Name: sluice gate water pressure and reaction force
Uploaded: 2025-02-13T15:43:22.000Z
Duration: 1 min 11 s
Channel: JoVE

بوابة السد هي حاجز رأسي يتحكم في تدفق المياه في القناة.
لحساب القوى المؤثرة على بوابة السد ، ضع في اعتبارك المياه المتدفقة تحت البوابة.
تعتمد القوى على أعماق مياه المنبع والمصب
على جانب المنبع ، يكون العمق z1 ، وعلى الجانب السفلي ، يكون العمق z2.
يخلق الاختلاف في الضغط بين الجانبين قوة صافية على البوابة.
باستخدام مبدأ برنولي ، يمكن حساب سرعة الماء تحت البوابة ، V2 ، بناء على فرق الضغط وانخفاض الارتفاع.
يتم حساب قوة التفاعل على البوابة من القوة الهيدروستاتيكية المؤثرة بسبب عمود الماء على كلا الجانبين.
تكون القوة أكبر عند إغلاق البوابة بسبب فرق الضغط الأكبر.
عندما يتم فتح البوابة ، تقل قوة التفاعل مع تدفق الماء بحرية تحت البوابة ، مما يقلل من صافي فرق الضغط الهيدروستاتيكي.
يسمح هذا المبدأ بتحديد قوة التثبيت المطلوبة للحفاظ على البوابة في مكانها أثناء التشغيل.

مثال التصميم: القوى المؤثرة على حواجز التصريف.

Design Example: Forces in Sluice Gate

<div style="direction:rtl">في الهندسة الهيدروليكية، تعد حواجز التصريف ضرورية لإدارة تدفق المياه المتدفقة نحو القنوات والخزانات وأنظمة الري. تعمل حواجز التصريف كبوابات رأسية، تنظم تدفق المياه عن طريق ضبط ارتفاع فتحة البوابة، مما يغير من سرعة وضغط المياه المتدفقة أسفل الحاجز. يعد فهم القوى مؤثرة أمرًا بالغ الأهمية عند تصميم حواجز التصريف التي يمكنها تحمل فروق الضغط الديناميكية، خاصة عندما تكون البوابة مغلقة أو مفتوحة بشكل جزئي. تتضمن المتغيرات الرئيسية في تحليل القوى المؤثرة على حاجز تصريف حيث عمق المدخل z1 وعمق المخرج z2. عندما تكون البوابة مغلقة، يكون عمق المياه أكبر على جانب المدخل، مما يخلق فرق ضغط كبير عبر البوابة. ينتج عن فرق الضغط هذا قوة صافية، تتطلب نظام تثبيت لإبقاء البوابة في مكانها بشكل آمن. يتناسب الضغط الهيدروستاتيكي المؤثر على جانب المدخل طرديا مع عمق المياه وقوة الجاذبية، بينما يعتمد الضغط عند المخرج على z2. يؤدي تدرج الضغط الناتج عبر البوابة إلى تكون قوة صافية تؤثر عكس اتجاه الضغط باتجاه جانب المخرج. عندما تكون بوابة السد مفتوحة جزئيًا، يتدفق الماء تحتها، ويمكن استخدام مبدأ برنولي لتحديد سرعة المياه عند المخرج ، V2. <img alt="Equation 1" src="/files/ftp_upload/18056/18056_Equation_1.svg" style="text-align: center; height: 90px;"> بمعلومية عمق المدخل والمخرج، يربط مبدأ برنولي بين التغير في الضغط بسبب الاختلافات في ارتفاع الماء، مما يسمح بحساب V2 بناءً على اختلافات الارتفاع وتدرجات الضغط. يقلل هذا التدفق من الضغط الواقع على البوابة من خلال السماح بالحركة بدلاً من التراكم، مما يقلل من القوة الصافية مع تدفق الماء بحرية. تتأثر قوة رد الفعل الكلية على حاجز التصريف بشكل أساسي بالقوة الهيدروستاتيكية الناتجة عن عمود الماء عند المدخل، والتي تكون في أعلى مستوياتها عندما تكون البوابة مغلقة تمامًا. عندما تفتح البوابة ويتدفق الماء تحتها، فإن الانخفاض في فرق الضغط يتسبب في تقليل قوة رد الفعل. <img alt="Equation 2" src="/files/ftp_upload/18056/18056_Equation_2.svg" style="text-align: center; height: 90px;"></div>

بوابة السد هي حاجز رأسي يتحكم في تدفق المياه في القناة.
لحساب القوى المؤثرة على بوابة السد ، ضع في اعتبارك المياه المتدفقة تحت ...

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

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 downstream side. In that case, the gate needs an anchoring system to keep it secure.

The pressure on the upstream side is hydrostatic pressure, which depends on water depth and gravity. The downstream pressure depends on z2. Together, these pressures create the pressure gradient that pushes on the gate.

When the sluice gate is partially open, water flows beneath it. Bernoulli's principle can then be used to find the downstream velocity, V2, from the upstream and downstream depths. As the water moves through the opening instead of building up, the pressure difference becomes smaller and the reaction force on the gate decreases. The total reaction force is therefore highest when the gate is fully closed and lower as the gate opens.

Sluice Gate Water Pressure and Reaction Force

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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.

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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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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 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

Learn how upstream and downstream water depths affect pressure, flow speed, and reaction force on a sluice gate when it is closed or partially open.

Sluice Gate Water Pressure and Reaction Force | 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

Sluice Gate Water Pressure and Reaction Force

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