Name: forces in a 180° pipe bend
Uploaded: 2025-02-13T15:43:22.000Z
Duration: 1 min 15 s
Channel: JoVE

Water is flowing through a horizontal, U-shaped pipe bend. The cross-sectional area of the flow is 0.01 square meters, and the magnitude of the flow velocity is 15 meters per second throughout the bend.
The pressure at the entrance is 0.2 Megapascals, and the pressure at the exit is 0.16 Megapascals.
The objective is to find the components&#160;of the anchoring force along the x and y directions required to secure the bend in place.
Here, at the entrance and exit, the flow is in the y direction alone, indicating that the magnitude along the x direction reduces to zero.
The magnitude of the component force in the y direction can be obtained by simplifying the expression of the control volume.
The y-component of velocity is positive at the inflow and negative at the outflow, while the mass flow rate is negative at the inflow and positive at the outflow. According to the continuity equation, the mass flow can be considered constant.
With the expression of mass flow, the component of force in the y direction can be obtained.

application of the linear momentum equation

The application of the linear momentum equation can be used to analyze the forces needed to hold a 180-degree pipe bend in place with flowing water. In this case, water flows through the bend with a constant cross-sectional area of 0.01 square meters and a flow velocity of 15 meters per second. The pressure at the entrance is 0.2 Megapascals and the pressure at the exit is 0.16 Megapascals.
The goal is to determine the force components in the x and y directions to hold the pipe in place. Since the flow is only in the y direction at both the entrance and exit, the force in the x direction is zero. The force component in the y-direction can be calculated by considering the flow behavior across the control volume. The velocity in the y direction is positive at the inflow and negative at the outflow, while the mass flow rate remains constant throughout the bend according to the continuity equation.
By using the mass flow rate and applying the linear momentum equation, the y-component of the anchoring force can be found. This process allows for a clear analysis of the forces acting on the pipe bend due to the flow of water.

Application of the Linear Momentum Equation

Water is flowing through a horizontal, U-shaped pipe bend. The cross-sectional area of the flow is 0.01 square meters, and the magnitude of the flow ...

application-of-the-linear-momentum-equation

Education

JoVE Core

Civil Engineering

Unit 1

Finite Control Volume Analysis

KEY TERMS AND CONCEPTS

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. That means the x-direction force is zero. The y-direction force is found by looking at the flow across the control volume, which is the region being analyzed.

The velocity in the y direction is positive at the inflow and negative at the outflow. The mass flow rate stays constant through the bend according to the continuity equation, which means mass entering equals mass leaving. Using the mass flow rate and the linear momentum equation makes it possible to calculate the anchoring force in the y direction. This gives a clear way to analyze the forces on the pipe bend caused by the water flow.

Forces in a 180° Pipe Bend

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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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key terms and concepts

Use the linear momentum equation to find the x and y force components that hold a 180-degree pipe bend in place as water flows through it.

Forces in a 180° Pipe Bend | 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.

Forces in a 180° Pipe Bend

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