Name: centrifugal pump flow rate calculation
Uploaded: 2025-02-13T15:43:22.000Z
Duration: 1 min 4 s
Channel: JoVE

Jeżeli trzeba obliczyć natężenie przepływu pompy odśrodkowej, która wywiera ciśnienie 7500 dżuli na sekundę w celu podniesienia wody ze zbiornika na niższym poziomie do zbiornika na wyższym poziomie, można użyć równania energii.
Różnica poziomów między zbiornikami wynosi 10 metrów, a ubytek ciśnienia wynosi 5 metrów.
Ponieważ powierzchnie obu zbiorników są otwarte na atmosferę, ciśnienie i prędkość zarówno na wlocie, jak i na wylocie wynoszą zero, co jeszcze bardziej upraszcza równanie energii.
W tym przypadku wysokość podnoszenia pompy uzyskuje się przez iloraz poboru mocy netto wału i iloczynu masy jednostkowej wody i natężenia przepływu.
Jeśli uproszczone równanie energii zostanie podstawione na wysokość podnoszenia pompy, można uzyskać natężenie przepływu pompy.
Ponadto podstawienie wartości podanych w wyrażeniu do natężenia przepływu daje wartość końcową wskazującą szybkość, z jaką pompowana jest woda.

zastosowanie równania energii

Zastosowanie równania energii do pomp odśrodkowych jest podstawową zasadą dynamiki płynów i inżynierii. W tym scenariuszu równanie energii jest używane do obliczenia natężenia przepływu pompy odśrodkowej, która odpowiada za przenoszenie wody między dwoma zbiornikami na różnych wysokościach. Pompa dostarcza energię równą 7500 dżuli na sekundę, a różnica wysokości między dolnym i górnym zbiornikiem wynosi 10 metrów. Dodatkowo, strata ciśnienia spowodowana tarciem i innymi oporami wynosi 5 metrów. Te parametry są kluczowe do rozwiązania natężenia przepływu za pomocą równania energii.

Ponieważ oba zbiorniki są otwarte na atmosferę, ciśnienie zarówno na wlocie, jak i na wylocie pompy jest równe ciśnieniu atmosferycznemu. Pozwala to na zniesienie się członów ciśnienia w równaniu energii. Ponadto, ponieważ prędkości na wlocie i wylocie są pomijalne, człony prędkości w równaniu również zostają usunięte. Równanie energii w tym przypadku zależy jedynie od wysokości grawitacyjnej i wysokości pompy.

Wysokość podnoszenia generowana przez pompę jest określana przez podzielenie mocy na wale przez iloczyn natężenia przepływu i ciężaru właściwego wody. Podstawienie tej wysokości podnoszenia do równania energii pozwala na obliczenie natężenia przepływu pompy

Zastosowanie równania energii

Jeśli natężenie przepływu pompy odśrodkowej, która wywiera ciśnienie 7500 dżuli na sekundę w celu podniesienia wody ze zbiornika o niższym poziomie do zbiornika o ...

Education

JoVE Core

Civil Engineering

Inżynieria lądowa

Unit 1

Jednostka 1

Finite Control Volume Analysis

Analiza skończonej objętości kontrolnej

KEY TERMS AND CONCEPTS

KLUCZOWE TERMINY I POJĘCIA

Application of the Energy Equation

centrifugal pump flow rate calculation

Centrifugal pump flow rate can be calculated with the energy equation. In this problem, water moves between two reservoirs at different elevations, and the pump provides the energy needed for the transfer. The pump input is 7500 joules per second, the elevation difference is 10 meters, and the head loss from friction and other resistances is 5 meters.

Both reservoirs are open to the atmosphere, so the pressure at the inlet and outlet is the same. That means the pressure terms in the energy equation cancel. The flow at the inlet and outlet is also negligible, so the velocity terms drop out as well.

With pressure and velocity terms removed, the equation depends on the gravitational head and the pump head. The pump head is found by dividing the net shaft power input by the product of the flow rate and the specific weight of water. Substituting that head into the energy equation makes it possible to solve for the pump flow rate.

Centrifugal Pump Flow Rate Calculation

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Wind Turbine Torque and Angular Momentum

The moment-of-momentum equation helps explain how wind turbine blades create torque. Torque is the turning effect of a force around an axis. In rotating systems, this equation links the motion of the wind with the force acting on it. The equation begins with Newton's second law for a fluid particle. That law says the rate of change of linear momentum equals the external force on the particle. To find torque, the position of the particle relative to the rotation axis is combined with that force.

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Turbine Work from Energy Changes

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application of the energy equation

Centrifugal pump flow rate can be calculated with the energy equation. In this problem, water moves between two reservoirs at different elevations, and the pump provides the energy needed for the transfer. The pump input is 7500 joules per second, the elevation difference is 10 meters, and the head loss from friction and other resistances is 5 meters. Both reservoirs are open to the atmosphere, so the pressure at the inlet and outlet is the same. That means the pressure terms in the energy...

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key terms and concepts

Use the energy equation to find the flow rate of a centrifugal pump lifting water between reservoirs. Includes elevation change, head loss, and pump head.

Centrifugal Pump Flow Rate Calculation | 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

Centrifugal Pump Flow Rate Calculation

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