The lean premixed combustion allows for reducing the production of thermal NOx, therefore it is largely used in industrial combustion. Lean premixed combustors are, however, prone to combustion instabilities. An analytical model was developed by Buchner 14] in order to predict the stability limits of combustion systems. A significant input of this model is the damping ratio, which should be determined from experiment or numerical simulation. In the present work a numerical investigation of the pulsating, non-reacting flow in a model combustion chamber and a coupled system of burner plenum...