Oddball engines and prototypes

[tjbw]

http://www.pattakon.com/pattakonPatATeco.htm

Not the same at all.

Manolis has given a lot of thought to engine designs, and has many interesting projects at pattakon.

He could look at the drawing I posted, and within minutes offer a better solution, as could many others here.

[Hemi Makutu]

Not the same at all.

Manolis has given a lot of thought to engine designs, and has many interesting projects at pattakon.

He could look at the drawing I posted, and within minutes offer a better solution, as could many others here.

It was meant in jest, since the apparent simplicity of 2Ts does belie the exactitude of making them work well..

[Frits Overmars]

It was meant in jest...

I guess people still have to get used to the new, improved Hemi .
Keep up the good work mate.

[Hemi Makutu]

I guess people have still got to get used to the new, improved Hemi .
Keep up the good work mate.

Well rounded or what eh, chippie?

http://cdn.intechopen.com/pdfs-wm/43662.pdf

[tjbw]

Well rounded or what eh, chippie?

http://cdn.intechopen.com/pdfs-wm/43662.pdf

Yes, I think of you as hemispherical hemi makatu

Nice link, thanks.

[lohring]

Well it's the weekend, so some might like to contemplate this drawing.

To be fair the author commented on a revision to this shortly after it was posted, perhaps he should have corrected the drawing too.

If the designer expected to actually increase the power he would need to increase the exhaust back pressure along with the intake pressure. A turbocharger is a better (and widely proven) solution.

Lohring Miller

[tjbw]

If the designer expected to actually increase the power he would need to increase the exhaust back pressure along with the intake pressure. A turbocharger is a better (and widely proven) solution.

Lohring Miller

No lag with the supercharger. I'd love to see some of the proven solutions, including more photos and info on the engine in your post. I'm aware that some large two stroke marine engines use poppet exhaust valves with a turbocharger.

Retrofitting a 'charger to an existing 2 stroke engine can result in the additional mixture getting blown out the exhaust port, and would indeed require exhaust redesign to return the additional mixture to the cylinder.

Whilst I'm not convinced that the complication is worthwhile, I'd love to play with one of these:

[tjbw]

Recently we had a look at a Villiers V4 2 stroke which used a supercharger to send mixture to a shared crankcase.

Here's an old NEC V4 liquid cooled 2 stroke, it was built in 1910. It has a 3 chamber supercharger. Two of the chambers send air direct to the piston controlled transfer ports. The third chamber sends mixture to a cylindrical rotary valve, which then opens after the transfer port. The objective being to purge exhaust gas, from the cylinder, before mixture is transferred via the transfer ports.

Other features include, cast iron cylinders with integral head, cast iron deflector pistons, and copper water jackets.

This engine, which is on display at the Science Museum in London, is thought to be the first supercharged aero engine, and it is featured in Setright's book "Some Unusual Engines"

Some more photos and text here:
http://www.practicalmachinist.com/vb.../t-112596.html

[tjbw]

Well it's the weekend, so some might like to contemplate this drawing.

To be fair the author commented on a revision to this shortly after it was posted, perhaps he should have corrected the drawing too.

I guess the problem with the drawing I posted was due to the graphics being delegated to someone who didn't fully understand the request, which was to add a breather hole at the top of the transfer port. The hole was added, but the transfer was shaded (closed), so no mixture would ever reach the cylinder. It doesn't help either if the centrifugal supercharger is rotating in the wrong direction.

[tjbw]

Here's a 13 minute video, uploaded by VisioRacer on youtube, with "14 unconventional engines". Includes 2, 3, 4, 5 and six cylinder engines, and also a Rolls Royce turboshaft engine.

https://www.youtube.com/watch?v=iaCIidQ1Mjs

[lohring]

No lag with the supercharger. I'd love to see some of the proven solutions, including more photos and info on the engine in your post.

Snowmobiles have run turbochargers like the engine pictured for a long time. Some ran variable vane turbines to reduce lag. The engine pictured developed around 800 hp with nitrous injection. Below are some more pictures.

The most noted supercharged and/or turbocharged two strokes were the Napier Nomad and the Rolls Royce Crecy. Single cylinder test engines for the Crecy developed a BMEP of 321 psi with an intake pressure of 36 psi and an exhaust back pressure of 12 psi. Gas turbines were a better solution for aircraft.

Lohring Miller

[Hemi Makutu]

These may be of interest to some, the Sabre also being a powerful piston aero-engine, that did see service.

http://www.hawkertempest.se/index.ph...ergio-pasquale

[Hemi Makutu]

https://researchbank.rmit.edu.au/ese...1450/Jiang.pdf

[Hemi Makutu]

The 500cc H1 Kawasaki and the 750cc H2 were the ultimate in unmanageable street bikes, but they did thrill (and kill) us young "tossers" so that was the end of the British bikes.

I bought my 1st H1 as a ride to work commuter, partly because I didn't want wear out my sporty Triumph
doing such mundane miles, & partly because in those days it was too likely to be stolen, if left outside.

I got flak from my Brit-bike mates for going Nippon & 2T, but yet, they had to respect its capabilities..

H1 was not "unmanageable" - at 500cc it had enough low rpm torque to purr about on, even economically,
& with the powerful electronic ignition, not foul plugs either..

They didn't steer nicely like the Brit bikes of the day, for sure - despite Kawasaki changing the angles etc,on
every model change, but stay rubber side up & the ground clearance/roadholding was ok..

The H2 was even more docile, but as shown below, made a good production racer, even in Europe.

http://www.kawi2strokes.com/forum/vi...hp?f=22&t=1350

[Frits Overmars]

I stumbled upon this video: https://www.youtube.com/watch?v=SL1uwRtqPWE
Crank phase variaton on the fly - I love it.
I just hope Flettner doesn't see this; I'm afraid he wouldn't be able to resist...