Experimental and numerical study of rotor aeroacoustics

Abstract

The work documents recent experiments at the Kazan National Research Technical University named after A.N. Tupolev (KNRTU-KAI), related to helicopter acoustics. The objective is to measure near-field acoustics of rotors in hover and provide data suitable for CFD validation. The obtained set of data corresponds to a Mach-scaled rotor of known planform and the results are of high resolution. An advantage of the current dataset is that direct near-field acoustic data is made available and this allows for easy and direct comparisons with CFD predictions, without the need to use far-field aeroacoustic methods. Nomenclature

Modelling of Flow Characteristics of Main Rotor with Elliptical Root Section in Hover Mode

“…The results of numerical modeling are compared to the experimental data at the rotational speed of 900 rpm for the observer (microphone) located on the plane of rotation at the distance of 1.2R away from the rotational axis. Reference [9] contains additional cases, where the observer is located lower and higher relative to the rotor's plane of rotation. Figure 5 and the results of reference [7] suggest that agreement between numerical modeling results and experimental data is achieved for R1 rotor at the rotational speed of 900 rpm.…”