The article presents the results from experimental and numerical investigations of the parameters characterizing large-scale vortex structures formed in the models of various burners with flow swirling. The experiments included flow visualization and velocity field measurements carried out using a modern contact-less diagnostic system constructed on the basis of a laser Doppler anemometer. In addition, the frequency responses of unsteady vortex flow modes were investigated using dedicated acoustic sensors. The distribution of static pressure induced by an unsteady vortex was obtained using the phase averaging method. Along with experiments, the swirl flow parameters were calculated using an analytic theory and the Star CCM+ commercial software package. The adequacy of the mathematical modeling results was checked by comparing them with the physical experiment data.