Compressible Boundary Data Immersion Method Applied to Force and Noise in Turbulence-Ingesting Rotors

Numerical simulations were conducted on a 10-blade Sevik rotor ingesting wake downstream of two turbulence-generating grids. These simulations were based on implicit large-eddy simulation (ILES) and the boundary data immersion method (BDIM) for compressible flows, which were solved using a fully self-programmed Fortran code. Results show that the predicted thrust spectrum aligns closely with the experimental measurements. In addition, it captures the thrust dipole directivity of the noise around the rotating propeller due to random pressure pulsations on the blades, as well as the flow structures simultaneously. Furthermore, the differences in the statistical characteristics, flow structures, and low-frequency broadband thrust spectra due to different turbulence levels were investigated. This analysis indicates that the interaction between the upstream, which is characterized by a lower turbulence level and a higher turbulent length of scale, and the rotating propeller results in a lower amplitude in force spectra and a slight increase in the scale of tip vortices.