JDM tuner
April 1st, 2006, 06:33 PM
ok we all hear about rotary engines here and there from rx7's and other mazda's and cars .... but seems that there aren't many people who are interested in exploring how those engines works and who invented & inspired this Magic ....:tudevil:
Felix Wankel received his first patent for a rotary piston engine in 1929, five years after he first hatched the idea and 27 years after his birth in Lahr, Germany.Over the next decade and a half and during WW2, Wankel was involved in the development of a rotary disc type valve for use in aircraft and torpedo engines, thereby shelving the rotary engine project, and he held jobs at BMW, DVL, Daimler-Benz, Lilienthal and Junker Aircraft. Because of his military involvement, following the invasion of Germany in 1945 he was imprisoned until 1946, and his workshops and research were destroyed by French troops, further delaying his rotary research until 1951, when the German company NSU became interested in the project.
Um...ok, so how's it all work? Well, see here, it's like this dude: The heart of a rotary engine is the rotor, which is a trochoid (roughly triangular) shaped component whose convex faces each act as pistons. There are usually a pair of them per engine, 180 degrees out of phase and slightly offset from the centre of rotation. Each rotor is housed in a rotor housing (!), which are epitrochoid (roughly oval) shaped and the two rotor housings, one for each rotor, are joined at the hip and capped on the ends by the side housings, thereby creating nice, cosy homes for the rotors. Running straight through the middle of this mess is the eccentric (or output) shaft, which has two smooth round lobes called journals mounted eccentrically, which mate with the bearings of their respective rotors. These lobes act somewhat like crankshafts in a piston engine, since any force that the rotor applies to the lobes creates torque in the shaft, causing it to spin. Attached to each end side housing is a stationary gear that is...em, stationary. Their outward pointing teeth mesh with inward pointing ones of the rotor gear, for the rotor contains both a smooth bearing and an internal gear, and keep everything in sync.
The rotor moves inside its housing in a really weird kaleidoscope kind of way. Its motion is the combination of the rotation about the shaft journal and the orbit of the eccentrically situated journal. These motions, synchronised, create the desired planetary motion, which also happens to look very pretty. In this way, the rotor's vertices always maintain contact and a seal with the rotor housing, thereby creating three gas chambers inside the housing, one for each rotor face.
In its rotation, a chamber starts out really small and expands, as it passes over the intake port and takes in a big gulp of the air/fuel mixture. As the chamber subsequently gets cut down to size, the mixture is compressed and ignited by the spark plugs near top dead centre, where the chamber has reached its smallest capacity. The combustion pushes the rotor, and therefore the journal and eccentric shaft through the power stroke, before the gasses are released as the chamber passes over the exhaust port, before restarting its cycle.
Well, that's all nice and good, and if you understood all that mumbo jumbo you're probably ahead of the game already, but what's the point? Well, see here yo, it's like this: First of all, a rotary engine is about 3 times lighter and more compact than a reciprocating engine (that's the kind you find in your Explorer, which goes up and down not round and round), utilising about 48% fewer parts and containing all of 3 moving components (compare that to 40 in a conventional engine)! By doing away with the reciprocating motion of a reciprocating engine, a rotary unit is also much smoother and can spin much faster, however the lack of torque at low speeds partially offsets this advantage by leading to greater fuel consumption. Wankel's long and narrow combustion chamber has a high surface to volume ratio, which makes it less thermodynamically efficient, but the cooler combustion leads to fewer nitrogen oxides emissions.
i hope someone appreciate all this .... I just wanted to teach the ignorants how we do ...:king:
Felix Wankel jr.
Felix Wankel received his first patent for a rotary piston engine in 1929, five years after he first hatched the idea and 27 years after his birth in Lahr, Germany.Over the next decade and a half and during WW2, Wankel was involved in the development of a rotary disc type valve for use in aircraft and torpedo engines, thereby shelving the rotary engine project, and he held jobs at BMW, DVL, Daimler-Benz, Lilienthal and Junker Aircraft. Because of his military involvement, following the invasion of Germany in 1945 he was imprisoned until 1946, and his workshops and research were destroyed by French troops, further delaying his rotary research until 1951, when the German company NSU became interested in the project.
Um...ok, so how's it all work? Well, see here, it's like this dude: The heart of a rotary engine is the rotor, which is a trochoid (roughly triangular) shaped component whose convex faces each act as pistons. There are usually a pair of them per engine, 180 degrees out of phase and slightly offset from the centre of rotation. Each rotor is housed in a rotor housing (!), which are epitrochoid (roughly oval) shaped and the two rotor housings, one for each rotor, are joined at the hip and capped on the ends by the side housings, thereby creating nice, cosy homes for the rotors. Running straight through the middle of this mess is the eccentric (or output) shaft, which has two smooth round lobes called journals mounted eccentrically, which mate with the bearings of their respective rotors. These lobes act somewhat like crankshafts in a piston engine, since any force that the rotor applies to the lobes creates torque in the shaft, causing it to spin. Attached to each end side housing is a stationary gear that is...em, stationary. Their outward pointing teeth mesh with inward pointing ones of the rotor gear, for the rotor contains both a smooth bearing and an internal gear, and keep everything in sync.
The rotor moves inside its housing in a really weird kaleidoscope kind of way. Its motion is the combination of the rotation about the shaft journal and the orbit of the eccentrically situated journal. These motions, synchronised, create the desired planetary motion, which also happens to look very pretty. In this way, the rotor's vertices always maintain contact and a seal with the rotor housing, thereby creating three gas chambers inside the housing, one for each rotor face.
In its rotation, a chamber starts out really small and expands, as it passes over the intake port and takes in a big gulp of the air/fuel mixture. As the chamber subsequently gets cut down to size, the mixture is compressed and ignited by the spark plugs near top dead centre, where the chamber has reached its smallest capacity. The combustion pushes the rotor, and therefore the journal and eccentric shaft through the power stroke, before the gasses are released as the chamber passes over the exhaust port, before restarting its cycle.
Well, that's all nice and good, and if you understood all that mumbo jumbo you're probably ahead of the game already, but what's the point? Well, see here yo, it's like this: First of all, a rotary engine is about 3 times lighter and more compact than a reciprocating engine (that's the kind you find in your Explorer, which goes up and down not round and round), utilising about 48% fewer parts and containing all of 3 moving components (compare that to 40 in a conventional engine)! By doing away with the reciprocating motion of a reciprocating engine, a rotary unit is also much smoother and can spin much faster, however the lack of torque at low speeds partially offsets this advantage by leading to greater fuel consumption. Wankel's long and narrow combustion chamber has a high surface to volume ratio, which makes it less thermodynamically efficient, but the cooler combustion leads to fewer nitrogen oxides emissions.
i hope someone appreciate all this .... I just wanted to teach the ignorants how we do ...:king:
Felix Wankel jr.