熱音響現象の温度傾斜部のモデル化に関する研究

抄録

When there is a temperature gradient in a uniform pipe, self-excited acoustic vibrations occur at the resonant frequency of the pipe. In the previous research on the Rijke tube by Kamei et al., self-excited oscillation was generated by positive feedback of the particle velocity with a phase delay in front of the piston to the piston velocity. This study considers a model in which a one-dimensional acoustic tube with rigid walls on both ends is installed horizontally and a part of the area has a head purchase. A block diagram with positive feedback of the piston speed was considered, and a simulation was performed using the transfer matrix method. Also, it was confirmed from the change in the peak shape of the transfer function in the simulation that the self-excited oscillation occurred. In addition, we created an experimental device and compared it with the simulation. Finally, the damping ratio was obtained from the transfer function of the speaker and the evaluation point obtained in the experiment, and the characteristics of the temperature gradient of the heat source were obtained as the experimental coefficient.