那个叫升力，不叫浮力

不知道升力英语怎么说



【 在 williamtong 的大作中提到: 】
: 飞机机翼的上下压力差也是浮力吗？
:
: 发自「今日水木 on Dol Guldor Express」
--
FROM 180.98.89.*

对了，阿基米德浮力定律的表述为什么不修改一下？

那个表述太有误导性了。本来是被排开的物体的体积乘以液体的密度，它表述成被排开的液体体积乘以液体的密度



【 在 williamtong 的大作中提到: 】
: lift
: 我一直觉得机翼上下压力差难以形成真正的升力，因为上边流速快也就快了一点点，假设飞机按0.8M速度前进，下边流过的是0.8M气流，上边是多少？估计0.801M，这么小的差别不可能托起几十吨的飞机
: 可以做个风洞实验，让0.8M气流吹过上下表面，看单位面积机翼产生的载荷，能否达到设计值
: ...................
--
FROM 180.98.89.*

撇开大气压，上边水的压力为0



【 在 Tschuess 的大作中提到: 】
: 如果一艘小船漂在水面上，上边压力怎么算？是0吗？
:
--
FROM 49.73.254.*

No One Can Explain Why Planes Stay in the Air

Do recent explanations solve the mysteries of aerodynamic lift?

BY ED REGIS


February 2020 Issue
The Sciences

In December 2003, to commemorate the 100th anniversary of the first flight of the Wright brothers, the New York Times ran a story entitled “Staying Aloft; What Does Keep Them Up There?” The point of the piece was a simple question: What keeps planes in the air? To answer it, the Times turned to John D. Anderson, Jr., curator of aerodynamics at the National Air and Space Museum and author of several textbooks in the field.

What Anderson said, however, is that there is actually no agreement on what generates the aerodynamic force known as lift. “There is no simple one-liner answer to this,” he told the Times. People give different answers to the question, some with “religious fervor.” More than 15 years after that pronouncement, there are still different accounts of what generates lift, each with its own substantial rank of zealous defenders. At this point in the history of flight, this situation is slightly puzzling. After all, the natural processes of evolution, working mindlessly, at random and without any understanding of physics, solved the mechanical problem of aerodynamic lift for soaring birds eons ago. Why should it be so hard for scientists to explain what keeps birds, and airliners, up in the air?


【 在 pkucannot 的大作中提到: 】
: 风阻这个东西就是物体表面有一层边界层，边界层很薄，外面是势流体。如果这个理论有问题，或者哪些现象解释不了，可以指出来。其他类比没道理的。
: 发自「今日水木 on iPhone 13」
--
FROM 49.93.79.*