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

A água está fluindo através de uma curva horizontal em forma de U. A área da seção transversal do fluxo é de 0,01 metros quadrados e a magnitude da velocidade do fluxo é de 15 metros por segundo ao longo da curva.
A pressão na entrada é de 0,2 Megapascals e a pressão na saída é de 0,16 Megapascals.
O objetivo é encontrar os componentes da força de ancoragem ao longo das direções x e y necessárias para fixar a dobra no lugar.
Aqui, na entrada e na saída, o fluxo está apenas na direção y, indicando que a magnitude ao longo da direção x se reduz a zero.
A magnitude da força do componente na direção y pode ser obtida simplificando a expressão do volume de controle.
O componente y da velocidade é positivo na entrada e negativo na saída, enquanto a taxa de fluxo de massa é negativa na entrada e positiva na saída. De acordo com a equação de continuidade, o fluxo de massa pode ser considerado constante.
Com a expressão do fluxo de massa, o componente de força na direção y pode ser obtido.

aplicação da equação de momento linear

A aplicação da equação de momento linear pode ser usada para analisar as forças necessárias para manter uma curva de tubo de 180 graus no lugar com água fluindo. Neste caso, a água flui através da curva com uma área transversal constante de 0,01 metros quadrados e uma velocidade de fluxo de 15 metros por segundo. A pressão na entrada é de 0,2 Megapascals e a pressão na saída é de 0,16 Megapascals.

O objetivo é determinar os componentes de força nas direções x e y para manter o tubo no lugar. Como o fluxo está apenas na direção y na entrada e na saída, a força na direção x é zero. O componente de força na direção y pode ser calculado considerando o comportamento do fluxo através do volume de controle. A velocidade na direção y é positiva na entrada e negativa na saída, enquanto a taxa de fluxo de massa permanece constante ao longo da curva de acordo com a equação de continuidade.

Usando a taxa de fluxo de massa e aplicando a equação de momento linear, o componente y da força de ancoragem pode ser encontrado. Este processo permite uma análise clara das forças que atuam na curva do tubo devido ao fluxo de água.

Aplicação da equação de momento linear

A água está fluindo através de uma curva horizontal em forma de U. A área da seção transversal do fluxo é de 0,01 metros quadrados, e a magnitude do fluxo ...

application-of-the-linear-momentum-equation

Education

JoVE Core

Civil Engineering

Engenharia Civil

Unit 1

Unidade 1

Finite Control Volume Analysis

Análise de Volume de Controle Finito

KEY TERMS AND CONCEPTS

TERMOS E CONCEITOS-CHAVE

Application of the Linear Momentum Equation

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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conservation of mass in fixed, nondeforming control volume

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Continuity and Velocity in Pipe Flow

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conservation of mass in moving, nondeforming control volume

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Stormwater Detention Basin Mass Balance

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linear momentum in control volume

Momentum Balance for Fluid Control Volumes

Linear momentum balance for a fluid control volume links Newton’s second law to moving fluid. The law says that the rate of change of linear momentum equals the sum of the external forces acting on the system. In a fluid system, this idea helps explain how motion and force are related. A control volume can match the fluid system at a specific moment. When that happens, the forces on the control volume and the system are the same. Reynolds transport theorem explains this connection by splitting...

application of the linear momentum equation

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.

moment-of-momentum equation

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.

conservation of energy in control volume

Turbine Work from Energy Changes

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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...

design example: forces in sluice gate

Sluice Gate Water Pressure and Reaction Force

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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 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

Forces in a 180° Pipe Bend

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