熱音響現象の自励機構のモデル化に関する研究

抄録

Thermoacoustic self-excited vibration is a phenomenon in which the air in a tube becomes unstable by a temperature gradient and begins to vibrate at the resonance frequency and grows to a certain steady amplitude. Regarding the mechanism of thermoacoustic phenomenon, there is no literature that clearly describes the cause of self-excited. In this study, we created the simulation model using cellular automaton method for the thermoacoustic device using the loop-type acoustic tube. We also modeled the heat source with a temperature gradient. At that time, the fact that the excitation amount has a phase lag with respect to the particle velocity at the vibration point is derived from the one-dimensional heat conduction in the cross-sectional direction of the air vibrating in the pipe having a temperature gradient in the flow path direction, and the vibration amount is derived. We were able to reproduce the phenomenon in which the sound waves in the tube grow in a self-excited by expressing using the past particle velocities.