autogyro wrote:flynfrog wrote:autogyro wrote:The problem of unburnt fuel and chemicals in the exhaust of the rotary, is because rotary engines are set to run rich for seal cooling/wear reasons. In a long narrow combustion chamber, the result is inevitably more unburnt fuel, even with the very best type of injection and ignition.
It is easy to burn all the fuel at high temperature in a two stroke using forms of stratified charge injection and even plasma ignition coupled to good port valve design and materials, I agree.
However it is still a two stroke cycle that is forced to use low compression and an exhaust / inlet overlap that will always result in a dirty induction charge.
I once built a Rover V8 outboard, with the engine stood on it's nose, with load bearings and oil system mods, driving an outboard leg. Turbocharged for 600bhp it was only a little heavier than the Mercury used on the OZ inshore cat that it was designed for.
I put buoyancy chambers under it to help when stationary and designed a ball mounted transom bracket for it that tilted the engine into the turn and the prop thrust line out but with the correct geometry to keep the tilt the same.
Turned much better than a conventional mount with far more power.
Work it out? We could make a fortune.
If the guy who ran the boat had not got back his Mercury sponsorship, it would have beaten Mercury into a cocked hat. two strokes pahhh
Please explain how you would use 'just a turbine'.
This has been tried on countless occasions and has always been wasteful on fuel and hopeless on tractability.
Just a turbine like almost every commercial jet liner uses for power. Or any commercial power plant.
I guess you are right 5 times the moving parts two forms of power transmission sound much simpler and likely to work that’s why people are doing this every where.
Maybe your poor sap driving your boat was worried that your one off engine might blow and he would be without an engine for the rest of the season.
not sure where you are getting two strokes are low compression. I am running very high compression in mine the alky motors are much higher. Not to mention the revs you can do when you dont have to worry about the piston hitting the valve train.
Compression ratio may be high in your two stroke and even higher in the alky one. The actual combustion chamber pressure will however, always be lower than a four stroke because induction air has to be used to scavenge exhaust gas from the cylinder. We do have an Italian two stroke four cylinder radial in a prototype aircraft however, that has a built in crankcase supercharger. This does produce high power figures by overcoming this failing to a large extent. Reliability then falls radically though.
Turbines are just about usable for racing cars that do not have to go round corners, or things like Abrahams Tanks that use complete oil fields for re fueling.
Of course we do not all live in American cloud cuckoo land.
Oh and it was not my boat and the V8 outboard and mount was and is very successful.
The guy in question died in a boat racing accident using a Mercury engine.
You are wrong on the chamber pressure its no different than a 4 stroke with a high overlap cam. It explains why I have to use 110 octane lead fuels. Its also why the AMA outlawed leaded fuels so they could keep the 3 year old two stroke bikes from beating honda newest 4 stroke time bomb
yes you can super charge 2 strokes GMC had the super charged and turboed 2 stroke semi engines. These engines were pretty reliable in there day less moving parts ect. than there 4 stroke counter parts not to mentions twice as many power cycles per rev.
Maybe you missed the part where the Abrams has 1500 hp and a bazillion ftlbs of torque so it might take a little more fuel than a prius. And who said you need on that big with electic coupling you could down size your turbine quite a bit and make up the rest with a battery reserve. You could then run the turbine at max load and peak effectiveness.
You are also wrong on the corner part. The Granitlli(sp?) turbines should have won Indy I believe it broke the rear end with only a few laps to go with a multiple lap lead.
We all know that in boats engines are often the cause of fatalities. Your success must have been great since you are cranking out boat engines left and right unlike mercury.
