What is the technical name of the shape of the rotor in a rotary engine. I know its a stupid question, just wondering. Thanks

 

My first impulse was to go with triangle, but I know there is a much larger word that describes it much better.

 

The inside of the rotor housing is a peritrochoid shape, and the rotor is shaped to fit inside of it. I guess the rotor shape is best described as a Reuleaux triangle. Hopefully some of the advanced math folks on the forum can come up with a more accurate description.

 

Rotors are similar to, but not exactly, Reuleaux triangles. They are more flattened on the faces than a true Reuleaux triangle.

 

if you want to know about geometry then this is interesting reading.

http://www.personal.utulsa.edu/~kenn...n/chapter7.pdf

this paper gives some interesting insight into eccentricity ratio and some other cool things. evil aviator.. i believe that is an accurate description of the shape.

 

i don't know if this is very helpful, but you might want to see what organic chemists have to say about the shape of cyclopropane. i remember when i was taking orgo, the stress of the bond made it curve like a rotor. worth a shot, eh?

oh and monkhommey, thanks for that paper.

 

http://en.wikipedia.org/wiki/Reuleaux_triangle

http://en.wikipedia.org/wiki/Epitrochoid

 

The rotor shape is called a 3-flanked Hypotrochoid, which is the inner envelope of a 2-lobe Peritrochoid. This according to Rotary Engine by Kenichi Yamamoto.

 

Blake wins.

 

trochoid rotors spinning in an epitrochoid curve.

 

Big.....Words...... Hurting...... Brain.........

Why not just call it an inflated triangle.

Edit: better yet, a triangle.... WITH BOOST!

 

i would say the description most likely to be understood by your friends is: "its like one of thsoe 3d doritos"