What Is the Leidenfrost Effect?

Leidenfrost Phenomenon refers to the phenomenon that a liquid does not wet a hot surface, but only forms a vapor layer on it. It was discovered by scientist Leiden Frost in 1756.

Leidenfrost effect

Drop the water on the hot iron plate. If the temperature of the iron plate is only higher than the boiling point of water (100 ° C), the water will hiss and boil quickly. But when the iron plate reaches the Leidenfrost point, water will produce the Leidenfrost phenomenon. Water droplets will roll around the iron plate and slowly and gradually evaporate. Instead, the water droplets can last longer.

Under the Leidenfrost phenomenon, the part of the water droplets that is in contact with the iron plate will quickly boil to form water vapor. At the same time, the water droplets remain in a liquid state.

Leiden-Frost characterizes

In 2014, the Ice Bucket Challenge campaign to focus on ALS was swept the world, attracting many celebrities from all over the world. Watching

Konovalov accepts the challenge

In the video, the challenger was poured down with buckets of ice water, even as a bystander, he could feel the kind of chill. However, this challenge seems to be a "pediatrics" for Russian residents who live in cold regions all year round. Recently, a scientist from the "combat nation" carried out an upgraded version of the "Ice Bucket Challenge"-"liquid Nitrogen Challenge. " ^[2]

Anton Konovalov, 34, of Krasnoyarsk, works in a chemical plant that produces liquid nitrogen. In a video he uploaded recently, he poured it down with a bucket of liquid nitrogen, and the temperature of this liquid reached minus 195 degrees.

In order to verify the authenticity of the liquid in the bucket, Konovalov also stuck a branch into the bucket. It can be seen that the branch was immediately frozen and easily placed on him.

Konovalov accepts the challenge

His hands were crushed into pieces.

However, after being poured by such a cold liquid, Konovalov just shook his head. Although it was cold, it was intact. To make sure he was safe and sound, his friends came forward and touched his cheek. You can see that Konovalov's skin was still soft, but the latter laughed at the camera. ^[2]