Generation of subharmonics and harmonics in the incompressible flows

Abstract

Based on the analyzing of the incompressible Navier-Stokes equations, the first part of this paper describes a mechanism about the generation of subharmonic. The results show that the large periodic pressure fluctuation can generate subharmonics. A hypothesis called less energy law is presented in the first part of this paper for the analysis of the reason why half subharmonic appears early than other subharmonics. The second part of this paper explains the phenomenon of the generation of harmonics, and proves that the non-linear interaction of fundament eigenmodes can excite infinite many harmonics. © 2001 The American Institute of Aeronautics and Astronautics Inc. All rights reserved.