PERTURBATION-METHODS FOR BIFURCATION-ANALYSIS FROM MULTIPLE NONRESONANT COMPLEX EIGENVALUES

It is shown that the logical bases of the static perturbation method, which is currently used in static bifurcation analysis, can also be ap plied to dynamic bifurcations. A two-time version of the Lindstedt-Poi ncare Method and the Multiple Scale Method are employed to analyze a b ifurcation problem of codimension two. It is found that the Multiple S cale Method furnishes, in a straightforward way, amplitude modulation equations equal to normal form equations available in literature. With a remarkable computational improvement, the description of the centra l manifold is avoided. The Lindstedt-Poincare Method can also be emplo yed if only steady-state solutions have to be determined. An applicati on is illustrated for a mechanical system subjected to aerodynamic exc itation.