Name: liquid speed from reservoir outlets
Uploaded: 2026-01-30T03:08:28.000Z
Duration: 1 min 14 s
Channel: JoVE

Serbest jetler, akışkan bir nozuldan çıkarken ve havaya serbestçe akarken, Bernoulli denklemi tarafından tanımlanan akışkan davranışını gösterir.
Nozuldaki akış hızı, potansiyel enerjiyi kinetik enerjiye dönüştüren üzerindeki sıvı kolonunun yüksekliği ile belirlenir.
Jetiğin çıkış basıncı atmosferik basınçla eşleşir ve sıvı büyük bir rezervuardan akarken hız artar.
Akışkan ataleti nedeniyle, jet nozülün hemen dışında daralır ve en küçük kesit alanını oluşturur. Bu fenomen vena contracta olarak bilinir.
Jetin vena kontraktasındaki alanı ile nozul alanının oranı kasılma katsayısını verir.
Bıçak sırtı, iyi yuvarlak, keskin kenarlı ve yeniden giriş tasarımları gibi çeşitli nozul şekilleri, akış modelini ve büzülme katsayısını etkiler.
Dolusavaklar ve savaklar gibi sistemlerin tasarımında, doğru akış ölçümü için vena contracta etkisi dikkate alınır.
Serbest jetler, sıvı akışını kontrol etmek ve yapısal etkiyi en aza indirmek için inşaat mühendisliği uygulamalarında çok önemlidir.

serbest jet

Serbest jetler, bir rezervuardan atmosfere bir açıklıktan dirençsiz bir şekilde çıkan sıvı akışını tanımlar. Sıvı jetinin hızı (V), Bernoulli ilkesi kullanılarak türetilir ve şu şekilde ifade edilir:

<img alt="Equation 1" src="/files/ftp_upload/18037/18037_Equation_1.svg" style="text-align: center; height: 15px;">

 Burada h, sıvının açıklığın üzerindeki yüksekliğidir. Bu ilişki, hem rezervuar yüzeyinde hem de jet çıkışında atmosfer basıncını varsayar. Sıvı sütununun yüksekliği, sıvının bir rezervuardaki nozuldaki hızını yönetir; burada sıvının potansiyel enerjisi akış sırasında kinetik enerjiye dönüşür.

 Vena contracta olgusu, sıvı keskin kenarlı bir delikten çıktığında meydana gelir ve bu da jet çapı dj'nin nozul çapından daha küçük olmasına neden olur. Bunun nedeni, sıvı akış çizgilerinin ani kenarları takip edememesi ve daralmış bir akış bölgesi oluşturmasıdır. Büzülme katsayısı, jetin vena contracta'daki kesit alanının nozulun kesit alanına oranıdır ve jet büzülmesinin derecesini belirler. Bu parametre, bıçak ağızlı, keskin ağızlı, iyi yuvarlatılmış ve yeniden girişli nozullar gibi çeşitli tasarımların farklı akış desenleri ve büzülme özellikleri üretmesiyle nozulun geometrisinden etkilenir. İyi yuvarlatılmış bir nozul için C_c = 1,0 iken, keskin veya bıçak ağızlı delikler C_c'yi yaklaşık 0,61'e düşürür. Yeniden girişli nozullar daha da düşük değerler sergiler.

 Bu akış özellikleri ve büzülme etkileri, rezervuarlardan endüstriyel nozullara kadar sıvı deşarjını içeren mühendislik uygulamalarında kritik öneme sahiptir.

Serbest Jet

Serbest jetler, akışkan bir nozuldan çıkarken ve havaya serbestçe akarken, Bernoulli denklemi tarafından tanımlanan akışkan davranışını gösterir.
Akış hızı ...

Education

JoVE Core

Civil Engineering

İnşaat Mühendisliği

Unit 1

Ünite 1

Fluid Dynamics

Akışkanlar Dinamiği

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

Free Jet

liquid speed from reservoir outlets

Free jets show how liquid moves after leaving a reservoir through an opening and flowing into the air without resistance. The jet speed is found with Bernoulli’s principle, and it depends on the height of liquid above the opening. This relationship assumes atmospheric pressure at both the reservoir surface and the jet exit.

The liquid column’s height controls the speed at the nozzle because the fluid’s potential energy changes into kinetic energy during flow. As the liquid leaves the reservoir, its motion reflects this energy conversion. This is why a deeper liquid level can produce a faster jet.

A sharp-edged orifice can also cause vena contracta, which is the narrowed region where the jet becomes smaller than the nozzle opening. This happens because the streamlines cannot follow the abrupt edge smoothly. The contraction coefficient measures this narrowing by comparing the jet area at vena contracta with the nozzle area.

Nozzle shape changes the flow pattern and the amount of contraction. Knife-edge, sharp-edge, well-rounded, and re-entrant nozzles each produce different results. For a well-rounded nozzle, the contraction coefficient is 1.0, while sharp or knife-edged openings reduce it to about 0.61, and re-entrant nozzles produce even lower values. These effects matter in engineering systems that discharge liquid from reservoirs and industrial nozzles.

Liquid Speed from Reservoir Outlets

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free jet

Free jets show how liquid moves after leaving a reservoir through an opening and flowing into the air without resistance. The jet speed is found with Bernoulli’s principle, and it depends on the height of liquid above the opening. This relationship assumes atmospheric pressure at both the reservoir surface and the jet exit. The liquid column’s height controls the speed at the nozzle because the fluid’s potential energy changes into kinetic energy during flow. As the liquid leaves the...

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key terms and concepts

Learn how liquid speed from a reservoir depends on height, Bernoulli’s principle, and nozzle shape, including vena contracta and contraction coefficient.

Liquid Speed from Reservoir Outlets | 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.

civil engineering

Liquid Speed from Reservoir Outlets

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