New Controllable Sound Absorbers Made of Vacuum Packed Particles - New Contributions in Information Systems and Technologies - page 284

Table 1. Massesofdifferentgranularmediaandthecontainerusedforacousticresearch

MaterialsymbolMass[g]
PP 65,6
PS 76,9
POL 90,5
ABS 78,3
Containermass 73,4

Fig. 2. Photographyofgranularmaterialsusedforexperiments

All research was performed in the Vibroacoustic Laboratory of the Faculty
ofAutomotiveandConstructionMachineryEngineeringintheWarsawUniver-
sity of Technology. The test stand (fig. 3) consisted mainly of Br¨uxel & Kjær
equipment, which includes an impedance tube of type 4206, two 1

/

4inchmi-
crophones2670,agenerator3160-A-04/2andamplifier 2716C.Additionally, a
vacuumpumpAgaLaborPL2andtwopressuregauges(measurementclass2,5
and1,6)wereused.TheexperimentwascontrolledbyacomputerwithPulseLab
Shop(acousticmaterialtesting)software.Testswereheldinanairconditioned
roomwithconstanttemperatureandhumidity.

Fig. 3. Maincomponentsofteststand