Author Topic: Model Engine running just off a naked flame  (Read 350 times)

Offline Jim Dobson

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Model Engine running just off a naked flame
« on: July 17, 2025, 07:31:45 PM »
This is a Model Engine running just off a naked flame, thought some might be interested in seeing it run.
They are most commonly called Flame Licker Engines or Flame Gulper Engines or Vacuum Engines.
Very interesting to muck around with and I've done a lot of modifications and work on this one -


Offline BillTodd

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Re: Model Engine running just off a naked flame
« Reply #1 on: July 18, 2025, 03:32:49 AM »
That runs really well  :bow:

They are fascinating engines. They actually work using a phase change between the fourth state of matter , called plasma,  and  a gas .

The flame (or at least the blue part) is so hot the molecules are ripped apart in to charged ions in a very low density plasma. When they cool , they rapidly condense into a hot gas that is relatively much denser causing a partial vacuum. 

The plasma cools entirely through radiation, so polishing the inside of the bore will make a few more photon to bounce back into the plasma and keep it hot . That'll allow a bit more of the good stuff into the cylinder before the valve closes. 

Also it's important that the hot gas can escape the cylinder as the piston comes up . The vavle should spring open to allow this.
Bill

Offline Jim Dobson

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Re: Model Engine running just off a naked flame
« Reply #2 on: Today at 12:06:48 AM »
That runs really well  :bow:

They are fascinating engines. They actually work using a phase change between the fourth state of matter , called plasma,  and  a gas .

The flame (or at least the blue part) is so hot the molecules are ripped apart in to charged ions in a very low density plasma. When they cool , they rapidly condense into a hot gas that is relatively much denser causing a partial vacuum. 

The plasma cools entirely through radiation, so polishing the inside of the bore will make a few more photon to bounce back into the plasma and keep it hot . That'll allow a bit more of the good stuff into the cylinder before the valve closes. 

Also it's important that the hot gas can escape the cylinder as the piston comes up . The vavle should spring open to allow this.

G'day Bill, thanks for the post I enjoyed reading that.
I have a fair to middling collection of these now and they never fail to amaze me how they work.
Hope you have a great weekend.
Cheers,
Jim