Simulations of whistling and the whistling potentiality of an in-duct orifice with linear aeroacoustics

• This paper demonstrates a linear aeroacoustic simulation methodology to predict the whistling of an orifice plate in a flow duct. The methodology is based on a linearized Navier-Stokes solver in the frequency domain with the mean flow field taken from a Reynolds-Averaged Navier-Stokes (RANS) solution. The whistling potentiality is investigated via an acoustic energy balance for the in-duct element and good agreement with experimental data is shown. A Nyquist stability criterion based on the simulation data was applied to predict whistling of the orifice when placed in a finite sized duct and experiments were carried out to validate the predictions. The results indicate that although whistling is a non-linear phenomena caused by an acoustic-flow instability feed-back loop, the linearized Navier-Stokes equations can be used to predict both whistling potentiality and a duct system’s ability to whistle or not.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Strömningsmekanik och akustik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Fluid Mechanics and Acoustics (hsv//eng)

Keyword

aeroacoustics

frequency-domain

linearized Navier-Stokes

scattering

duct

Acoustics

Akustik

Publication and Content Type

ref (subject category)

art (subject category)