Vibro-Acoustics Consortium


VAC Software

The development of software is not part of the mission of the VAC, but occasionally specialized software is needed for VAC projects. For example, it is sometimes necessary to translate from one data format to another in order to transfer data between two software products. Translation software is often written to facilitate data exchange

All VAC-developed software may be used by VAC members without charge.

ARIES is a program developed to analyze and design intake and exhaust systems for engines, compressors, and pumps. ARIES runs under MATLAB and is based on one-dimensional, transmission matrix theory. ARIES contains “elements” such as straight tubes, side branches, volumes, etc. for building up a complete system. The user may also specify the source properties, including source impedance, and the termination conditions of the system (i.e., flanged, unflanged, or anechoic). The output of ARIES includes the transmission loss of the system, the insertion loss, and the sound pressure response at the outlet or at any distance from the outlet, all as a function of frequency.

The VAC is also developing a numerical prediction program based on the Rayleigh Integral. This numerical prediction may be used for approximate calculation of sound radiated by vibrating structures and components. It is useful for making quick estimates of sound radiation.

Acoustic Material Measurements

Using the VAC materials characterization facility, we can measure the acoustical properties of sound absorbing materials according to ASTM E1050 and ISO test methods. This service is provided free-of-charge for VAC members and at a nominal cost to other companies.


We invite VAC member companies to send people to our facility to see first hand how noise prediction software may be used. This is done on an informal basis at mutually agreeable times