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

Si l’on doit calculer le débit d’une pompe centrifuge qui applique une pression de 7500 joules par seconde pour soulever l’eau d’un réservoir à un niveau inférieur à un réservoir à un niveau supérieur, l’équation de l’énergie peut être utilisée.
La différence de niveau entre les réservoirs est de 10 mètres et la perte de charge est de 5 mètres.
Comme les surfaces des deux réservoirs sont ouvertes à l’atmosphère, la pression et la vitesse à l’entrée et à la sortie sont nulles, ce qui simplifie encore l’équation énergétique.
Ici, la hauteur de refoulement de la pompe est obtenue par le quotient de la puissance nette de l’arbre absorbée et le produit du poids unitaire de l’eau et du débit.
Si la tête de la pompe est substituée à l'équation d'énergie simplifiée, le débit de la pompe peut être obtenu.
De plus, en substituant les valeurs fournies dans l’expression pour le débit, on obtient la valeur finale indiquant le débit auquel l’eau est pompée.

application de l'équation énergétique

L'application de l'équation énergétique aux pompes centrifuges est un principe fondamental de la dynamique des fluides et de l'ingénierie. Dans ce scénario, l'équation énergétique est utilisée pour calculer le débit d'une pompe centrifuge chargée de transférer l'eau entre deux réservoirs situés à des altitudes différentes. La pompe applique un apport d'énergie de 7 500 joules par seconde et la différence verticale entre les réservoirs inférieur et supérieur est de 10 mètres. De plus, la perte de charge due au frottement et aux autres résistances est de 5 mètres. Ces paramètres sont essentiels pour résoudre le débit à l'aide de l'équation énergétique.

Étant donné que les deux réservoirs sont ouverts à l'atmosphère, la pression à l'entrée et à la sortie de la pompe est égale à la pression atmosphérique. Cela permet aux termes de pression dans l'équation énergétique de s'annuler. De plus, comme les vitesses à l'entrée et à la sortie sont négligeables, les termes de vitesse dans l'équation sont également éliminés. L'équation énergétique pour ce cas spécifique ne dépend que de la charge gravitationnelle et de la charge de la pompe.

La hauteur manométrique générée par la pompe est déterminée en divisant la puissance nette de l'arbre par le produit du débit et du poids spécifique de l'eau. En remplaçant cette hauteur manométrique dans l'équation énergétique et en résolvant le problème du débit de la pompe, on peut déterminer ce dernier.

Application de l'équation énergétique

Si le débit d’une pompe centrifuge qui applique une pression de 7500 joules par seconde pour soulever l’eau d’un réservoir à un niveau inférieur à un réservoir à ...

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Finite Control Volume Analysis

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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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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

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Centrifugal Pump Flow Rate Calculation

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