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

O princípio de Bernoulli tem várias aplicações práticas, como bicos de Bunsen, frascos de perfume e bicos de mangueira de incêndio.
Um tubo venturi é uma dessas aplicações, usada para medir a velocidade de um fluido que flui em um tubo.
Consiste em uma parte convergente, a garganta, e uma parte divergente.
Dois tubos verticais finos são conectados a um tubo venturi - um antes da parte convergente e outro na região da garganta.
Seu funcionamento é baseado na equação de continuidade e no princípio de Bernoulli.
De acordo com a equação de continuidade, se a área da seção transversal do tubo diminuir, a velocidade do fluxo deve aumentar.
De acordo com o princípio de Bernoulli, o aumento da velocidade do fluxo é acompanhado por uma diminuição da pressão.
Portanto, a pressão perto da entrada é alta e a pressão no centro da região da garganta é baixa. A diferença de altura no nível de fluido nos tubos verticais é a medida da diferença de pressão.
Se as áreas da seção transversal forem conhecidas, pode-se resolver essas equações para obter a velocidade do fluido que flui através do tubo.

<ol>
	<li>OpenStax. (2019). Física Universitária Vol. 1. [Versão Web]. Obtido da seção 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>

princípio de bernoulli: aplicações

Existem muitos dispositivos e situações nas quais o fluido flui em uma altura constante e, por isso, pode ser analisado utilizando o princípio de Bernoulli. Estes dispositivos incluem, mas não estão limitados a, dispositivos de arrasto (entrainment) e dispositivos de medição do fluxo de fluido.

Dispositivos de arrasto usam uma alta velocidade do fluido para criar baixas pressões e, assim, arrastar um fluido para dentro de outro. Alguns exemplos desses dispositivos são apresentados abaixo:

<ol>
	<li>Um queimador de Bunsen usa um bico de gás ajustável para arrastar ar para uma combustão adequada.</li>
	<li>Um atomizador usa um bulbo de compressão para criar um jato de ar que arrasta gotas de perfume.</li>
	<li>Sprays de tinta e carburadores usam técnicas muito similares para mover seus respectivos líquidos.</li>
	<li>Um aspirador comum usa um fluxo de água em alta velocidade para criar uma região de menor pressão. Os aspiradores podem ser usados como bombas de sucção em situações dentárias e cirúrgicas, para drenar um porão alagado ou para reduzir a pressão em um recipiente.</li>
	<li>A chaminé de um aquecedor de água é projetada para arrastar ar para dentro do tubo que passa pelo teto.</li>
</ol>

Alguns dispositivos usam o princípio de Bernoulli para medir a velocidade do fluido. Exemplos desses dispositivos incluem tubos de Prandtl, também conhecidos como tubos de Pitot, tubos de Venturi e um manômetro conectado a dois tubos próximos e pequenos o suficiente para não perturbar o fluxo.

Princípio de Bernoulli: Aplicações

Existem muitos dispositivos e situações em que o fluido flui a uma altura constante e, portanto, pode ser analisado usando o princípio de Bernoulli. Esses dispositivos ...

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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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bernoulli's principle

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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...

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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

physics

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Bernoulli's Principle in Fluid Devices

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