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Stirling Run on Electricity

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Matthew Monti

Student
Oct 23, 2023
26
I guess this runs on 120 rpm would a 24v 120 rpm dc motor do to power charging a phone or other portable devices?
 
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This is working concept of Stirling (handmade NOT mine) that does do the required RPM.

You need to review your Physics 101. RPM says nothing about power output; have you bothered to calculate the amount of power generated by burning wood? Is that not substantially different than that of a cup of coffee?


btw, the guy is getting 15 MW*s/kg of wood, i.e., he can provide 10W for 1.5 million seconds from 1 kg of wood, so about 17 days, instead of 8 seconds.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
What happened to all the critical thinking that exposure to the internet was supposed to bring about ?

Its the same with all these room a/c "engines" that run on a sparrow's fart of electricity.

There's so much quackery out there ... maybe there always was, just I didn't have to see so much of it.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.
 
I was looking at wind farms. I learned about how they convert lower RPM rotation of large blades and "convert" the lower rpm to the "higher" rpm for electricity. For this engine I am creating I like to learn more about this engine works and any resources will be appreciated. After all am very skeptical that I am wrong on that fact as it would be hard to find winds that meet over 1800 rpm ?! Maybe a tornado or hurricane but not wind you see daily. Perhaps this can be reimagined into stirling. Of course this would be expensive and have to be machined (no amazon or ebay parts). I don't know if this can be applied to stirling engine as even the modern marvels engine video showed use of steam turbines and NOT piston engines with high rpm for power generation. (Larger Power Engine idea - in progress)

Second idea steam powered portable device to use for power generation phones in case of emergency from a tea kettle. This would NOT be stirling powered.A device like this would be used in emergies or when camping where you don't have access to electricity. A device would be nice for long term emergies where access to daily good hard. Same reason you still see kerosine lamps sold despite better technology (more light and hrs ). Looking at small steam turbine engine. Think about it long term usage (batteries age and break bad emergencies). Solar powered phone charge up only work when weather pending (bad for emergencies).
 
Forget the stirling engine you demonstrated via enough post not enough RPM.
Let me reframe the question.
How do you get a wind powered generator from LOW RPM CONVERTED to HIGH RPM?
If

This is my question.
We established the lower power output of Stirling in past posts.

I am NOT engineer am some trying a concept as a hobby.
 
Wind turbine blade speed is typically 10-15 rpm. This is because the centrifugal forces (among others) acting on the blade limit the speed at which the materials will remain structurally intact. That kind of rpm doesn't sound like much, does it? Remember that the blades describe a diameter of nearly 100 m - which means the outermost tip is moving at roughly 375 km/h.

The generator inside the nacelle (that little "house" on top of the pole) has to be physically small - but also be able to output the required power (kilowatt). Machine volume is directly related to the amount of torque - so a small volume with a lot of power requires a high speed. The actual "design speed" of the generator is a function of the local power grid - North America uses 60 Hz, so truly synchronous speeds are going to be (120 * 60 / poles). That means a North American wind turbine will have the generator shaft turning at something close to 900, 1200, or 1800 rpm (8 pole, 6 pole, or 4 pole) depending on design. So how do we get from the high-speed of the generator shaft to the low speed of the blade shaft?

The answer is mechanical advantage in the form of gearing. A wind tower has a HUGE gearbox located just inside the "nose" of the nacelle, close to the blades. The gearing is done in multiple steps because of the very high "final drive" ratio. What is the final drive ratio? It is the ratio of generator to blade speed - so perhaps 1200-to-10, which is the same as saying 120-to-1. For comparison purposes, a car with a high-torque gear train will have a final drive ratio of around 3 to 1.

Industrial processes work the other way: the "driver" is the high speed motor, powering a low-speed process (such as the machines used to roll metal). The same gearing approach works for them too - the gearbox does not care which direction the mechanical advantage is used.


Converting energy to motion for more than half a century
 
Gr8blu (Electrical)

Thank you for clarifying issues I am self reading about self engineering books and would update not posts to this forum.
 
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