INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Jobs

Stirling Engine Blowby?

Stirling Engine Blowby?

(OP)
Hello all! I have been trying to do some research on this subject but cannot seem to find much. I understand there is some blowby in a gasoline or diesel engine, but what about a Stirling Engine? Since it is an enclosed system of gas, how is that handled? Is the force too low for there to be a blowby effect because of the gases traveling between pistons so the force is dissipated before it can blowby?

RE: Stirling Engine Blowby?

They've never achieved commercial success, hence the lack of much information.

The ones that I've read about are completely hermetically sealed including the crankcase (if there is one) or integral alternator/generator (if there is one). Any leakage past pistons gets contained in the crankcase and the pressure and contents of the crankcase is the average of the engine's operating pressure, so leakage will be in both directions and average out to zero. The BMEP of a Stirling engine is pretty lousy and the difference between peak cylinder pressure and minimum cylinder pressure isn't much, so sealing of piston rings (given that the crankcase has the same gases in it) might not be so critical.

No one has put one in the hands of the average consumer and put 200,000 miles on one.

RE: Stirling Engine Blowby?

No, but they have put them in space and let them run continuously for years.
The delta P is so low that leakage is nearly nonexistent.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: Stirling Engine Blowby?

Small test ones have, they have never been the primary power on a project.
There are ones here on earth that have been run for years in testing also.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: Stirling Engine Blowby?

Stirling Biopower in Ann Arbor, Michigan have been making Stirling engines in low volume for years.
They were called STM when I visited them about 20 years ago, and had several units running durability at the time.
I think they sell the complete generator sets to landfills and livestock farms etc.
This patent may be helpful: https://www.google.com/?tbm=pts#tbm=pts&q=US+8...;*

PJGD

RE: Stirling Engine Blowby?

Model Stirling engines with low pressures use bellows instead of pistons and rings. Not sure how scaleable that is.

je suis charlie

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close