An example fluid system can include a fluid noise suppressor having a resilient insert having an outer surface; wherein the resilient insert can be operable to dampen a fluctuation of a total pressure about a mean static pressure, providing effective noise reduction that without the resilient insert, would have occurred in the flowing fluid with the fluctuation; and wherein the mean static pressure can be between about 100 psig to about 10,000 psig.

A pipe with a sound absorber has a fluid pipe in which fluid passes and a sound absorber of a pulp-based fiber material. The sound absorber surrounds an outer circumference of the fluid pipe. The sound absorber is provided to secure space between an outer surface of the fluid pipe and an inner surface of the sound absorber.

The present disclosure provides a laminated structure with a through hollow structure having heat insulation, a light weight, durability, and sound absorption performance to reduce wind noise, transmitted noise, and the like. The laminated structure of the present disclosure has a foamed resin layer having continuous pores containing fused resin foam particles, and an air-impermeable outer layer provided on one side of the foamed resin layer, where a part of the foamed resin layer of the laminated structure cut out with a diameter of 41.5 mmϕ has an amount of air permeability of 2.5 cm.sup.3/(cm.sup.2.Math.s) to 40 cm.sup.3/(cm.sup.2.Math.s) measured by the Frazier method in which the foamed resin layer is set as an air introduction side.

Compact sound attenuation systems for fluid ducts are provided having one or more sound attenuation units that can be absorptive or reflective, depending on design. Each sound attenuation unit has one or more encircling Helmholtz resonators that fully encircle the duct in a lateral direction. Sound attenuation units can be coincident with the duct well and either interior or exterior to the duct, or in some instances can be partly interior and partly exterior to the duct. Sound attenuation systems can be tuned for maximum attenuation of a single resonance frequency, or can include multiple units of different frequencies for broadband attenuation.

A sound attenuator has an inner pipe (12) with expansion sections (121) of enlarged diameter corresponding to the constriction sections (141) of an outer pipe (14). The expansion sections (121) in pairs axially delimit an intermediate inner pipe section (122) containing a wall opening (18) and having a reduced diameter relative to the expansion sections (121). The inner surface of the outer pipe (14) in each of its constriction sections (141) is connected to the outer surface of the inner pipe (12) in its respective corresponding expansion section (121). A method of manufacturing such a sound attenuator (10) also is provided and uses internal high-pressure forming.

Provided are conduits for air flow that are capable of reducing noise and related methods. The provided conduits include a first section that is tubular and substantially non-perforated and a second section with at least a portion having a multiplicity of microperforations that provide an average flow resistance of from 50 MKS Rayls to 8000 MKS Rayls therethrough. The second section is either (a) tubular and connected in series with the first section, with an outer surface of the second section being in fluid communication with an outer surface of the conduit, or (b) disposed within the first section.

A method is disclosed for making a duct assembly including an internal component part such as a silencer is disclosed. The duct assembly may be made in a blow-molding operation in which first and second duct parts are formed from a single parison as a combined part that is then split apart to receive a component part in a housing and subsequently closed by a closure part. Alternatively, the first and second housing parts may be separately formed and a component part may be inserted into a housing defined by one or both of the first and second duct parts. The first and second duct parts may be joined and sealed by injection molding a ring over telescopically assembled ends of the first and second parts.

A method is disclosed for making a duct assembly including an internal component part such as a silencer is disclosed. The duct assembly may be made in a blow-molding operation in which first and second duct parts are formed from a single parison as a combined part that is then split apart to receive a component part in a housing and subsequently closed by a closure part. Alternatively, the first and second housing parts may be separately formed and a component part may be inserted into a housing defined by one or both of the first and second duct parts. The first and second duct parts may be joined and sealed by injection molding a ring over telescopically assembled ends of the first and second parts.

Described herein is a smoke and sound barrier for construction assemblies comprising a penetration wherein, optionally a packing material, and a non-porous adhesive article are used.

A soundproof structure body includes a first tube structure and a second tube structure connected to the first tube structure and having a cross-sectional area different from the first tube structure, in which a structure body having a cross-sectional area smaller than a cross-sectional area of the first tube structure is installed in the first tube structure, and a transmission loss in a case where the structure body is installed in the first tube structure with respect to a case where the structure body is not installed in the first tube structure is positive at two frequencies adjacent to each other and difficult to generate an air column resonance mode in the first tube structure. This soundproof structure body generates a soundproof effect even at frequencies other than air column resonance of a tube structure such as a duct or a muffler, has a small size, and can obtain a high transmission loss in a wide-band.