Bilingual edition: English is preserved and Chinese follows each unit. Terminology uses the confirmed v20260916 glossary; automated semantic review remains traceable.
中英双语版：英文原文完整保留，中文紧随对应单元；术语采用 v20260916 确认表，自动语义审校结果可追溯。

Wall Tension

壁张力

Pascal's principle requires that the pressure is everywhere the same inside the balloon at equilibrium. But examination immediately reveals that there are great differences in wall tension on different parts of the balloon. The variation is described by Laplace's Law.

Once you have established the geometry of the balloon, then the tension, pressure and radius have a definite relationship and could be used to measure tension or pressure. That is, if you have a gauge to measure pressure, then you can calculate the wall tension. In the interesting experiment of putting one end of a balloon into liquid nitrogen, you can collapse one end of it by cooling while the other end stays essentially at its previous radius. This can be taken to imply that the pressure is not diminishing significantly since for a given tension, the pressure is related to the radius.

一旦你确定了气球的几何形状，那么张力、压力和半径之间就存在确定的关系，可以用来测量张力或压力。也就是说，如果你有一个测量压力的仪器，就可以计算出壁张力。在有趣的实验中，将气球的一端放入液氮中，可以冷却使一端塌陷，而另一端则基本保持原来的半径。这可以说明压力并没有显著降低，因为对于给定的张力，压力与半径有关。
帕斯卡原理要求在平衡状态下气球内部的压力处处相等。但立即检查就会发现，气球不同部位的壁张力存在显著差异。这种差异由拉普拉斯定律描述。
 Index

Laplace's law concepts
拉普拉斯定律概念
 
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Laplace's Law

拉普拉斯定律

The larger the vessel radius, the larger the wall tension required to withstand a given internal fluid pressure.

容器半径越大，为承受给定的内部流体压力所需的壁面张力就越大。

For a given vessel radius and internal pressure, a spherical vessel will have half the wall tension of a cylindrical vessel.

对于给定的容器半径和内部压力，球形容器的壁张力是圆柱形容器的一半。

Why does the wall tension increase with radius?

为什么壁张力随着半径增加而增加？
 		Index

Laplace's law concepts

Balloon example
索引拉普拉斯定律概念气球例子
 
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Why does wall tension increase with radius?

为什么壁张力随着半径增加而增加？

If the upward part of the fluid pressure remains the same, then the downward component of the wall tension must remain the same. But if the curvature is less, then the total tension must be greater in order to get that same downward component of tension. For equilibrium of a load hanging on a cable, you can explore the effects of having a smaller angle for the supporting cable tension.
如果流体的向上部分压力保持不变，那么壁张力的向下分量也必须保持不变。但如果曲率减小，为了得到相同的向下分量张力，总张力必须更大。对于悬挂负载的缆索，可以探讨支撑缆索张力在角度更小时的影响。
 Index

Laplace's law concepts

Balloon example
索引拉普拉斯定律概念气球例子
 
HyperPhysics***** Mechanics ***** Fluids
HyperPhysics ***** 力学 ***** 流体
R Nave
 Go Back
返回