High Level Noise-Induced Bypass Transition in Compressible Plane Poiseuille Flow

Abstract

A numerical experiment is conducted to study the bypass transition of compressible plane Poiseuille flow. The space and time development of the disturbances into streaks is captured by employing a spatial DNS, which although requires more computational resources than the temporal one, allows having a full picture of the process. The generation and algebraic growth of the streaks, which are lifted away from the walls and oscillate in the spanwise direction, characterize the transition. The numerical results give some answers related to the transition of compressible plane channel flows, initiated by large amplitude random disturbances, and point to the universality of the breakdown mechanism in wall bounded flows (incompressible and subsonic) and to the important role of the near-wall streaks.