Geomorphs: Cochlea

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Definition of surface, in parametric equations:

x(u,v) = v cos(u)
y(u,v) = v sin(u)
z(u,v) = a u


  • u ranges from 0 to 6, scanning three full circles on the XY-plane (this produces three turns on the cochlear surface).
  • v ranges from 0 to 2, scanning the cochlea's surface from its vertical axis at the origin to its rim.
  • a is a constant having the value -0.42 in this plot; higher values of a make the cochlear "wave length" longer.

Note: The cochlea (in Greek: "kokhlias") is one of the devices attributed to the mathematician Archimedes, used in ancient times (some say even today, in certain places) for pumping up water from wells, when fitted in a tube.

Ancestor: Disc.

Descendants: Broken Accordeon.

Note: If you do not see Greek characters on this page, it is probably because the font you are currently using with your browser does not include the Greek code-page. In this page, character is pi.

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