Name: bernoulli's principle in fluid devices
Uploaded: 2023-05-16T08:18:41.000Z
Duration: 1 min 17 s
Channel: JoVE

El principio de Bernoulli tiene varias aplicaciones prácticas, como los quemadores Bunsen, los frascos de perfume y las boquillas de las mangueras contra incendios.
Un tubo venturi es una de esas aplicaciones, que se utiliza para medir la velocidad de un fluido que fluye en una tubería.
Consta de una parte convergente, la garganta, y una parte divergente.
Dos tubos verticales delgados están conectados a un tubo venturi, uno antes de la parte convergente y otro en la región de la garganta.
Su funcionamiento se basa en la ecuación de continuidad y el principio de Bernoulli.
De acuerdo con la ecuación de continuidad, si el área de la sección transversal de la tubería disminuye, la velocidad del flujo debe aumentar.
Según el principio de Bernoulli, el aumento de la velocidad del flujo va acompañado de una disminución de la presión.
Por lo tanto, la presión cerca de la entrada es alta y la presión en el centro de la región de la garganta es baja. La diferencia de altura en el nivel de fluido en los tubos verticales es la medida de la diferencia de presión.
Si se conocen las áreas de la sección transversal, se pueden resolver estas ecuaciones para obtener la velocidad del fluido que fluye a través del tubo.

<ol>
	<li>OpenStax. (2019). Física Universitaria Vol. 1. [Versión web]. Recuperado de la sección 14.6, pp-719-720. <a href="https://openstax.org/books/university-physics-volume-1/pages/14-6-bernoullis-equation">https://openstax.org/books/university-physics-volume-1/pages/14-6-bernoullis-equation</a></li>
</ol>

principio de bernoulli: aplicaciones

Hay muchos dispositivos y situaciones en los cuales el fluido fluye a una altura constante y, por lo tanto, puede ser analizado utilizando el principio de Bernoulli. Estos dispositivos incluyen, pero no se limitan a, dispositivos de arrastre y dispositivos de medición de flujo de fluido. Los dispositivos de arrastre utilizan una alta velocidad de fluido para crear bajas presiones y, así, arrastrar un fluido en otro. Algunos ejemplos de estos dispositivos se presentan a continuación: <ol> <li>Un mechero Bunsen utiliza una boquilla de gas ajustable para arrastrar aire para una combustión adecuada.</li> <li>Un atomizador utiliza un bulbo de apretar para crear un chorro de aire que arrastra gotas de perfume.</li> <li>Los pulverizadores de pintura y los carburadores utilizan técnicas muy similares para mover sus respectivos líquidos.</li> <li>Un aspirador común utiliza un chorro de agua de alta velocidad para crear una región de baja presión. Los aspiradores se pueden utilizar como bombas de succión en situaciones dentales y quirúrgicas, para drenar un sótano inundado o para reducir la presión en un recipiente.</li> <li>La chimenea de un calentador de agua está diseñada para arrastrar aire hacia el conducto que atraviesa el techo.</li> </ol> Algunos dispositivos utilizan el principio de Bernoulli para la medición de la velocidad del fluido. Ejemplos de estos dispositivos incluyen los tubos de Prandtl, también conocidos como tubos de Pitot, los tubos de Venturi y un manómetro conectado a dos tubos que están cerca uno del otro y son lo suficientemente pequeños como para no perturbar el flujo.

Principio de Bernoulli: aplicaciones

Hay muchos dispositivos y situaciones en los que el fluido fluye a una altura constante y, por lo tanto, se pueden analizar utilizando el principio de Bernoulli. Estos dispositivos ...

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Physics

Física

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Fluid Mechanics

Mecánica de fluidos

KEY TERMS AND CONCEPTS

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Bernoulli's Principle: Applications

bernoulli's principle in fluid devices

Bernoulli's principle helps explain how many fluid devices work when the fluid moves at a constant height. It is useful for devices that use fast flow to create low pressure and for devices that measure fluid speed.

Some devices use this pressure change to pull one fluid into another. These are called entrainment devices. A Bunsen burner uses an adjustable gas nozzle to entrain air for proper combustion. An atomizer uses a squeeze bulb to make a jet of air that pulls perfume drops into the flow. Paint sprayers and carburetors work in a very similar way to move their liquids.

Other examples include a common aspirator, which uses a high-speed stream of water to create a lower-pressure region. Aspirators can act as suction pumps in dental and surgical settings. They can also help drain a flooded basement or reduce the pressure in a vessel. A water heater chimney is also designed to entrain air into the pipe leading through the ceiling.

Bernoulli's principle is also used to measure fluid speed. Prandtl tubes, also called pitot tubes, Venturi tubes, and a manometer connected to two close tubes can all be used for this purpose. The tubes must be close together and small enough not to disturb the flow.

Bernoulli's Principle in Fluid Devices

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density

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pascal's law

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buoyancy

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bernoulli's principle

Fluid Pressure and Speed Changes

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bernoulli's principle: applications

Bernoulli's principle helps explain how many fluid devices work when the fluid moves at a constant height. It is useful for devices that use fast flow to create low pressure and for devices that measure fluid speed. Some devices use this pressure change to pull one fluid into another. These are called entrainment devices. A Bunsen burner uses an adjustable gas nozzle to entrain air for proper combustion. An atomizer uses a squeeze bulb to make a jet of air that pulls perfume drops into the...

energy conservation and bernoulli's equation

energy-conservation-and-bernoulli-s-equation

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viscosity

Viscosity and How Fluids Flow

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stokes' law

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key terms and concepts

See how Bernoulli's principle explains entrainment devices and fluid speed tools like Bunsen burners, aspirators, pitot tubes, and Venturi tubes.

Bernoulli's Principle in Fluid Devices | JoVE K12

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Bernoulli's Principle in Fluid Devices

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