Search found 88 matches

by staska
Tue Apr 26, 2022 12:08 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Engine design sanity-check
Replies: 10
Views: 5127

Re: Engine design sanity-check

Hello. Will it be atmospheric or pressurised ? For 100 cc at 3-5 bar you would in 100-200 watts of power if you heater and cooler is right.
by staska
Sun Mar 13, 2022 2:57 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: My "Custom" Stirling Engine Workshop
Replies: 38
Views: 21890

Re: My "Custom" Stirling Engine Workshop

You need metal working lathes.. a lot of them. And a skill to use them :)
by staska
Sun Mar 06, 2022 1:52 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: aluminum piston and or cylinder
Replies: 9
Views: 10386

Re: aluminum piston and or cylinder

Technical capabilities - how big and good lathe do you have. Ie - i cant make good cast iron finishi, i have to give it for honing/polish. But alu is ok.

Cup seal or rings - cup seal is so much easier to make. But it is limited for 3-5 bar difference max. And wotks as one way valve too.
by staska
Sat Mar 05, 2022 1:30 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: aluminum piston and or cylinder
Replies: 9
Views: 10386

Re: aluminum piston and or cylinder

Ok. Which technical capabilities do you have ? I turn them from stock, or cut disc in washer form from thin sheet. https://www.google.com/url?q=https://core.ac.uk/download/pdf/35462647.pdf&sa=U&ved=2ahUKEwjs4vuUx672AhWWyosKHRtwAd0QFnoECAkQAg&usg=AOvVaw3PjWRGm_pF3GtG4BFvUh7f Page 124 will...
by staska
Wed Mar 02, 2022 11:37 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: aluminum piston and or cylinder
Replies: 9
Views: 10386

Re: aluminum piston and or cylinder

Hard anodized alumium and ptfe is on of the classic solution for stirling engines.
by staska
Wed Feb 23, 2022 11:18 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: High temperature displacer
Replies: 191
Views: 80912

Re: High temperature displacer

Just do it in metal. Like from old candy box. Or just two pieces of 0.1mm ss foil with rolled sides and some tack welding.
by staska
Tue Feb 22, 2022 12:25 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: SWEPT VOLUME - SIZE OF AN ENGINE
Replies: 3
Views: 2936

Re: SWEPT VOLUME - SIZE OF AN ENGINE

Its all depends on configuration. 90 degree alpha with equal bore and stroke per cylinder swept volume is equal to 1.41 x single cylinder swept volume. For beta/gamma - equal to power cylinder. But phase angle is not equal to fisplacer and power piston angle differencies. Add different swept volumes...
by staska
Mon Feb 14, 2022 1:49 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: AlphaGamma
Replies: 18
Views: 7927

Re: AlphaGamma

by staska
Tue Jan 18, 2022 9:57 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Alpha Configuration Advice
Replies: 3
Views: 6142

Re: Alpha Configuration Advice

I think that "maritime" is another name for an engine with a cross-head mechanism in place of trunk piston. https://en.wikipedia.org/wiki/Crosshead Which is plus and minus for stirling engine. Where all goes to small details. And you could fold you mechanism, and have a cross-head in the b...
by staska
Tue Jan 11, 2022 9:53 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Large piston rings/sealing
Replies: 14
Views: 3199

Re: Large piston rings/sealing

Unfortunately I have an NDA for some of the 'novel' design aspects of our engine so I cant share all of the necessary info. Thank you for pointing me towards some useful engines and data though. Its impressive to see the amount of work shared on this forum. Contribute yourself too on it. But was th...
by staska
Tue Jan 11, 2022 7:31 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Large piston rings/sealing
Replies: 14
Views: 3199

Re: Large piston rings/sealing

That's awesome, did you create this code? Is it available? I rewrite from old FORTRAN code found in some scholar papers. I can run numbers for you. I need following data : Compression space, expansion space + dead volume of each of them. On heater / cooler i need number of tubes / slots, length and...
by staska
Tue Jan 11, 2022 12:58 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Large piston rings/sealing
Replies: 14
Views: 3199

Re: Large piston rings/sealing

Sorry, I don't have the material data sheet for the rings. They are Carbon finber filled teflon from https://www.hitechseals.com/index.asp?lang= and yes, they are oring backed. The oring is Viton, bringing the max temp for the seals down to 200C. I do have all of the geometric data, I modeled the e...
by staska
Mon Jan 10, 2022 2:51 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Large piston rings/sealing
Replies: 14
Views: 3199

Re: Large piston rings/sealing

Could you share data of that graphite ptfe ? I think it is different than mine. So you have oring backed graphite ring ? Tolerance or no - but if you do not give it any pressure - friction will eat all of you power. Or most of it. Learned that hard way. And for that 1 kw you need about 3-4 liters of...