Disclosed is a muffler for a water-cooled chiller or air-cooled of a vapor-compression or absorption refrigeration system, the muffler having: an upstream case (110) having a fluid inlet (120); a downstream case (115) connected to the upstream case at a downstream end of the upstream case, the downstream case having a fluid outlet (125); the upstream case having a plurality of axially adjacent outer muffler rings (145) and a plurality of axially adjacent inner muffler rings (155), the outer muffler rings being axially coextensive and a radially exterior to the inner muffler rings and defining a fluid inlet passage (140) therebetween, wherein the outer muffler rings and inner muffler rings are a metal mesh material.

A helical strake pole system that includes a tubular pole having a longitudinal axis and threaded attachment points. The system further includes a helical strake fin disposed circumferentially around a portion of the tubular pole along the longitudinal axis. The system further includes couplers disposed on the tubular pole. The couplers are configured such that each coupler has a first portion with a slot configured to receive an upper portion of the helical strake fin and a second portion configured to removably coupled to a threaded attachment point of the tubular pole. In addition, each coupler is configured to position a portion of the helical strake fin substantially perpendicular to a surface of the tubular pole.

Spacer for a hose or pipeline, comprising a spacing pipe that is fitted around the hose or pipeline during normal use, wherein the spacing pipe is slit in the lengthwise direction, and wherein the spacing pipe is constructed in segments, and wherein the segments are connected to each other in articulated manner, wherein the segments assigned to the slit are finished with locking elements.

The present disclosure relates to a structure and method of reducing refrigerator noise incident to a compressor failure. More particularly, the present disclosure relates to a structure and method of reducing refrigerator noise which is likely to occur due to collision of pipes or the like with surrounding structures when a compressor installed inside a refrigerator machine room stops operating. The noise preventing/reducing structure includes a support member protruding from a wall surface or a bottom surface of the refrigerator machine room and a protective member configured to surround at least a part of a pipe installed in the refrigerator machine room. The support member comprises: a cavity having one side open; a seating surface disposed in the cavity and configured to support the protective member seated thereon; and a raised portion protruding from the seating surface.

Described herein are noise attenuating ducts and vehicles using these ducts for environmental control systems. A duct comprises an exoskeleton structure and a sound-absorbing structure, disposed within and conforming to the exoskeleton structure. The exoskeleton structure provides external mechanical support to the sound-absorbing structure thereby helping to maintain the tubular shape of the sound-absorbing structure. This external support does not interfere with the airflow inside the sound-absorbing structure. Furthermore, the external positioning of the exoskeleton structure allows the integration of various support mounting features for the installation of the duct in a vehicle. In some examples, the exoskeleton structure comprises a plurality of enclosed openings to reduce the weight of the exoskeleton structure and provide additional flexibility. Furthermore, additive manufacturing of the exoskeleton structure allows achieving a monolithic structure with various features and characteristics described above.

The main subject matter of the invention is a ventilation device including at least one duct intended to channel an air flow in an air flow direction inside the duct, the ventilation device including at least one acoustic attenuation member at least partially arranged around the duct and made up of a network of resonators, each resonator having at least one cavity and one neck connecting the cavity to the duct, the resonators that make up the network of resonators being distributed at least parallel to the air flow direction. A distance separating two necks varies along a direction parallel to the air flow direction and in that a volume of the cavities varies along the direction parallel to the air flow direction.

Disclosed is a muffler for a water-cooled chiller or air-cooled of a vapor-compression or absorption refrigeration system, the muffler having: an upstream case having a fluid inlet; a downstream case connected to the upstream case at a downstream end of the upstream case, the downstream case having a fluid outlet; the upstream case having a plurality of axially adjacent outer muffler rings and a plurality of axially adjacent inner muffler rings, the outer muffler rings being axially coextensive and a radially exterior to the inner muffler rings and defining a fluid inlet passage therebetween, wherein the outer muffler rings and inner muffler rings are a metal mesh material.

A vibration damper (1) operating in accordance with the mass-spring principle, which is provided for fitting on an injection line pipe, includes a main body (2) which comprises an elastomeric vibration-damping material and has an inside hollow space (3) which passes therethrough in the longitudinal direction and which in the fitted condition surrounds the injection line pipe, the longitudinal axis (4) of the inside hollow space (3) coinciding with the longitudinal axis of the pipe, and is characterized in that it has a mass distribution eccentric with respect to its longitudinal axis (4) and can be non-rotatably fitted on the injection line pipe.

Spacer for a hose or pipeline, comprising a spacing pipe that is fitted around the hose or pipeline during normal use, wherein the spacing pipe is slit in the lengthwise direction, and wherein the spacing pipe is constructed in segments, and wherein the segments are connected to each other in articulated manner, wherein the segments assigned to the slit are finished with locking elements.

A vibration damper for a fuel conduit of a gas turbine combustor includes a mounting portion and a damping portion. The mounting portion is secured to the fuel conduit, and the damping portion includes a stack of damping washers, a bushing on top of the stack of damping washers, a spring clip secured around the stack of damping washers and the bushing, and a shoulder bolt disposed through the bushing and the stack of damping washers and engaged to the mounting portion.