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

L'acqua scorre attraverso una curva orizzontale del tubo a forma di U. L'area della sezione trasversale del flusso è di 0,01 metri quadrati e l'entità della velocità del flusso è di 15 metri al secondo in tutta la curva.
La pressione all'ingresso è di 0,2 Megapascal e la pressione all'uscita è di 0,16 Megapascal.
L'obiettivo è trovare i componenti della forza di ancoraggio lungo le direzioni x e y necessarie per fissare la curva in posizione.
Qui, all'ingresso e all'uscita, il flusso è nella sola direzione y, indicando che la magnitudine lungo la direzione x si riduce a zero.
L'entità della forza componente nella direzione y può essere ottenuta semplificando l'espressione del volume di controllo.
La componente y della velocità è positiva in entrata e negativa in uscita, mentre la portata massica è negativa in entrata e positiva in uscita. Secondo l'equazione di continuità, il flusso di massa può essere considerato costante.
Con l'espressione del flusso di massa, si può ottenere la componente della forza nella direzione y.

applicazione dell'equazione del momento lineare

L'applicazione dell'equazione del momento lineare, può essere utilizzata per analizzare le forze necessarie per mantenere in posizione una curva a 180 gradi, di tubo con acqua corrente. In questo caso, l'acqua scorre attraverso la curva con un'area trasversale costante di 0,01 metri quadrati e una velocità di flusso di 15 metri al secondo. La pressione all'ingresso è di 0,2 Megapascal e la pressione all'uscita è di 0,16 Megapascal.

L'obiettivo è determinare le componenti di forza nelle direzioni x e y, per mantenere in posizione il tubo. Poiché il flusso è solo nella direzione y, sia all'ingresso che all'uscita, la forza nella direzione x è zero. La componente di forza nella direzione y, può essere calcolata considerando il comportamento del flusso attraverso il volume di controllo. La velocità nella direzione y è positiva all'afflusso e negativa al deflusso, mentre la portata di massa rimane costante lungo tutta la curva secondo l'equazione di continuità.

Utilizzando la portata di massa e applicando l'equazione del momento lineare, è possibile trovare la componente y della forza di ancoraggio. Questo processo consente un'analisi chiara delle forze che agiscono sulla curva del tubo a causa del flusso d'acqua.

Applicazione dell'Equazione del Momento Lineare

L'acqua scorre attraverso una curva orizzontale del tubo a forma di U. L'area della sezione trasversale del flusso è di 0,01 metri quadrati e l'entità del flusso ...

application-of-the-linear-momentum-equation

Education

Didattica

JoVE Core

Civil Engineering

Ingegneria Civile

Unit 1

Unità 1

Finite Control Volume Analysis

Analisi a volume di controllo finito

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

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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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.

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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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