Name: finding force on a curved plate in water
Uploaded: 2023-09-22T11:49:33.000Z
Duration: 1 min 12 s
Channel: JoVE

当曲面平板浸没时，垂直作用于平板的压力在大小和方向上均持续变化。
确定合力及其作用位置的一种方法是计算力的水平分量和垂直分量。
为此，使用二维等效载荷来表示作用在板上的分布载荷。
由水块重量产生的力的大小通过该水块的形心作用。
此外，水在方块的垂直面和水平面上也会产生压力分布。
沿垂直边，该力的大小等于梯形的面积，且此力作用于梯形的形心处。
沿水平边分布的力是恒定的，其大小等于矩形的面积。该力作用在矩形的形心上。
将这三个力相加可得到合力。通过应用力矩原理可确定压强中心的位置。

等宽曲面板上的流体压力

Fluid Pressure over Curved Plate of Constant Width

当一个曲面宽度恒定的板浸没在液体中时，垂直于板的压力的大小和方向都在持续发生变化。对于在这种情况下的某一点，计算合力的大小和位置通常是具有挑战性的。确定合力及其位置的方法之一是分别计算合力的水平分量和垂直分量。通过将板上的分布载荷转化为等效载荷的二维表示形式，可以对这个复杂的计算过程进行简化。 该方法的第一步是计算块内所含液体的重量。由于水的重量而产生出力的大小由比重、板厚度和块面积的乘积所得到的。这个力能够通过块的质心来发挥作用。此外，当水沿着物块作用在垂直方向和水平方向上的侧面则会使其产生压力分布。垂直方向的压力分布为梯形，同时水平方向上的压力分布为矩形。 位于垂直侧作用力的大小等于梯形的面积，并通过梯形的质心来发挥作用。与此同时，水平侧的作用力是恒定的，力的大小等于矩形的面积，同时也可以通过矩形的质心或水平侧的中心来产生作用。 将所有三个物块上的力进行相加后，可以得出作用在曲面上的净合力。此外，通过应用力矩原理，能够确定作用在曲面上的力位于液体压力中心的位置。虽然这种方法可能看似复杂，但有必要为了确保在各种工程应用中能够准确的来计算板上的力。

当一块宽度恒定的曲板浸入液体中时，垂直作用于板面的压力在大小和方向上均连续变化……

fluid-pressure-over-curved-plate-of-constant-width

Education

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JoVE Core

Mechanical Engineering

机械工程

Unit 1

第一单元

Center of Gravity and Centroid

重心与形心

KEY TERMS AND CONCEPTS

关键术语与概念

finding force on a curved plate in water

Fluid pressure on a curved plate of constant width changes in both size and direction. That makes the total force hard to find directly. A common method is to split the force into horizontal and vertical parts and then combine them.

The calculation becomes simpler by replacing the distributed load with an equivalent two-dimensional loading. The first step is to include the weight of the liquid inside the block. That force equals the specific weight of the liquid times the plate thickness and the block area. It acts through the centroid of the block.

Next, the water pressure on the block sides is found. The pressure on the vertical side forms a trapezoidal distribution. Its force equals the area of the trapezoid and acts through the trapezoid centroid. The pressure on the horizontal side is rectangular and constant. Its force equals the area of the rectangle and can act through the rectangle centroid or midpoint of its horizontal side.

After these three forces are added, the net resultant force on the curved plate is known. The center of pressure, which is the point where the liquid force acts, is then found using the principle of moments. This method can seem complex, but it gives an accurate force calculation for many engineering applications.

Finding Force on a Curved Plate in Water

center of gravity

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fluid pressure over curved plate of constant width

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key terms and concepts

Learn how to find the resultant fluid force on a curved plate by splitting it into horizontal and vertical parts, then locating the center of pressure.

Finding Force on a Curved Plate in Water | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

mechanical engineering

Finding Force on a Curved Plate in Water

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