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

Если необходимо рассчитать расход центробежного насоса, который подает давление 7500 джоулей в секунду для подъема воды из резервуара на более низком уровне в резервуар на верхнем уровне, можно использовать уравнение энергии.
Перепад высот между водоемами составляет 10 метров, а потеря напора – 5 метров.
Поскольку поверхности обоих резервуаров открыты для атмосферы, давление и скорость как на входе, так и на выходе равны нулю, что еще больше упрощает уравнение энергии.
В этом случае напор насоса получается как отношение полезной мощности вала и произведение удельного веса воды на расход.
Если заменить напор насоса на упрощенное уравнение энергии, то можно получить расход насоса.
Кроме того, подстановка значений, указанных в выражении для расхода, дает окончательное значение, указывающее на скорость, с которой перекачивается вода.

Применение уравнения энергии

Применение уравнения энергии к центробежным насосам - фундаментальный принцип в гидродинамике и машиностроении. В этом сценарии уравнение энергии используется для расчета расхода центробежного насоса, отвечающего за перемещение воды между двумя резервуарами на разных высотах. Насос использует входную энергию 7500 джоулей в секунду, а разница по вертикали между нижним и верхним резервуарами составляет 10 метров. Кроме того, потеря напора из-за трения и других взаимодействий составляет 5 метров. Эти параметры необходимы для нахождения расхода с помощью уравнения энергии.

 Поскольку оба резервуара открыты для атмосферы, давление как на входе, так и на выходе насоса равно атмосферному давлению. Это позволяет исключить члены давления в уравнении энергии. Кроме того, поскольку скорости на входе и выходе пренебрежимо малы, члены скорости в уравнении также исключаются. Уравнение энергии для этого конкретного случая зависит только от гравитационного напора и напора насоса.

 Напор, создаваемый насосом, определяется путем деления чистой мощности на валу на произведение расхода и удельного веса воды. Подставляя этот напор в уравнение энергии и решая для расхода насоса, можно определить значение расхода.

Если расход центробежного насоса, который подает давление 7500 джоулей в секунду для подъема воды из резервуара на более низком уровне в резервуар на ...

Education

JoVE Core

Civil Engineering

Unit 1

Раздел 1

Finite Control Volume Analysis

Анализ методом конечных контрольных объемов

KEY TERMS AND CONCEPTS

ОСНОВНЫЕ ТЕРМИНЫ И ПОНЯТИЯ

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.

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civil engineering

Centrifugal Pump Flow Rate Calculation

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