Giovanni Campa (Energy)
Linear techniques can predict whether a given thermoacoustic system is stable or unstable. Since with a sufficiently large impulse, a thermoacoustic system can reach self-sustained oscillations even when it is linearly stable, a nonlinear analysis is required for predicting the self-sustained oscillations. The acoustic network code, called LOTAN, has been used in order to obtain the bifurcation diagrams for a simple Rijke tube. Several test cases from the literature have been analysed and very good results have been obtained, showing that it is easy to map the bifurcation diagrams as a function of the control parameters inside LOTAN. The shape of the bifurcation can be directly predicted from the flame model and from the transfer matrix.
