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Finite Control Volume Analysis

Forces in a 180° Pipe Bend

Description

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.

Transcript

水正流经一个水平的U形弯管。流动的横截面积为0.01平方米,且在整个弯管中流速大小为15米每秒。

入口处的压力为 0.2 兆帕,出口处的压力为 0.16 兆帕。

目标是求出为固定弯管所需沿 xy 方向的锚固力分量 。

此处,在入口和出口处,流动仅沿 y 方向,表明沿该方向的分量大小 x 方向减小至零。

通过简化控制体的表达式,可得到 y 方向上分力的大小。

速度的 y 分量在入口处为正值,在出口处为负值,而质量流量在入口处为负值,在出口处为正值。根据连续性方程,质量流量可视为恒定。

根据质量流量的表达式,可求...