Numerical Analysis on Heat-Induced Vibration of Air Column.

Phenomena such as singing flame or Rijke tube are heat-induced vibrations of air column in a tube, which are coupled with heated fluid motion.In this paper, computation of air column vibration with local heat input is carried out to the extent that amplitude of pressure variation is fully increased and amplitude growth rate is saturated.Computed amplitude growth rates are compared with those obtained by experiments for a vertical tube and computational validity is assessed.From the computational results, it appears that both the fluid behavior around the heater and the energy dissipated by viscosity influence the amplitude growth rate of pressure variation.The energy of driving or damping air column vibration is estimated and discussed for explaining the mechanism of air column excitation.