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

إذا كان لا بد من حساب معدل تدفق مضخة الطرد المركزي التي تطبق ضغطا قدره 7500 جول في الثانية لرفع المياه من خزان عند مستوى أدنى إلى خزان عند مستوى أعلى ، فيمكن استخدام معادلة الطاقة.
فرق المستوى بين الخزانات 10 أمتار ، وفقدان الرأس 5 أمتار.
نظرا لأن أسطح كلا الخزانين مفتوحة على الغلاف الجوي ، فإن الضغط والسرعة في كل من المدخل والمخرج يساويان صفرا ، مما يزيد من تبسيط معادلة الطاقة.
هنا ، يتم الحصول على رأس المضخة من خلال حاصل حاصل مدخلات طاقة العمود الصافي وحاصل ضرب وحدة وزن الماء ومعدل التدفق.
إذا تم استبدال رأس المضخة بمعادلة الطاقة المبسطة ، فيمكن الحصول على معدل تدفق المضخة.
علاوة على ذلك ، فإن استبدال القيم الواردة في التعبير بمعدل التدفق يعطي القيمة النهائية التي تشير إلى معدل ضخ المياه.

تطبيق معادلة الطاقة.

<div style="direction:rtl">يعتبر تطبيق معادلة الطاقة على المضخات الطاردة المركزية مبدأً أساسيًا في ديناميكيات وهندسة الموائع. في هذا السيناريو، تُستخدم معادلة الطاقة لحساب معدل تدفق مضخة طرد مركزي مسؤولة عن نقل المياه بين خزانين على ارتفاعات مختلفة. تولد المضخة مقدار من الطاقة يبلغ 7500 جول في الثانية، والفرق الرأسي بين الخزانين السفلي والعلوي هو 10 أمتار. بالإضافة إلى ذلك، فإن الفاقد في الضغط بسبب قوى الاحتكاك والقوى الأخرى هو 5 أمتار. هذه المعطيات ضرورية لحل معدل التدفق باستخدام معادلة الطاقة. نظرًا لأن كلا الخزانين مفتوحان للغلاف الجوي، فإن قيمة الضغط عند سحب وطرد المضخة تساوي الضغط الجوي. هذا التساوي يسمح لمصطلحات الضغط في معادلة الطاقة بالإلغاء. وعلاوة على ذلك، نظرًا لأن السرعات عند السحب والطرد لا تذكر، فإن مصطلحات السرعة في المعادلة يتم حذفها أيضًا. تعتمد معادلة الطاقة لهذه الحالة المحددة فقط على ضغط الجاذبية الرأسي وضغط المضخة. يتم تحديد الضغط الناتج عن المضخة عن طريق قسمة مقدار القدرة الصافية لعمود المضخة على حاصل ضرب معدل التدفق والوزن النوعي للمياه. يمكن تحديد الضغط الناتج عن المضخة عن طريق استبدال هذا الضغط في معادلة الطاقة واستنباط معدل تدفق المضخة.</div>

إذا كان معدل تدفق مضخة الطرد المركزي التي تطبق ضغطا قدره 7500 جول في الثانية لرفع المياه من خزان عند مستوى أقل إلى خزان عند ...

Education

JoVE Core

Civil Engineering

الهندسة المدنية

Unit 1

الوحدة الأولى

Finite Control Volume Analysis

تحليل حجم التحكم المحدود

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الأساسية

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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Continuity and Velocity in Pipe Flow

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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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