Lighweight opposite 2-stroke engines

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WonderousMountain

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Apr 10, 2010
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2,184
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Clatsop, Or
A first order is once per revolution,
A second is twice per revolution, a
Third is three, a fourth is four. Often,
A single lancaster shaft is only able
to balance one order. Instead of mass
swinging around, it is now doing
jumping jacks, not too much gained.
 

jbiplane

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Jan 29, 2014
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289
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Krasnoyarsk, Russia
Francesco Testa from Italy, helped me with the 3d CFD of silencers-resonators for boxers.
With correct sizing, compact silencers invented by me produce same power as best linear.
Blue shows 2 individual silencers. Green and purple compact. Green has already been tested locally and in Holland. Most likely, they will work good for inline. Will check.
Сравнение классика сим спираль.jpg

The second picture shows the mass flow rate of exhaust gases per second at 9,500 rpm 118cc cylinder vs angle crankshaft rotation.Mass flow eng.jpg
 

Urquiola

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Aug 23, 2013
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Madrid, Spain
I insist in my opinion, and have no interests in this, besides I love Wankel Rotary Engines: 2-Strokes are not reliable enough for manned aircraft. About 2-Stroke design and tuning, there were some british books, you could probaly look for it at old book sites, as Abebooks, eBay, Bergoglio libri d'epoca,...
'Controlling two-stroke engine emissions', Automotive Engineering International, 2000-02-01 (a SAE Magazine) Blessings +
 
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mm4440

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Jan 14, 2012
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LA area, CA
Most ultralights and self launching sailplanes are 2 stroke powered and are normally manned. They as a class are less reliable than four strokes but they are adequate and affordable in those applications as they crash slow when the engine fails.
 

Urquiola

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Aug 23, 2013
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Madrid, Spain
Most ultralights and self launching sailplanes are 2 stroke powered and are normally manned. They as a class are less reliable than four strokes but they are adequate and affordable in those applications as they crash slow when the engine fails.
I'd say 'ultralights were 2-Stroke powered', self launching sailplanes are a different class, some takeoff just by sliding down on a slope, without any power help, the type of ultralight able to fly on two-stroke power can be considered inherently dangerous, from design, it are flyable only in days of 'Sun and flies', they could even be unable to carry a safety parachute.
Thanks. Blessings +
 
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mm4440

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Jan 14, 2012
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LA area, CA
Hi, a glider doing what is called a roll-off launch is still a glider. A self launcher is by definition, powered; 2 or four stroke, turbojet or electric have flown. Early rocket power experiments where done with gliders culminating in the Me 163, and the X 15 and Space Shuttle. Two strokes are going the way of steam engines as the future is electric.
 

dino

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Sep 18, 2007
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florida
Rotax 505 as used in the DG400 self launch motor glider ,which first flew in the early 1980’s has a spiral resonator
 
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