FIELD: metrology.
SUBSTANCE: invention relates to the metrology, in particular to the noise absorbing panels quality assessment methods. Test chamber walls are lined with the noise-absorbing lining under investigation in the form of sound-absorbing panels, the noise source is placed on the floating floor, under which the vibration-damping panel is installed, designed to eliminate interference during the noise-absorbing panels testing. Measurement points with the turned on noise source are fixed on the measuring surface, which is a spherical surface surrounding the noise source. Then determining the sound power level, the adjusted sound power level, the sound pressure level decrease value. Cladding noise-absorbing panel is made containing the smooth and perforated surfaces, between which a combined sound-absorbing layer is placed, which is an alternation of solid sections and hollow sections. Hollow areas are formed by prismatic surfaces having a parallelogram shape in cross section, the inner surfaces of which have a jagged structure. Tops of the teeth face inside the prismatic surfaces, and the edges of the prismatic surfaces are fixed respectively on the smooth and perforated walls. Cavities of the hollow sections, formed by prismatic surfaces, are filled with a sound absorber, and between the smooth surface and continuous sections of the layer of sound-absorbing material of complex shape, as well as between the perforated surface and solid sections, there are resonant plates with resonant inserts performing the functions of the neck of Helmholtz resonators. Inside the hollow sections, the internal surfaces of which have a dentate structure, there are additional resonance elements made in the form of spherical shells, inner surface of which is connected by resonant inserts with cavities located between the perforated surface and the solid sections of the sound-absorbing element.
EFFECT: expansion in the having several elastic connections with the object body parts testing objects and the cladding combined noise absorbing elements technological capabilities.
1 cl, 3 dwg
