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