Animated Engines

[aeronca65t]

This is not strictly "tools", but it's sort of related.

For those of you who are wondering how various engines work, this site has some great "moving GIF" schematics that illustrate things nicely (including the common 4-stoke engine):

https://www.keveney.com/Engines.html

 

[kennypinkerton]

I built a "visible 4 cylinder turbocharged engine" model when I was 11-12 years old... Really cool thing! I still have what's left of it around here somewhere. the cat knocked it off the entertainment center one night while I was sleeping.

 

[Deleted member 3577]

Notice anything odd about the points on the 4 cylinder?

 

[Ken G]

I don't think that would work very well with a conventional coil ignition, or only at very low revs! Fine with a capacitor discharge one though.

Ken G, 1925 Rover 16/50 with a high voltage magneto (San Francisco)

 

[kennypinkerton]

You mean the 4-stroke? Looks like open too long, and closed too breifly to me. /ubbthreads/images/graemlins/thumbsup.gif

 

[aeronca65t]

[ QUOTE ]
Notice anything odd about the points on the 4 cylinder?

[/ QUOTE ]

I'm sure you mean the 4-stroke.......but, no, I don't see anything odd.
The "dwell closed" time (points closed) looks about right to me for a one cylinder engine.

 

[lawguy]

[ QUOTE ]
Notice anything odd about the points on the 4 cylinder?

[/ QUOTE ]

Other than the fact that it appeared to fire when the points closed instead of open...nothing.

 

[Banjo]

hmmm, the sterling engine is intreguing. I would like to build one, or find one to experiment with

 

[GregW]

If I remember correctly, the sterling engines work, but they don’t have any oomph. I don’t think they are strong enough to run a fan in your living room.

 

[Nunyas]

they've made some advancements in that technology. I read an article a while back where they coupled a sterling engine with solar energy to generate power. It seemed the proof of concept engine was much more efficient at generating the "correct" power (Solar cells generate DC that needs to be converted to AC), and generated more of it. The only power development comparison I can recall was against solar cells.

I can't recall if they compared against wind or any of the other 'clean' sources, and if they did I don't know what metrics they used for the comparison.

 

[DrEntropy]

[ QUOTE ]
[ QUOTE ]
Notice anything odd about the points on the 4 cylinder?

[/ QUOTE ]

Other than the fact that it appeared to fire when the points closed instead of open...nothing.

[/ QUOTE ]

I perceive the "fire" to occur as the points (break) open... but I'm famous for poor timing /ubbthreads/images/graemlins/jester.gif

 

[Deleted member 3577]

[ QUOTE ]

Other than the fact that it appeared to fire when the points closed instead of open...nothing.

[/ QUOTE ]
Yep.....That's what got me.

 

[DrEntropy]

You guys on a dial-up connection? /ubbthreads/images/graemlins/devilgrin.gif

 

[70herald]

[ QUOTE ]
I don’t think they are strong enough to run a fan in your living room.

[/ QUOTE ]

Actually, in the pre-electric era, stirling engine fans were not uncommon. They mostly used small alcohol burners to power them. These fans are now quite valuable, and there are even reproductions being made. One of those toys I really would like to own, but don't risk actually buying since it might be the toy that angers the wife enough to put my Herald in real danger /ubbthreads/images/graemlins/mad.gif

The problem with using a stirling engine for a car, is not the lack of power output, rather that of controlling the engine. Power output on a stirling engine is determined by engine volume, and temperature difference between the hot and cold pistons. Obviously, the volume can be designed for any given application. However temperature difference is a real problem. There will inevitably be a delay between changes in power required, and the cylinder heating or cooling to match the power required. This problem can be "solved" by adding a throttle valve between the high and low temperature sides of the engine. In this case, the response can be virtually instant, however with a loss of efficiency. This is the approach that GM took with the stirling engines they built (but didn't sell) in the '60s. Given the design of modern hybrids, which basically use the electric motor to control the "throttle" and kick the gas engine in at its maximum efficiency, it should really be possible to use a stirling in a hybrid design quite effectively, and get really good gas mileage.
Yisrael

 

[GregW]

I agree, I’ve done a little reading over the last couple of days. Here is an interesting site devoted to Stirling engines. Including stirling powered submarines. https://www.stirlingengine.com

 

[Banjo]

Yea Seeing that GIF caused me to go on a multi hour tangent search on Sterling engines. I read about the use in cars (mainly that it was difficult because of the throttle response) and how they would work well in hybrids, and found the site that sells small engine kits for science classes, and a site that sells a fan that sits on top of a woodstove (good idea), and a site that had vintage engines for sale, and a team that is building an engine that is contained in a propane cylinder....
and how they were popular as agricultural engine in the 1800s.
I was also intregued to see the true setup for an atckinson cycle engine. Toyota uses a varation of that in the Prius, but it's very different than the original type

 

[kennypinkerton]

Best one (but almost the most useless one) I've seen... run's while sitting on top of a cup of hot coffee.

 

[Banjo]

The site with the science class engines sells that one coffee cup engine
It's not usless if it sparks the intrest of the right person. But yea, it don't really do nuttin.
I still want one.

 

[aeronca65t]

I have one of those coffee-cup engines on my desk at work...they really do work.
All my first semester kids build an oscillating steam engine.

Along with my steam site , Roy Rice's site is pretty good too:

https://www.geocities.com/~rrice2/

I looked at that moving GIF of the 4-stroke engine, stopping it at certain times......to me, it looks like the points are opening just as the spark occurs (which is correct).

 

[kennypinkerton]

I like that gearless engine... pretty neat stuff... And steam is king!