How can I calculate engine dimentions for example, cylinder volume, diameter and the overall size of the engine>

Discussion on Stirling or "hot air" engines (all types)
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hond02pvu
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Joined: Wed Feb 27, 2019 8:26 pm

How can I calculate engine dimentions for example, cylinder volume, diameter and the overall size of the engine>

Post by hond02pvu » Sun Mar 03, 2019 2:07 am

How can I roughly calculate engine dimensions, for example, cylinder volume, diameter and the overall size of the engine? Based on differential temperature is 500oC, heat source is 500 kWt.

Thank you!

Bumpkin
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Joined: Fri Mar 02, 2012 1:42 pm

Re: How can I calculate engine dimentions for example, cylinder volume, diameter and the overall size of the engine>

Post by Bumpkin » Sat Mar 09, 2019 1:27 pm

I could have dropped a few zeros, but just for kicks I put a pencil to it. A VERY efficient Stirling could at max get 200 kw power from a 500 kw source. For a starting point, and only as an example; assuming a very efficient engine, with a hot end at 600 C and a cool end at 100 C - running 1000 rpm with atmospheric pressure, a 400 hp engine would need at least 20,000 cid power stroke total and around 40,000 cid total displacer swept volume. That's assuming nearly complete thermal cycling of the working gas. (which is very improbable) Extrapolate a higher displacement for a lower working gas exchange, and a lower displacement for moving more air/working gas with higher speed or pressure. Some math is down the page here: http://spragueriver.com/index.php/bumpkin-tech

Bumpkin

hond02pvu
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Joined: Wed Feb 27, 2019 8:26 pm

Re: How can I calculate engine dimentions for example, cylinder volume, diameter and the overall size of the engine>

Post by hond02pvu » Tue Mar 12, 2019 11:04 pm

It seems to be very useful. Thank you so much! Do you know what is the biggest Stirling engine been ever made? When I design the engine, I am confused about the speed. How can we determine the maximum speed of the engine?

Ian S C
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Location: New Zealand

Re: How can I calculate engine dimentions for example, cylinder volume, diameter and the overall size of the engine>

Post by Ian S C » Wed Mar 13, 2019 3:30 am

There have been Stirling engines use for car engines ranging from 100 hp to 175 hp, there are Stirling engines used in Swedish submarines of abut 100 hp. I can't find the reference point for it, but there are stationary power supplies built in shipping containers in Europe somewhere, advantage, silence.
Ian S C

hond02pvu
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Joined: Wed Feb 27, 2019 8:26 pm

Re: How can I calculate engine dimentions for example, cylinder volume, diameter and the overall size of the engine>

Post by hond02pvu » Wed Mar 13, 2019 9:58 am

It is very helpful for me. Thank you a lot. Do you know a reference paper mentioning 100-175 hp engine?

Ian S C
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Joined: Thu Dec 02, 2010 5:15 am
Location: New Zealand

Re: How can I calculate engine dimentions for example, cylinder volume, diameter and the overall size of the engine>

Post by Ian S C » Thu Mar 14, 2019 12:53 am

go to the top of the index page and you'll find Web links and magazine articles, and work your way through that, there are probably more on Google.
Ian S C

Johnwick88
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Joined: Wed Mar 20, 2019 8:01 pm

Re: How can I calculate engine dimentions for example, cylinder volume, diameter and the overall size of the engine>

Post by Johnwick88 » Wed Mar 20, 2019 9:34 pm

Check your machine specification or measure by adding engine oil and expecting the cylinder volume.

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