Jet resonance in truncated ideally contoured nozzles

An overexpanded jet in a truncated ideally contoured nozzle is found to feature tonal behavior. The flow field investigated understand its origin and show how it modifies side-load properties. temporal spatial organization of wall pressure velocity are first experimentally characterized based on synchronized acquisition both wall-pressure along rings probes located within the high-rate time-resolved PIV fields measured plane section crossing downstream exit. external aerodynamics internal shown be clearly linked, but only at this frequency peak for which significant coherence emerges between azimuthal mode fluctuating field. A Delayed Detached Eddy Simulation carried out validated against experimental results order reproduce dynamics. analysis simulation data shows that behaviour indeed more largely felt whole structure where upstream propagating waves co-exist, even far possess support core have non negligible signature separated region. Spectral Proper Orthogonal Decomposition reveals nature intensity lateral forces directed by resonance related upstream- downstream-propagating coherent structures, imposes shock-waves network respond modulate levels surface.