Turboshaft engines can become the main source of helicopter noise at takeoff. Inlet radiation
mainly comes from the compressor tones, but aft radiation is more intricate: turbine tones …

A couple of new mode detection methods are proposed in this paper to enable effective and
efficient radial mode analysis of in-duct tonal sound fields by utilizing compressive sensing …

This paper addresses the problem of in situ calibration of a pin hole-mounted microphone
array for in-duct acoustic measurements. One approach is to individually measure the …

This paper presents a methodology to estimate the fan modal content based on in-duct
acoustic measurements. These measurements were performed on a 20” UHBR fan rig …

A novel technique is presented, which combines the fields of coherence-based noise-source
identification with acoustic modal analysis. Coherence-based noise-source-identification …

This paper describes the interior acoustic pressure of a cylindrical cavity driven by a shear
layer. Existing cavity flow literature is generally focused on rectangular cavities, where the …

The present work addresses the interaction noise of a small-size rotor-stator fan with
heterogeneous Outlet-Guide-Vanes using the Lattice-Boltzmann Method. Three different …