[hamdani yusuf (OP)]

I just found old raw videos I took while discussing in this thread.
https://www.thenakedscientists.com/forum/index.php?topic=78517

I guess it's time to edit and upload them, so the information that they contain becomes available to more people.

[hamdani yusuf (OP)]

Here's my first video, not containing water yet, to demonstrate effects of high power microwave to conductors with different diameter and position.

The effect is similar to resistive heating.

[hamdani yusuf (OP)]

Here's another video showing how to produce superheated water.

Unfortunately it doesn't provide explanation.

[Bored chemist]

"How does microwave superheat water?"
The same way that anything else does.

[hamdani yusuf (OP)]

"How does microwave superheat water?"
The same way that anything else does.

Is it the same way as infrared stove?

[hamdani yusuf (OP)]

Here's another demonstration of superheated water explodes inside the microwave while being heated. The video was made by CrazyRussianHacker.

Preventing superheated water by microwave

[Bored chemist]

This isn't some weird magical phenomenon.
https://en.wikipedia.org/wiki/Bumping_(chemistry)

Is it the same way as infrared stove?

Do you know what

anything

means?

[hamdani yusuf (OP)]

This isn't some weird magical phenomenon.
https://en.wikipedia.org/wiki/Bumping_(chemistry)

Is it the same way as infrared stove?

Do you know what

anything

means?

Here's what wikipedia says.

Bumping occurs when a liquid is heated or has its pressure reduced very rapidly, typically in smooth, clean glassware. The hardest part of bubble formation is the formation of the small bubble; once a bubble has formed, it can grow quickly. Because the liquid is typically above its boiling point, when the liquid finally starts to boil, a large vapor bubble is formed that pushes the liquid out of the test tube, typically at high speed. This rapid expulsion of boiling liquid poses a serious hazard to others and oneself in the lab. Furthermore, if a liquid is boiled and cooled back down, the chance of bumping increases on each subsequent boil, because each heating cycle progressively de-gasses the liquid, reducing the number of remaining nucleation sites.

The problem is the description there doesn't match with my experiments. First,  the superheating can be done slowly. The boiling/desuperheating process can also be done slowly. 

[Eternal Student]

Hi.

Here's another demonstration of superheated water explodes inside the microwave while being heated.

    Please, please put some information in the text about the videos.
    For example, one of those videos seems to have been produced in Russia and seems to be a commercial business (the people who made the video may get paid per view by Google).   At the current time, a lot of sanctions have been put against Russia.   Even scientific endeavours that involved a collaboration (for example, the ExoMars mission carrying the Rosalind Franklin mars rover) have been put on indefinite hold.  It's not clear that a UK based forum website should be promoting those videos.
      However,  there's no rigorous restriction placed on the use of Russian resources that I know of at the moment.  It's just that I would always be grateful if someone using a video in their post can tell the audience something about it in the text - like the title, the creator or author and where the video is hosted (e.g. YouTube).   The users can make their own choice about whether they wish to follow that link.
- - - - - -
 
   These points about superheating in a microwave oven seem relevant.  I don't know, I'm not an expert on microwave ovens.

1.  Microwaves heat water rapidly.  There just isn't much time for bumping to happen or nucleation sites to form.   Other forms of heating, like putting a beaker of water into an oven fail to match this rate of heating.  There is much more time for the formation of a gas bubble, a nucleation site where further changes in phase can happen.

2.  Microwave ovens heat a small beaker of water quite evenly across the whole volume.  There isn't much of a convection current or turbulent flow in the fluid.  This also reduces the formation of nucleation sites.   The superheating effect is likely to be greatly reduced if a beam of microwaves was focused on only one corner of the beaker.

Best Wishes.

[hamdani yusuf (OP)]

For example, one of those videos seems to have been produced in Russia and seems to be a commercial business (the people who made the video may get paid per view by Google).   At the current time, a lot of sanctions have been put against Russia.   Even scientific endeavours that involved a collaboration (for example, the ExoMars mission carrying the Rosalind Franklin mars rover) have been put on indefinite hold.  It's not clear that a UK based forum website should be promoting those videos.

AFAIK, playing a Youtube video from a third party site isn't count as a view. I tested it with my own video.  CMIIW.
Anyway, I can just add information in the description that the video was made by a Russian. But keep in mind that most Russians have nothing to do with the invasion. They just want to live their lives peacefully.

[hamdani yusuf (OP)]

Microwaves heat water rapidly.  There just isn't much time for bumping to happen or nucleation sites to form.   Other forms of heating, like putting a beaker of water into an oven fail to match this rate of heating.  There is much more time for the formation of a gas bubble, a nucleation site where further changes in phase can happen.

As I said previously, rapidness doesn't seem to be the cause of superheating. It can be done slowly,  just like the desuperheating process, either by boiling using contact with conductive material, or just letting it slowly cool down to normal warm water.
The rapidness of heating depends on the quantity of water being heated, as well as the power of the microwave. The more water being heated, the slower the process becomes. But it can still be superheated.
In many cases, real world experiments can't be replaced by armchair thoughts, no matter how hard you think about it, especially when the underlying principle of the process is not widely understood, or there are some widespread misconceptions involved. That's why I made the investigation in the first place.

[Bored chemist]

especially when the underlying principle of the process is not widely understood,

You may not understand it. That does not mean it is not understood.

That's why I made the investigation in the first place.

Did your investigations lead you to the explanation of why the liquid does not boil?
https://en.wikipedia.org/wiki/Laplace_pressure

[hamdani yusuf (OP)]

I'm editing the next videos of my investigation on superheated water by microwave. If you are curious what they will show, just open the spoiler.

Spoiler: show

The first video shows my attempt to superheat my drinking water, which is a bottled mineral water. The result is that the water always boils and the intended superheating process can not occur.

The second video uses demineralized water.
But the microwave power is too much for the water, which makes it explode, so further investigation can't be done.

The third video shows the experiment in a more controlled manner.
It produces superheted water which can be desuperheated slowly.

[Eternal Student]

Hi.

AFAIK, playing a Youtube video from a third party site isn't count as a view. I tested it with my own video.  CMIIW.

I'm not a YouTube or Google expert.  I also don't know how the nakedscientists website is setup.
However, there are several articles suggesting that YT views from a 3rd party website do still get counted.

   Do Embedded YouTube Videos Add to the View Count?
The short answer is, yes.
The long answer is a little more complicated.....   

[Taken fromhttps://www.alliedpixel.com/2019/09/do-embedded-youtube-videos-add-to-the-view-count/  ]

The things they go on to explain as being "complicated" include (but are not limited to) the following:   It might be that you (Hamdani) didn't watch for long enough or have already watched that video many times... these things can stop YT counting another view.
    The "number of views" counter at the bottom of a YT video is also only an approximation.  It's impossible to keep that number correct and updated in real time over a distributed service provision.   Specifically, you can be served that video from many different servers.  Sometimes you can come back to a YT video and the no. of views has apparently gone down - this is purely a consequence of being served the video from some other server.   
    The record of the number of views is updated in a complicated way, so that it is only correct eventually and if all views are stopped for a while so that every server catches up and reports its changes.  This avoids halting every server while just one server was editing the value of the variable (which is what you would have to do if there was a single value used by all servers).  More significantly, if one server crashed before it returned the new amended value to the pool of servers then no other server could serve the video because they don't have a correct value of the no. of views they can call up.

Best Wishes.

[Eternal Student]

Hi again,

But keep in mind that most Russians have nothing to do with the invasion. They just want to live their lives peacefully.

   I'm well aware of that.  I'm saddened by the net effects of the current situation.  The situation with Russia was just one example of why it's helpful to have some text describing any video links.   I honestly don't know if we should stop watching Russian made YT videos at the moment, or if there's more good to come from continuing to co-operate and work with a common goal like developing science.  I just don't know - but the users should have the choice and should always be aware that some of those YT videos may be monetized.

  Anyway, I can see you've already done some editing on your earlier posts, thank you for that.

Best Wishes.

[hamdani yusuf (OP)]

You may not understand it. That does not mean it is not understood.

If you think you already understand it, you should be able to describe my experimental results correctly.

[hamdani yusuf (OP)]

Did your investigations lead you to the explanation of why the liquid does not boil?
https://en.wikipedia.org/wiki/Laplace_pressure

So far, no.

[Bored chemist]

you should be able to describe my experimental results correctly.

I wasn't aware that you had done any experiments.
What did you do?
What happened?

Is there anything that wasn't explained by the conventional explanation?

[hamdani yusuf (OP)]

you should be able to describe my experimental results correctly.

I wasn't aware that you had done any experiments.
What did you do?
What happened?

Is there anything that wasn't explained by the conventional explanation?

I haven't finished editing the videos. But I've provided a spoiler in case you have no patience to wait until tomorrow, or the day after tomorrow. It depends on my workload.

[hamdani yusuf (OP)]

This video contains valuable information regarding commonly used commercial microwave oven. Although he only talks about microwave for 8 minutes, after which he goes back to focus on high power laser beam, which is his core business.