Name: pitot-static measurement in bernoulli flow
Uploaded: 2026-01-30T03:08:30.000Z
Duration: 1 min 24 s
Channel: JoVE

Das Bernoulli-Prinzip besagt, dass der Gesamtdruck entlang einer Stromlinie in einem Fluidsystem konstant bleibt und die Summe aus statischem, dynamischem und potenziellem Energiedruck ist.
Statischer Druck ist die Kraft, die von einer ruhenden Flüssigkeit ausgeübt wird und häufig in Rohrleitungen und Wasserversorgungssystemen beobachtet wird.
Sie hängt von der Höhe und Dichte des Fluids ab und wirkt senkrecht zur Oberfläche, die mit dem Fluid in Kontakt kommt.
Der dynamische Druck hängt mit der Geschwindigkeit des Fluids zusammen und stellt die Energie dar, die durch Bewegung entsteht.
Es ist entscheidend für die Planung von Systemen mit sich schnell bewegenden Flüssigkeiten, wie z. B. Regenwasserableitung oder Flusskanäle mit hoher Geschwindigkeit.
Ein Stagnationsdruck tritt auf, wenn das Fluid zur Ruhe gebracht wird, wobei statischer und dynamischer Druck kombiniert werden.
Sie wird an Stagnationspunkten wie Dammoberflächen oder Turbinenschaufeln gemessen, an denen die Geschwindigkeit des Fluids auf Null reduziert wird.
Das Verständnis des Gleichgewichts von statischem, dynamischem und stagnierendem Druck hilft bei der Bewältigung von Druckänderungen und Energie in Fluidsystemen.
Diese Drücke werden mit Geräten wie statischen Pitot-Rohren gemessen, die für die Berechnung der Luftgeschwindigkeit und der Strömung in verschiedenen Anwendungen des Bauwesens von entscheidender Bedeutung sind.

statischer, stagnierender, dynamischer und gesamtdruck

Das Konzept von statischem, stagnierendem, dynamischem und Gesamtdruck ist grundlegend in der Strömungsdynamik und wird oft mit der Bernoulli-Gleichung erklärt:

<img alt="Equation 1" src="/files/ftp_upload/18036/18036_Equation_1.svg" style="text-align: center; height: 26px;">

Hier ist p der statische Druck, 1/2⍴V^2 der dynamische Druck, γz der hydrostatische Druck oder der potentielle Energiedruck und p_T der Gesamtdruck, der bei inkompressiblen Strömungen entlang einer Stromlinie konstant ist.

<ol style="display: flex; flex-direction: column; gap: 10px;">

<li>Statischer Druck (p): Dies ist der Druck, der von einem ruhenden Fluid ausgeübt wird oder als ob ein fließendes Fluid in Bewegungsrichtung zum Stillstand gebracht würde. Er wird mit einer in die Strömung eingeführten Sonde oder mit einem Piezometerrohr gemessen.</li>

<li>Dynamischer Druck (1/2⍴V^2): Er stellt den Druckanstieg aufgrund der Geschwindigkeit des Fluids dar. Er kann als kinetische Energie pro Volumeneinheit des Fluids interpretiert werden.</li>

<li>Stagnationsdruck (p_s): Dies ist die Summe aus statischem und dynamischem Druck an einem Stagnationspunkt, an dem die Geschwindigkeit des Fluids Null wird:</li>

<img alt="Equation 2" src="/files/ftp_upload/18036/18036_Equation_2.svg" style="text-align: center; height: 26px;">

<li>Gesamtdruck (p_T): Dies ist die Summe aus statischem, dynamischem und hydrostatischem Druck. Entlang einer Stromlinie:</li>

</ol>

Ein Staurohr misst den Stagnationsdruck (p_s) und den statischen Druck (p). Durch Berechnung der Differenz kann die Geschwindigkeit des Fluids bestimmt werden:

<img alt="Equation 3" src="/files/ftp_upload/18036/18036_Equation_3.svg" style="text-align: center; height: 34px;">

Bei Anwendungen wie der Messung der Luftgeschwindigkeit in der Luftfahrt ist die Gewährleistung einer genauen Ausrichtung und Platzierung des Staurohrs von entscheidender Bedeutung. Eine Fehlausrichtung oder Verstopfung kann zu fehlerhaften Messwerten führen und die Betriebssicherheit beeinträchtigen.

Statischer, stagnierender, dynamischer und Gesamtdruck

Das Bernoulli-Prinzip besagt, dass der Gesamtdruck entlang einer Stromlinie in einem Fluidsystem konstant bleibt und die Summe aus statischen, dynamischen und ...

static-stagnation-dynamic-and-total-pressure

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Unit 1

Einheit 1

Fluid Dynamics

Strömungsmechanik

KEY TERMS AND CONCEPTS

ZENTRALE BEGRIFFE UND KONZEPTE

Static, Stagnation, Dynamic and Total Pressure

pitot-static measurement in bernoulli flow

Static pressure, dynamic pressure, stagnation pressure, and total pressure are key ideas in fluid dynamics. They are often explained with Bernoulli's equation. In that equation, p is static pressure, 1/2ρV^2 is dynamic pressure, γz is hydrostatic pressure or potential energy pressure, and pT is total pressure. For incompressible flow, the total pressure stays constant along a streamline.

Static pressure is the pressure a fluid exerts when it is at rest, or when flowing fluid is brought to rest in the direction of motion. It can be measured with a probe placed in the flow or with a piezometer tube. Dynamic pressure comes from the fluid's speed. It represents the pressure rise due to motion, and it can also be viewed as the kinetic energy per unit volume of the fluid.

Stagnation pressure is the pressure at a stagnation point, where the fluid velocity becomes zero. It equals the sum of static pressure and dynamic pressure. Total pressure includes static, dynamic, and hydrostatic pressure. Along a streamline, this total remains constant for incompressible flow.

A Pitot-static tube measures stagnation pressure and static pressure. The difference between these two readings can be used to determine fluid velocity. This measurement is important in applications such as airspeed sensing in aviation. For accurate results, the Pitot-static tube must be aligned and placed correctly, because misalignment or blockage can produce incorrect readings and affect safety.

Pitot-Static Measurement in Bernoulli Flow

pitot-static-measurement-in-bernoulli-flow

bernoulli's equation for flow along a streamline

bernoulli-s-equation-for-flow-along-a-streamline

Pressure and Speed in Bernoulli's Equation

Bernoulli's equation links pressure, speed, and height in a moving fluid along a streamline. It is used for incompressible, inviscid fluids under steady flow. The idea comes from applying Newton's second law to a small fluid element. That element feels forces from pressure differences, gravity, and changes in velocity. The resulting equation shows how fluid energy is shared. In the equation, P is pressure, ρ is fluid density, v is velocity, g is the acceleration due to gravity, and h is...

bernoulli's equation for flow normal to a streamline

bernoulli-s-equation-for-flow-normal-to-a-streamline

Pressure Changes Across Curved Streamlines

Bernoulli's equation for flow normal to a streamline describes how pressure changes across curved streamlines. When a fluid follows a curved path, the outer side of the curve experiences centrifugal force, which pushes the fluid outward. The pressure is therefore higher on the inner side, near the center of curvature, and lower farther out. The size of this pressure difference depends on the fluid's velocity and the radius of curvature. In flows with nearly straight streamlines, the pressure...

bernoulli's equation: problem solving

Venturi Meter Flow Rate from Pressure

A Venturi meter measures fluid flow rate in a pipeline by using pressure changes and Bernoulli's equation. In a sewage system, it can be used to determine wastewater flow rate by reading the pressure difference across the meter. The narrowed throat makes the fluid speed up, and that change in speed is linked to pressure drop. The first step is to find the cross-sectional areas of the pipe and the Venturi throat. These areas are needed to interpret the pressure difference shown on the pressure...

static, stagnation, dynamic and total pressure

Static pressure, dynamic pressure, stagnation pressure, and total pressure are key ideas in fluid dynamics. They are often explained with Bernoulli's equation. In that equation, p is static pressure, 1/2ρV^2 is dynamic pressure, γz is hydrostatic pressure or potential energy pressure, and pT is total pressure. For incompressible flow, the total pressure stays constant along a streamline. Static pressure is the pressure a fluid exerts when it is at rest, or when flowing fluid is brought to rest...

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...

continuity equation

Fluid Flow and Area Changes

Fluid flow and area changes are linked by the continuity equation. For a steady flow of an incompressible fluid in a confined system, the mass flow rate stays constant. This idea is useful in nozzles, syringes, and pipes where the cross-sectional area changes. The mass flow rate is written as an equation that connects density, area, and velocity. For incompressible flow, the density stays the same, so the equation becomes simpler. When the area gets smaller, the fluid speed must increase. When...

energy line and hydraulic gradient line

Fluid Head Profiles in Pipes and Channels

Fluid head profiles in pipes and channels show how pressure, speed, and height change in a flowing fluid. These profiles come from Bernoulli's equation for steady, incompressible, inviscid flow. In that equation, total head includes pressure head, velocity head, and elevation head. The energy line (EL) shows the total head available in the flow. It sits above the datum and includes all three energy parts. Under ideal conditions, the EL stays horizontal because the total energy does not change...

design example: designing water slide

Water Slide Speed and Bernoulli's Principle

Water slide speed is controlled by Bernoulli's principle and the height of the slide. Engineers use these ideas to keep the ride exciting while making sure the water stays safe for riders. As water moves downhill, gravity makes it speed up. The water at the bottom depends on the height it starts from. A taller slide gives the water more potential energy at the top. That energy changes into kinetic energy as the water descends, so the flow becomes faster. Bernoulli's principle helps describe...

key terms and concepts

Learn how static, dynamic, stagnation, and total pressure relate to Bernoulli's equation and how a Pitot-static tube can be used to measure flow speed.

Pitot-Static Measurement in Bernoulli Flow | 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

Pitot-Static Measurement in Bernoulli Flow

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