Patent ID: 6935098

Claim:
A turbomachine nozzle comprising: a substantially cylindrical inner barrel extending along a longitudinal axis of said nozzle; a centerbody disposed concentrically inside said inner barrel and extending beyond a free end of said inner barrel in the form of a substantially conical portion so as to define between said inner barrel and said centerbody a first annular channel for receiving a primary flow having a cross-section that is substantially constant around the entire circumference of said nozzle; and an outer barrel concentrically surrounding said inner barrel so as to define a second annular channel for a secondary flow; said free end of the inner barrel presenting a surface having a first series of undulations regularly distributed around said longitudinal axis of the nozzle, said first series of undulations being formed by negative undulations which extend radially inwards relative to said inner barrel, alternating with positive undulations which extend radially outwards relative to said inner barrel; wherein said centerbody presents a second series of undulations at least in a portion facing said undulating surface at the free end of the inner barrel, said second series of undulations being regularly distributed around said longitudinal axis of the nozzle, said second series of undulations being made up of negative undulations extending radially inwards relative to said centerbody, alternating with positive undulations extending radially outwards relative to said centerbody, said negative and positive undulations of said first and second series of undulations being of radial height that varies angularly and being disposed in such a manner that the negative undulations of said first series of undulations are disposed facing negative undulations of said second series of undulations, and vice versa, so as to generate turbulence and radial shear between said primary and secondary flows downstream from said first and second series of undulations, while conserving a constant flow section around the entire circumference of said nozzle.