指耕作 发表于 2025-3-26 21:18:00
https://doi.org/10.1057/9781403946041d consulting engineers and architects to design current state-of-the-art noise control and room acoustic measures. Special emphasis is on damping at low frequencies and using fiber-free absorbers with smooth closed surfaces, innovative tools and devices to solve acute acoustical problems.高深莫测 发表于 2025-3-27 03:41:29
Helmut V. FuchsFundamentals of and recent advances in noise control and room acoustic design.Description and application of innovative absorbers and silencers.Applications and demonstrations of innovative concepts i单调性 发表于 2025-3-27 08:30:19
http://image.papertrans.cn/a/image/159617.jpg价值在贬值 发表于 2025-3-27 12:21:28
Introduction,lations having reduced emission power levels L. of passenger cars, motorcycles and trucks in Europe on average 6, 9, respectively 12 dB(A) in the last 20 years. The decisive . is rising particularly due to surging traffic on an increasingly denser grid of streets, roads and highways. Noise disturbanFISC 发表于 2025-3-27 15:27:42
Sound Absorption for Noise Control and Room-Acoustical Design,ared to its wavelength l, it is partially reflected (P.) (and possibly diffracted and scattered), allowed to pass through (P.), transmitted as structure-borne sound (P.), as well as absorbed (P.), see Fig. 3.1.GRAZE 发表于 2025-3-27 19:42:15
Panel Absorbers,ive absorbers. Due to their market dominance, they also predominate in all the standard literature on absorbers and silencers. When combined with conventional foil facings as air-tight protective layers against abrasion, their mass should not exceed a certain limit according to Eq. (.) in order to ioverweight 发表于 2025-3-28 00:48:41
Helmholtz Resonators,acoustic damping material. Here the effective plate thickness t., respectively the perforation ratio s according to Eq. (.) should not exceed, respectively fall short of certain limits in order to hinder sound as little as possible from entering the actual absorber, e.g. a porous layer. On the otherObvious 发表于 2025-3-28 05:55:40
http://reply.papertrans.cn/16/1597/159617/159617_38.pngEngulf 发表于 2025-3-28 06:53:20
Absorbers with Active Components,iness. The compound panel resonators of Sect. 5.3, the membrane absorbers of Sect. 6.3 and the tubular silencers of Sect. 7.3 represent new fiberless variants with particularly high, broadband effectiveness at low frequencies. “Active noise abatement” measures, also called “anti-noise”, neverthelessMorbid 发表于 2025-3-28 13:43:26
Microperforated Absorbers,aterials with passive, i.e. non-reactive behavior toward airborne sound waves. More recently, various types of absorbers gain importance which react quite differently to the sound field that excites them (Chaps. .–.). Whether the vibrations occur in panels, foils or membranes (Chaps. . and .) or in