'Shock diamonds' (also known as 'Mach diamonds' or 'Mach disks') are a formation of
shock waves in the
exhaust plume of an aerospace propulsion system, such as a supersonic
jet engine,
rocket,
ramjet, or
scramjet. It is formed when the supersonic exhaust from a
nozzle is slightly over or under-expanded, meaning that the pressure of the gases exiting the nozzle is different from the ambient pressure. A complex flow field results as the shock wave is reflected at the free jet boundary, and the visible diamond-shaped pattern that gives the shock diamond its name is formed.
External links
★ http://www.aerospaceweb.org/question/propulsion/q0224.shtml
★ http://science.nasa.gov/headlines/y2007/04may_methaneblast.htm?list208336 Shock diamonds forming in NASA's methane engine
See also
★
Shock wave