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

毎秒7500ジュールの圧力を加えて、下位の貯水池から上位の貯水池に水を持ち上げる遠心ポンプの流量を計算する必要がある場合は、エネルギー方程式を使用できます。
貯水池間の水位差は10メートルで、落差は5メートルです。
両方の貯留層の表面が大気に開いているため、入口と出口の両方の圧力と速度はゼロになり、エネルギー方程式がさらに単純化されます。
ここで、ポンプの揚程は、純軸動力入力と水の単位重量と流量の積との商によって求められます。
ポンプのヘッドを簡略化されたエネルギー方程式に代入すると、ポンプの流量を取得できます。
さらに、式で提供される値を流量に代入すると、水が汲み上げられる速度を示す最終値が得られます。

エネルギー方程式の適用

遠心ポンプへのエネルギー方程式の適用は、流体力学と工学における基本原理です。このシナリオでは、エネルギー方程式を使用して、異なる標高にある 2 つの貯水池間で水を移動させる遠心ポンプの流量を計算します。ポンプは 1 秒あたり 7500 J のエネルギー入力を適用し、下部貯水池と上部貯水池の垂直差は 10 m です。さらに、摩擦やその他の抵抗による水頭損失は 5 m です。これらのパラメータは、エネルギー方程式を使用して流量を解くために不可欠です。

 両方の貯水池が大気に開放されているため、ポンプの入口と出口の両方の圧力は大気圧に等しくなります。これにより、エネルギー方程式の圧力項が相殺されます。さらに、入口と出口の速度は無視できるため、方程式の速度項も排除されます。この特定のケースのエネルギー方程式は、重力水頭とポンプ水頭のみに依存します。

 ポンプによって生成されるヘッドは、正味シャフト電源入力を流量と水の比重の積で割ることによって決定されます。このヘッドをエネルギー方程式に代入してポンプの流量を解くと、ポンプの流量を決定できます。

毎秒7500ジュールの圧力を加える遠心ポンプの流量が、より低いレベルの貯水池から貯水池に水を持ち上げる場合...

Education

JoVE Core

Civil Engineering

土木工学

Unit 1

ユニット1

Finite Control Volume Analysis

有限コントロールボリューム法による解析

KEY TERMS AND CONCEPTS

主要用語と概念

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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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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civil engineering

Centrifugal Pump Flow Rate Calculation

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