캔-환형 연소기의 방위 방향 자발 불안정성

Abstract

Driving mechanisms of self-excited azimuthal instabilities of can-annular lean-premixed combustors were experimentally investigated in combination with 3D FEM-based eigenvalue analysis and acoustic wave decomposition method. We show that the fluctuation energy required to excite a standing azimuthal mode in annular cross-talk section is supplied locally in individual combustors by meeting the Rayleigh criterion, while the behavior in four combustor sections is dictated by degenerate longitudinal-mode at the same frequency.