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文献1中提到
By the
year 1919, the published methods for preventing bumping included
the addition of chips or bits of glass beads, porcelain plates,
bricks, granite, coal, talc, and pumice. One author noted that
powdered coal was very effective, while solid chunks were
valueless. Another author claimed the exact reverse. Not one author
“measured” bumping; it was “observed” only.
If a
liquid is pure and its container is clean, considerable
superheating is possible as discussed earlier. Under these
conditions boiling could occur in a cyclic manner: first a quiet,
non-boiling period as the liquid superheats; then an explosion when
the nucleation rate becomes large; and finally a sudden drop in the
liquid temperature after the superheat has disappeared as heat of
vaporization. The process would then repeat. If this view is
correct, cleanliness and purity are necessary for bumping. Addition
of most impurities would catalyze nucleation and decrease
bumping.
Glaser's
observations, that superheat (of particular liquids) is destroyed
by particles of high energy radiation, are pertinent to bumping.
Glaser calculated that hard cosmic ray particles struck his small
laboratory apparatus at a rate of about one per half-hour. This
would mean that a large-scale industrial boiler would be struck by
cosmic particles continuously. Thus nucleation should be
continuous, and bumping should be absent in industrial equipment.
Of course an alternate explanation for the lack of bumping in large
equipment is the great difficulty in obtaining sufficient purity
and cleanliness.
Before
bumping can be studied, it must be measured. A suggested method has
been tried at the University of Illinois. Bumping in a flask
creates sudden pressure fluctuations. These are used to vibrate a
flexible diaphragm. An electrical scheme is used to measure the
amplitude and frequency of the resulting deflections. Preliminary
measurements with methyl alcohol show quantitatively that a
decrease in pressure increases the severity of bumps, use of a
smooth glass surface causes stronger bumps than an etched glass
surface, and emanations from radium do not affect the course of
bumping. The first two observations are consistent with nucleation
theory. The later observation may mean that methyl alcohol does not
ionize readily. Additional quantitative tests are needed.

酒精灯加热
液体发生暴沸
随后
有个较长的平静期
接着是第二次暴沸
剧烈程度超过第一次
然后持续沸腾
直至烧干
这和自来水的顺序相反
自来水是先持续沸腾
后期出现爆沸
我没想明白
沸腾球持续沸腾时的凝结核
究竟是什么

撤去酒精灯后
停止沸腾
液面上飘着一颗液滴
这种现象也经常在水面出现

左侧玻璃球下方
突然出现一个气泡
迅速膨胀
并将右侧玻璃球内液体吹开

第一次暴沸的余波还未平息
就发生了第二次暴沸
我只观察到一次

将沸腾球竖直放置
也会出现暴沸
第二次比第一次剧烈

这是常见的摆放方式
加热单侧玻璃球
液体发生流动
无法实现暴沸
双侧同时加热
或许可以

打火机在左侧加热
液体却向左侧移动
有些奇怪
有兴趣的读者,可以参阅如下文献,进行深入了解
1:Westwater J W. Boiling of
liquids[M]//Advances in Chemical Engineering. Academic Press, 1956,
1: 1-76.
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