Drum implosion vacuum pressure gravity work

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Drum implosion vacuum pressure gravity work
« on: July 09, 2023, 12:17:02 PM »
I was thinking through creating a vacuum in a drum by cooling steam, then the drum imploding.  Something carried out by Mythbusters.

Quote

How to Make a Train Tanker Implode | MythBusters





I was working through the argument, “does a vacuum draw in pressure?  Or does pressure flow in to vacuum?”

The answer is you need a difference in energy. The high pressure with more energy will equalize, or attempt to equalize with the lower pressure.  Flow from high pressure to low pressure.  From a higher energy state to a lower energy state.  But flow is initiated because there is lower pressure. A difference in stored energy. 

If you think there is no such thing as vacuum.  Remember we live in an atmosphere, and that is our point of reference.  If a tank has pressure and fails, it will spray out it contents or even explode.  A tank at vacuum fails, it will do the opposite of a pressurized tank.  It will draw in atmosphere or even implode.


So the Mythbusters filled a vented drum with a little bit of water. Heated the drum so it fills with steam. The drum is sealed air tight and removed from the source of heat. The steam cools.  The steam takes up roughly 1000 times more space than water. The cooling steam condenses, creating a vacuum in the drum. Once the pressure differential is great enough to overcome the strength of the steel drum, it implodes.

Think about that.  An open atmosphere caused the drum to implode.


I had a drum handy. Sat on it with my 200 plus pounds.  It held its integrity.  Maybe because the drum was air tight?  I removed the two inch bung plug.  Sat on top of the drum, and it held its integrity.  So I laid it on its side and sat on it, it held its integrity

I put the plug back in. Then shot some compressed air at it.  The sides, then the top.  The drum wobbled about a bit from time to time. But the drum held its integrity.  It was still in the same shape of a drum with no dents.
 
Now.  Think about that.  The drum was hit with compressed air, and the air flowed around it.  The compressed air never getting the advantage because it’s energy was equalized or consumed by the lower pressure of the atmosphere around the drum.

My weight didn’t harm or change the integrity of the drum.

But if a vacuum is drawn in the drum to cause a great enough differential pressure, the drum implodes.  And implodes in a fluid atmosphere with decreasing pressure with altitude.  The compressed air flowed around the drum without harm to the drum. 

How does the atmosphere gain the advantage to implode the drum.  To have the energy to do the work to move the walls of the steel drum inward?

I can take items of different densities and set them by each other.  A thing of lead and aluminum, and no work is done.  But use gunpowder to release energy to impart kinetic energy to a lead bullet, the moving bullet can do work on the aluminum block.

So what caused work to be done to move the walls of the steel drum.  Density in not a force. 

The atmosphere is fluid, and the flow of compressed air didn’t do work on the drum where the steel was failed.  The energy of the compressed air was “sunk” into the lower energy of the atmosphere.

How did the atmosphere have the energy to work on the drum to make it implode.

Well, there is pressure.  To have pressure, you have to expert a force to overcome the tendency of gas molecules to dissipate from each other to equalize with lower pressure.

Gravity exerts enough force to cause enough gas molecules to overcome their tendency to dissipate from each other to equalize to lower pressure to build pressure at sea level. Gravity causes individual molecules of N2, O2, CO2, and argon atoms to bunch up at sea level to create pressure. 

In the context of the implosion of the steel drum, gravity causes the air molecules to bunch up with enough force to cause a great enough pressure differential with enough energy to move the walls of the steel drum inward. 
« Last Edit: July 09, 2023, 12:32:56 PM by DataOverFlow2022 »

Re: Drum implosion vacuum pressure gravity work
« Reply #1 on: July 09, 2023, 01:48:19 PM »
With all due respect, what does this have to do with a round or flat Earth?

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JackBlack

  • 21969
Re: Drum implosion vacuum pressure gravity work
« Reply #2 on: July 09, 2023, 02:15:08 PM »
It is due to higher pressure.
Vacuum does not suck.

The "flow" is initiated due to the high pressure pushing, with the low pressure not being able to stop it.

I had a drum handy. Sat on it with my 200 plus pounds.
200 pounds is quite small.
Standard atmospheric pressure is roughly 101.3 kPa. That would be equivalent to roughly 10 337 kg for every m^2.
Your 200 pounds is pretty much nothing compared to that.

Try it with a coke can. I can easily crush that with my weight (once it is opened).

But if a vacuum is drawn in the drum to cause a great enough differential pressure, the drum implodes.
And it can also be done if you place the tank in a pressure chamber and increase the pressure.
Or if you just take it deep enough underwater.

How does the atmosphere gain the advantage to implode the drum.  To have the energy to do the work to move the walls of the steel drum inward?
The atmosphere always has that.
But if the atmosphere is also pushing from the inside out (or an equivalent or greater pressure is), then it wont be pushed in.

If you would like a simple example, consider a weight with 2 springs pushing hard against it; one on each side.
This holds it in place, but there is still a lot of energy stored in the springs.

If you remove one of the springs, the other will then accelerate the weight.
But it wasn't the absence of one of the springs causing it. It is the spring that is still there.

Re: Drum implosion vacuum pressure gravity work
« Reply #3 on: July 09, 2023, 04:56:57 PM »

Try it with a coke can. I can easily crush that with my weight (once it is opened).



If you are careful and ease you weight down, you can place your weight on the top of an empty coke can.  Then use a golf cub to dent the side, and it will collapse.  It’s been demonstrated a few times in 9/11 forums to show what happens if a column gets a structural flaw.

Then you can just stomp on the can to demonstrate the difference between static load and shock loading.