Stirlingengineforum.com

Induction heating is an interesting idea.

Flame on a metal tube also just allows a lot of heat to go around.

Does induction heating heat glass at all? I assume not, but it would heat a metal tube right?

How does induction heating work anyway? What would be the current needed to heat a little steel wool regenerator? What is an induction heating coil made of? Is this a potential DIY project? Like wrap a wire around the glass test tube and hook it to a flashlight battery? Like making an electromagnet? I assume it's not quite that simple, but I really have no idea. I really like the concept though.

An internet search turns up next to nothing that would suggest it's ever been tried, or even thought of before. Genius idea!

Induction coil

https://youtu.be/nlZl8YcKnLY

I can't think why this would not work but serious overkill, on the otherhand does anyone know how the coils / heaters in "Vapes" work, a friend of mine used to build them and I think he referred to them as induction coils. Unfortunately my friend is now a vaping statistic.

Toodlepip

Brian

If the link does not work google "12v induction heater" works on 5 to 12 volts and costs 5US dollars. Dont know how long a 9 volt battery would last.

https://www.aliexpress.com/item/4000277 ... hweb201603_

Toodlepip

Either of those draw way too much current.

I'm not sure if a tiny size induction coil for one of my engines exists, or could be constructed, but it doesn't look like a project I'll be embarking on any time soon.

Looks like I'll be trying the flameless lighter element to begin with.

It is interesting that the induction coil uses copper tubing. "Refrigeration tubing".

Refrigerators also have tiny capillary tubes:
Maybe could work for a tiny induction coil?

I don't know if I can help you much but I can share what I have learned over the years. As far as my engine design goes I did release the designs and they are still out there to be downloaded. The tube within a tube design actually has many purposes. Mainly creating a stack . The gap between the two tubes needs to be in a certain range for it to function. If the Gap is too small it creates too much restriction and if the Gap is too large there is too much turbulence. the goal is to keep all of the air molecules flowing nice and straight hence laminar flow. These engines are basically pulse engines where inertia is the main driving factor. I am nowhere near a scientist and do not claim to be. When you build these engines on a larger scale they are much easier to diagnose and improve just by measuring the RPM and most importantly just the feel of the performance. I'll give you an example. When the engine is cold and you crank it by hand it has a lot of compression but when it's up to operating temperature it's easily noticeable that when the piston is pushed inward and is actually compressing there is absolutely no resistance at all in fact it slightly gets pulled in . Not until the piston starts to decompress do you feel a large increase in pressure. You can easily push the piston in by hand and you think you should be feeling compression. Let me reword that. When the Piston is at the bottom of the compression stroke up until that point you feel no compression at all. The instant the Piston starts to move back towards the crankshaft you get a sudden Rush of pressure. It's like there is a low pressure zone created where the engine is being heated. When the Piston reaches its full stroke at the top closest to the flywheel the air is stretched like a rubber band and is briefly cooled. That's inertia . That rubber band effect is optimized by fine-tuning the gap between the two tubes.

Think of it as an alpha but removing one piston. You are now using laminar flow and momentum from the flywheel to displace the air to the hot side. Air molecules flowing in a nice straight line with no turbulence is key