Vibro-Acoustic - SCS & Partners

SCS 902A - Experimental determination of acoustic properties of materials
The SCS 902A represents a complete set of devices and dedicated software, which is designed to cover all needs to characterize the acoustic properties of materials. Using a "common database" allows you to manage all measuring devices as a whole and make various measurements on a single sample or a set of samples of the same material. The results are available in both narrow-band and in 1/3 octave and stored so as to maintain a relatively short history development and quality control according to different parameters. Most of the devices are supported by hardware platforms commercially available (NI, DT, and other brands).

SCS 902A - Testing Devices
SCS 9020B - Kundt tube (impedance) - Satisfying Requirements of: ISO 10354-2, ASTM E-1050-12, for acoustic absorption, reflection, impedance Zs, admittance. 3 sizes available: 100 mm: 60-1200 Hz 28mm: 100-6400 Hz 45 mm: 80-4000 Hz
SCS 9020B/TL - Option for standard pipe (2 or 4 microphones) for sound insulation "TL" following ASTM E-2611-09, and complex impedance Zc, Bulk Modulus, Modal density.
SCS 9020B/T60 - Option to measure alpha, Zs, TL, Zech, Gamma, etc.. with the method Impulse Response.
SCS9020B-28s - Portable Impedance Tube for Porous Materials Sound Absorption and Insulation. SCS9020B-28S can be used with various DAQ devices and scientific software to manage impedance tube measurements (for absorption and/or for transmission) allowing full measurements features according to ISO 10354- 2, ASTM E-1050E-12, ASTM E-2611-09 - Download data sheet.
SCS 9021 - Oberst method for the determination of the elastic modulus and damping of fingers (ISO / DIN / ASTM) coated with damping materials. Excitation by electromagnetic transducers and measurement with accelerometer or laser sensor or proximitor.
SCS 9022 - SAE method for the determination of the damping factor of 6 mm thick steel plate suspended on 4 metal springs, coated with damping materials. Excitation by an instrumented hammer and accelerometer measurement of FRF.
SCS 9023 - Resistance to flow of porous materials (ISO Standrd) with forced air from the reciprocating motion of a piston that moves at a frequency of 2Hz. Internal pressure measured with a special microphone system, system calibration provided with airtight lid. scs902a_2
SCS 9025 - tortuosity with methodology based electrical impedance in water. The sample is placed in water between two electrodes. 9025-web
SCS 9026 - Module Bulk dynamic. Specific device for measuring static elastic modulus and Poisson's ratio, measuring the dynamic elastic modulus and damping of porous samples: textile and / or PU foam. The measurements may be carried out at atmospheric pressure within a vacuum chamber (100 mm Hg).
SCS 9031 - ABS Cabins for measuring the coefficient of assorbiento for random incidence (Sabine). Cabin with volume between 7:20 mc. scaled with respect to room ISO 354 200 cubic meters. Excitement through a set of speakers and measure 5 microphone positions, and using interrupted noise and Schroeder method, using the impulse response function.

SCS-9020B-LVDT Testing Software
The series software SCS902x have seen a constant improvement since about 20 years. Historically born in LabView and taken subsequently in the .NET environment, there have been few version also written in MatLab and LV, while latest new versions (LV series) use mainly LabView (MatLab, Maple, Java are still used for new developments and R&D matter). The software SCS-902x suite become more and more flexible and open, so we offer direct interface with physical modeling simulation software (check specific offer). Moreover, we are also able to offer data exchange and direct interface with other systems of measurement (software and hardware), from which we only need to get typical signal analysis functions as Gxx and H1; we also offer direct access via ActiveX, DLL, SDK, TCP-IP or other, or with reading files generated in txt format. Fully developed now to perform a real user friendly feature, SCS9020B-LVDT (Impedance tube software) takes automatically in account the perfect combination of tube diameters and microphones mutual distance, to optimize the "real" frequency range of measurement according to ISO 10534-2, ASTM E-1050, ASTM E-2611.

SCS 902A - Additional (optional) Devices
The systems SCS-902A can be supplied alone as the mechanical part, or together in bundles that include: microphones, preamps, cables, accelerometers, load cells, instrumented hammer single-point laser for measuring displacement planar laser beam for measurements of lateral deformations other transducers and accessories available depending on the specific measurement system.

SCS 9017 - In-Situ Experimental determination of acoustic properties of Noise Barriers and Road Surfaces
The SCS 9017 adopt "Adrienne" windowing and reflect the methodologies described by: Standard EN/TS 1793-1: Highway noise barriers acoustic performances Standard EN/TS 1793-2: Highway noise barriers acoustic performances Standard EN/TS 1793-3: Normalized road noise psectrum Standard EN/TS 1793-5: Intrinsical characteristics for in-situ airborne sound reflection and sound insulation Determination of Reflection Index R_i in 1/3 octave bands Determination of evaluation index D_RI Determination of Sound insulation index S_i in 1/3 octave bands Determination of evaluation index D_SI



SCS SCDT4 - Data Acquisition board
Data Acquisition System like NI or DT, 2 or 4 channels, with software libraries SP-DT (or equivalent) are suitable to provide data acquisition and calculation of necessary functions: Gxx, H1, etc. SCS SCDT4 is a special 4 channels version of DT board offered in SCS902A bundles.
Software application using libraries SP-DT (avaialble for every SCS-90xx system) act as a signal analysis engine, to support calcualtion of specific functions for the applications, but also as a General purpose SIgnal Analyzer up to 16 channels.

VIBRO-ACOUSTIC MATERIALS CHARACTERISTICS

DETERMINIG PORO-ACOUSTIC AND PORO-ELASTIC PROPERTIES OF ACOUSTIC MATERIALS

Technical Pubblications Download

The experimental determination with the SCS902A suite

Each parameter considered in physical models of materials as poro-acoustic and/or poro-elastic can be determined experimentally (Systems SCS 902A) or obtained by methods of matrix inversion (Matelys Software Rockcell).

Normal incidence (Impedance tube) sound absorption, Impedance, Admittance, Reflection coefficient, Transfer impedance, TL, Modal Density, Bulk Modulus, etc.
Flow Resistivity of Porous Materials
Tortuosity using electrical impedance method
Random Incidence statistical alpha coefficient in small scale Reverberation room
TL of scaled sample between reverberant and absorbing rooms, using ISO 3744(45) approach for Sound Power
Porosity measurement on request
Bulk elastic modulus using Force vibration; also measuring mechanical stifness and damping
Oberst method for damping materials measurements
SAE Plate for damping materials measurement

The experimental determination of one or more of the individual parameters significantly improves the results of the simulation.

Physical models simulation

Are implemented both simple models (one parameter) and type advanced (up to eight parameters) to describe the characteristics of porous materials:

Delany-Bazley (1 parameter)
Johnson-Champoux-Allard (5 parameters),
Johnson-Champoux-Allard-Pride-Lafarge (8 parameters),
Olny Boutin double-porosity model, surface micro-perforated with circular holes, slits or rectangular,
Biot Model (isotropic internal structure with 4 parameters) applicable to all previous models to include the effects of the elastic structure.

Acoustic test on Noise Barriers

ADRIENNE windowing for ISO EN 1793