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

초당 7500줄의 압력을 가하여 낮은 수준의 저수지에서 상위 수준의 저수지로 물을 들어 올리는 원심 펌프의 유량을 계산해야 하는 경우 에너지 방정식을 사용할 수 있습니다.
저수지 사이의 레벨 차이는 10미터이고 수두 손실은 5미터입니다.
두 저장소의 표면이 대기에 개방되어 있기 때문에 입구와 출구 모두의 압력과 속도가 0이 되어 에너지 방정식을 더욱 단순화합니다.
여기서, 펌프의 수드는 네트 샤프트 동력 입력의 몫과 물의 단위 중량 및 유량의 곱에 의해 얻어집니다.
단순화된 에너지 방정식을 펌프의 수두로 대체하면 펌프의 유량을 얻을 수 있습니다.
또한, 유속에 대한 표현식에 제공된 값을 대체하면 물이 펌핑되는 속도를 나타내는 최종 값이 제공됩니다.

에너지 방정식의 적용

에너지 방정식을 원심 펌프에 적용하는 것은 유체 역학 및 엔지니어링의 기본 원리입니다. 이 시나리오에서 에너지 방정식은 서로 다른 고도에 있는 두 저수지 사이에 물을 전달하는 원심 펌프의 유량을 계산하는 데 사용됩니다. 펌프는 초당 7500줄의 에너지를 입력하며, 하부와 상부 저수지 사이의 수직 차이는 10미터입니다. 또한 마찰 및 기타 저항으로 인한 수두 손실은 5미터입니다. 이러한 매개변수는 에너지 방정식을 사용하여 유량을 푸는 데 필수적입니다.

두 저수지 모두 대기에 개방되어 있기 때문에 펌프의 입구와 출구의 압력은 모두 대기압과 같습니다. 이를 통해 에너지 방정식의 압력 항을 상쇄할 수 있습니다. 또한 입구와 출구의 속도가 무시할 수 있으므로 방정식의 속도 항도 제거됩니다. 이 특정 사례의 에너지 방정식은 중력 수두와 펌프 수두에만 의존합니다.

펌프에서 생성되는 수두는 순 샤프트 전력 입력을 유량과 물의 비중의 곱으로 나누어 결정됩니다. 이 수두를 에너지 방정식에 대입하고 펌프의 유량을 풀면 결정될 수 있습니다.

초당 7500줄의 압력을 가하여 낮은 수준의 저수지에서 저수지로 물을 들어 올리는 원심 펌프의 유량이 ...

Education

교육

JoVE Core

Civil Engineering

토목공학

Unit 1

제1단원

Finite Control Volume Analysis

유한 제어 체적 해석

KEY TERMS AND CONCEPTS

주요 용어 및 개념

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

conservation of mass in finite cotrol volume

conservation-of-mass-in-finite-cotrol-volume

Continuity Equation for a Fixed Control Volume

The continuity equation describes conservation of mass for a fixed control volume. In fluid mechanics, a system is a collection of the same contents over time, and its mass stays constant. That idea is the starting point for deriving the equation. To analyze flow, a fixed, non-deforming control volume is chosen so it matches the system at one instant. The Reynolds transport theorem then links the system to the control volume. It shows that the rate of change of system mass has two parts: mass...

conservation of mass in fixed, nondeforming control volume

conservation-of-mass-in-fixed-nondeforming-control-volume

Continuity and Velocity in Pipe Flow

Conservation of mass explains how fluid moves through a fixed control volume such as a pipe or duct. In a fixed, nondeforming control volume, the total mass stays constant unless mass enters or leaves through the control surfaces. For steady, incompressible flow, the mass entering the system equals the mass leaving it. A sewer pipe is a useful example of this idea. It can be treated as a fixed control volume with inlet and outlet control surfaces around the flow region. Because the fluid is...

conservation of mass in moving, nondeforming control volume

conservation-of-mass-in-moving-nondeforming-control-volume

Stormwater Detention Basin Mass Balance

Stormwater detention basins use mass balance to manage runoff during heavy rainfall. These basins are especially important in urban areas, where impervious surfaces can increase flooding risk. Engineers use the conservation of mass to track how water enters, is stored in, and leaves the basin. In a detention basin, the control volume is the water inside the basin. Its boundaries are the basin walls, the inflow pipes, and the outflow structures. During a rain event, water comes in through the...

linear momentum in control volume

Momentum Balance for Fluid Control Volumes

Linear momentum balance for a fluid control volume links Newton’s second law to moving fluid. The law says that the rate of change of linear momentum equals the sum of the external forces acting on the system. In a fluid system, this idea helps explain how motion and force are related. A control volume can match the fluid system at a specific moment. When that happens, the forces on the control volume and the system are the same. Reynolds transport theorem explains this connection by splitting...

application of the linear momentum equation

application-of-the-linear-momentum-equation

Forces in a 180° Pipe Bend

Forces in a 180-degree pipe bend can be found by applying the linear momentum equation to flowing water. The pipe has a constant cross-sectional area of 0.01 square meters, and the water moves at 15 meters per second. The pressure at the inlet is 0.2 megapascals, and the pressure at the outlet is 0.16 megapascals. The goal is to find the force components in the x and y directions that hold the bend in place. In this case, the flow is only in the y direction at both the entrance and the exit.

moment-of-momentum equation

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.

conservation of energy in control volume

Turbine Work from Energy Changes

A turbine can turn fluid energy into shaft work when flow passes through a control volume. The fluid enters the turbine at one point and leaves at another. Under steady-flow conditions, there is no energy buildup inside the control volume, so the stored energy does not change with time. This steady-flow setup makes the energy equation simpler. The turbine is treated as doing mechanical work, and heat transfer is taken as negligible, so Q̇ is approximately zero. The flow at the inlet and outlet...

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...

design example: forces in sluice gate

Sluice Gate Water Pressure and Reaction Force

Sluice gates control water flow in channels, reservoirs, and irrigation systems. They work as vertical barriers with an opening that can be raised or lowered. Changing the opening height changes the water velocity and pressure below the gate. The forces on a sluice gate depend on the water depths upstream and downstream, written as z1 and z2. When the gate is closed, the upstream water depth is greater. That creates a strong pressure difference across the gate and a net force toward the...

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 offers a foundational exploration of essential construction materials such as bricks, stones, steel, wood, and concrete, along with fluid mechanics topics like flow over immersed bodies, open channel flow, and dimensional modeling. It also covers key surveying concepts, including leveling, traverse adjustments, curve design, topographic mapping, and geospatial technologies (GPS & GIS). Science-in-action videos showcase laboratory research on materials, fluids, and surveying practices in real-world engineering systems.

civil engineering

Centrifugal Pump Flow Rate Calculation

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