Comparison of wavepacket models for supersonic twin jets against near-field pressure measurements

Resumen

Plane-marching PSE wavepackets for a supersonic twin-jet operating at perfectly-expanded conditions are compared against near-field pressure measurements with the purpose of validating the modelling strategy. Two streamwise phased-microphone arrays distributed close to the external mixing-layer boundary of each jet are employed to obtain pressure measurements in the linear hydrodynamic fluctuation region. PM-PSE calculations are performed for the symmetric toroidal mode (mode SS0) based on a tailored twin-jet mean flow constructed via an analytical profile fitted from PIV measurements. Comparisons of the amplitude evolution in the streamwise direction for different frequencies reveal a very remarkable agreement between the SS0 PSE prediction and the symmetry-decomposed pressure signals, particularly when SPOD-filtered experimental measurements are considered. These results constitute a new validation of PM-PSE for modelling twin-jet wavepackets related to mixing noise.