Stirling Engine design help

Hey,

I'm an electrical engineering student and I'm trying to design a solar dish which converts the heat from sunlight into electricity. I managed to make a small stirling engine with the results i got from google (The stirling engines made from coke cans). I was wondering how costly it would be to actually make or even buy a stirling engine of about 5 KW capacity.
Please reply if you have any experience with working with stirling engines.

Thank you,
Vidarth
 

mgb_phys

Science Advisor
Homework Helper
7,660
11
Last edited:
1,545
6
Making the Stirling engine is easy. Its making one thats efficient which is tough. In order to get even reasonable efficiency a thermal recuperator is required. The more efficient and less complicated designs use two pistons with a the recuperator in between them.

http://blog.steamshift.com/wp-content/uploads/moved/stirling_engine.gif [Broken]

Making something like this for 5kW would be a bit challenging but certainly doable if you got a mill on hand. If you don't have access to a machine shop, I would look at stirling engine electrical generators used in boats as a starting point.
 
Last edited by a moderator:
Making the Stirling engine is easy. Its making one thats efficient which is tough. In order to get even reasonable efficiency a thermal recuperator is required. The more efficient and less complicated designs use two pistons with a the recuperator in between them.

http://blog.steamshift.com/wp-content/uploads/moved/stirling_engine.gif [Broken]

Making something like this for 5kW would be a bit challenging but certainly doable if you got a mill on hand. If you don't have access to a machine shop, I would look at stirling engine electrical generators used in boats as a starting point.
Hey thanks a lot. Can you post some links about plans for a 5 kw stirling engine as i have access to a machine shop at university. Also do you know if any companies sell these commercially?
 
Last edited by a moderator:
Check out a group on Yahoo called SESUSA. Somebody there could help you out. I don't think you'll have much luck getting one to run off of solar power. People have spent millions trying to do it right and they could never make it affordable, despite decent results from the engine. Most the engines made at home aren't very efficient so starting with a low temp source like solar will probably doom you.
 
I have been "collecting" various yard related engines for this kind of purpose. you can decrease your cost of manufacture significantly with pistons, cylinders, and crank assy's "off the shelf. I am still looking for some "scroungable" engine with 90 degree cyl spacing, but the closest so far is an "old Mopar" air conditioning compressor. search google books for hot air engines and you should yield up some added info in a historical sense, but it still helps.

dr
 

RonL

Gold Member
1,066
211
Making the Stirling engine is easy. Its making one thats efficient which is tough. In order to get even reasonable efficiency a thermal recuperator is required. The more efficient and less complicated designs use two pistons with a the recuperator in between them.

http://blog.steamshift.com/wp-content/uploads/moved/stirling_engine.gif [Broken]

Making something like this for 5kW would be a bit challenging but certainly doable if you got a mill on hand. If you don't have access to a machine shop, I would look at stirling engine electrical generators used in boats as a starting point.
When I look at that picture the first thought is a model airplane engine, the second thought is a TEE pipe fitting, two opposed pistons in regular pipe sleeves, and a special machined aluminum or copper top sleeve. Charge it with propane and it should be a very cheap way to build. (use X or XX pipe fittings).

Bore the TEE through the center and weld a short nipple on each side to hold crankshaft bearings, then a pipe cap on each side will make a leak proof design.

To take power off don't forget about magnetic couplers, there are units that transfer a lot of power.

Ron

P.S. I have no idea what power, but 4" might get close?
 
Last edited by a moderator:

The Physics Forums Way

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving
Top