CD-adapco Claims First in Aeroacoustic Noise Reduction
YORK, LONDON and STUTTGART, July 13, 2010 - The reduction of aerodynamic
noise has long been a design concern throughout the automotive, rail and
aerospace industries. Exposure to extraneous noise generated by acoustically
non-optimal designs not only detracts from ride enjoyment, but also
contributes significantly to driver fatigue.
CD-adapco, the world’s
leading supplier of engineering simulation solutions to the automotive industry,
has demonstrated a first in fluid-structures integrated capability for
aeroacoustics simulations with structural impedance effects. CD-adapco is
collaborating with the Aeroacoustics Working Group of German automotive
manufacturers, which has issued the following statement:
“The consortium of the German automotive manufacturers Audi, BMW, Daimler,
Porsche and Volkswagen, that cooperates for improved numerical aeroacoustic
tools, considers the results of the structural impedance effects using the
coupled Finite Volume flow and stress analysis to be a well conceived and
practical solution and encourages CD-adapco to continue validation against the
performance data which has been made available in this project.”
CD-adapco's flagship software, STAR-CCM+, is unique in its ability to perform
fully coupled fluid-solid interaction. It uses a finite volume solid
stress solver implicitly integrated with the finite volume flow solver to
analyze the acoustical damping effects of flexible materials.
A particularly pernicious source of noise is that associated with sunroof (or
side-window) buffeting, which is caused by unsteady flow over the sunroof
opening interacting with the roof panel, and radiating sound to the vehicle
occupants. STAR-CCM+ has been extensively compared with sunroof buffeting
measurements on the industry standard SAE-body, modified to include a sunroof
cavity with different roof materials – including Aluminum, Perspex and Plywood.
The simulations correctly predicted that the noise level which the driver hears
can be reduced by to 10dB (decibels) at the peak frequency, illustrating how the
flexibility of the roof panel is able to absorb acoustical energy to quiet the
The simulation results showed how the flow becomes unsteady behind the
leading edge of the sunroof opening, creating a vortex which travels downstream
and impacts the rear roof panel behind the sunroof opening. One way to design
against this phenomenon is to add deflectors to change the flow pattern over the
opening, often by introducing additional mechanical parts. By changing the
acoustic properties of the car panels, similar noise reductions can be achieved.
By working closely with car manufacturers, CD-adapco provides validated tools
to predict and design against wind-induced noise early in the design process,
resulting in more refined vehicles that are more comfortable and ultimately
safer to drive.
For more information, visit
If news like this is important to you,
sign up for TenLinks Daily, our free
CD adapco website
Products and Companies list- by
Source: Material used in press releases is often supplied by external
sources and used as is.