Abstract: A silencer with a casing and at least one inlet passage for leading gas into said casing, and at least one outlet opening for leading gas out of said casing, said silencer containing at least one acoustic chamber contained in the casing, at least one porous body inside said chamber, the porous body comprising a through-flow filter occupying at least part of the chamber, where said at least one porous body is designed to retain particles contained in the gas, at least one connecting passage for leading gas from each one of the at least one acoustic chamber to another of the at least one acoustic chamber or to an exterior environment or an exterior chamber, wherein at least part of at least one of said connecting passages extends along an outer surface of the porous body, so as to lead gas along a helical flow path.

Abstract: The invention relates to an apparatus arranged within a gas flow system, said apparatus comprising a matrix structure composed of a plurality of solid elements being arranged singularly or in groups. The gas flow system comprises a plurality of voids in-between said solid elements. The matrix structure allows gas to propagate within said matrix structure, and the matrix structure is intended for changing the chemical composition of said gas having passed through the system. The change in chemical composition either takes place during one or more of the following processes: one or more chemical reactions promoted by catalytic coating of said elements, promoted mixing of different phases of components of said gas, or phase change by fluid drops evaporating or solid particles changing phase, or takes place by the matrix structure having a degree of open structure of said matrix structure for allowing the gas to flow along an overall flow pattern being a not-truly 3-dimensional flow pattern.

Abstract: The invention relates to a silencer being designed with sound absorptive material (13, 23) and a conduit section (1, 2) with one or more conduits (1) for leading gas flow into the silencer and with one or more outlets (2) for leading gas form the silencer. The sound absorptive material (13, 23) and the conduit section (1, 2) constitutes a protrusion extending from part of an outer shell (4) such as from an end cap (5, 6) constituting part of the shell for the silencer, or from an internal member, such as a baffle (9, 10) possibly separating at least two through-flowed chamber (12) of the silencer. Not-through-flowed cavities (17, 27) are arranged essentially adjacent to or at least partly surrounding said sound absorptive material (13, 23), thereby constituting one or more resonators acoustically communicating with said at least one through-flowed chamber. The silencer may also be designed so as to act as a spark-arrestor. Also, the invention relates to a combustion engine provided with such silencer.

Abstract: A silencer that comprises a casing, one or more pipes or passages leading a flow of gas to the casing and a device for leading gas from the casing. The silencer further has at least one internal chamber, one or more flow inlets to the chamber and one or more flow outlets from the chamber, and one or more flow distributing devices connected to the flow inlet(s) and/or to the flow outlet(s). The flow distributing device comprises one or more walls or profiles extending on a geometrical surface that defines a boundary between an inner volume of the flow distributing device and the chamber. The silencer further has one or more apertures for a flow of gas through the apertures and for leading gas either out of the inner volume into the chamber, or into the inner volume from the chamber. The apertures have a smallest cross-sectional transverse dimension s and a length L, the dimension s being at the maximum 0.2 times the smallest cross-sectional dimension D of the inlet or outlet.

Abstract: A silencer with a casing and at least one inlet passage for leading gas into said casing, and at least one outlet opening for leading gas out of said casing, said silencer containing at least one acoustic chamber contained in the casing, at least one porous body inside said chamber, the porous body comprising a through-flow filter occupying at least part of the chamber, where said at least one porous body is designed to retain particles contained in the gas, at least one connecting passage for leading gas from each one of the at least one acoustic chamber to another of the at least one acoustic chamber or to an exterior environment or an exterior chamber, wherein at least part of at least one of said connecting passages extends along an outer surface of the porous body, so as to lead gas along a helical flow path.

Abstract: A silencer for silencing and also for filtering exhaust gases, contains at least one acoustic resonator chamber (13, 14, 15, 16) (Helmholtz frequency), at least one porous body (7, 8) the porous body (7, 8) occupying at least part of the chamber and at least one connecting passage (17) for leading gas from each one of the acoustic chamber wherein the connecting passage (17) extend along the outher surface of the porous body, so as to lead along a helical flow path (19).

Abstract: A silencer for silencing and also for filtering exhaust gases, contains at least one acoustic resonator chamber (13, 14, 15, 16) (Helmholtz frequency), at least one porous body (7, 8) the porous body (7, 8) occupying at least part of the chamber and at least one connecting passage (17) for leading gas from each one of the acoustic chamber wherein the connecting passage (17) extend along the outher surface of the porous body, so as to lead along a helical flow path (19).

Abstract: A device for silencing a flow includes at least one acoustic chamber through-flowed by gas, e.g., exhaust gas, at least one inlet pipe and at least one pipe or passage interconnecting two chambers or a chamber and an exterior environment or chamber and is designed with such cross-sectional area transitions, between passages and the chambers that the sound attenuation achieved by the device is high while the pressure drop across the silencer is low and that high attenuation at low characteristic frequencies of flow systems are obtained. The device may contain at least one of diffusers, monolithic bodies and catalysts. The passages may be curved or helical so as to allow for a low natural frequency. Embodiments with resonance chambers attenuating at selected frequencies are disclosed. A method for operating a vehicle including a combustion engine and a silencing system is disclosed.

Abstract: A device (a silencer) for silencing a flow of gas, such as an exhaust gas, comprises at least one acoustic chamber (1, 2, 3) through-flowed by gas, at least one inlet pipe (6) for leading gas into the device and at least one pipe or passage (4, 12, 13) interconnecting two chambers or a chamber and an exterior environment or chamber and is designed with such features, including such cross-sectional area transitions between pipes or passages (4, 6, 12, 13) and the chambers (1, 2, 3) that the sound attenuation achieved by the device is high while the pressure drop across the silencer is low and that high attenuation at low characteristic frequencies of flow systems comprising the device are obtained. One or more diffusers (10a, 12a, 13a) for diffusing at least part of the gas flow, e.g., at the inlet to the chambers may be comprised in the device. One or more monolithic bodies or catalyzers may be comprised in the device. Devices with curved or helical passages (FIG.

Abstract: A system for providing cooling incorporates a combustion engine (1, 2) equipped with an exhaust heat recovering heat exchanger (3) which is adapted to transfer heat energy to a heat-driven chiller (4) in which cooling can be extracted from one or more heat carrier circuits (8). The cooling thereby provided may be used for cooling of engine charge air or compressor air and/or for providing cooled air for human comfort and/or for goods. Use of heat energy derived from the engine exhaust gas flow can be added to the system. Exhaust or air intake heat exchangers may provide silencing or gas cleaning of air or gas. The system may, e.g., be applied to vehicles. Compact absorption chillers may be used in the system. A method for providing cooling is disclosed.

Abstract: A silencer, for silencing and purification of exhaust gases, comprises an air-tight casing (1) connected to an exhaust inlet pipe (2) and to an exhaust outlet pipe (3) and contains at least two acoustic compartments (4i, 4ii) and one or more monolithic bodies (5) such as catalysers or particle filters through which exhaust gases flow in a flow direction in longitudinal channels or porosities, and one or more pipes or channels (6, 7), at least one pipe or channel penetrating one or more of the monolithic bodies (5) and guiding exhaust gases in a flow direction which is opposite to the flow direction in the channels or porosities of the monolithic body (5), and at least one of the pipes or channels (6, 7) connecting the at least two acoustic compartments (4i, 4ii). The general flow direction is preferably reversed substantially immediately upstream of a penetrated monolithic body (5) and substantially immediately downstream of either the same monolithic body (5) or of another penetrated monolithic body.

Abstract: Silencer with built-in catalyser which utilises a given total space optimally for simultaneous sound attenuation and catalytic treatment of gases, e.g. exhaust gases from internal combustion engine. The silencer with built-in catalyser comprises a casing (1) connected to an inlet pipe (2) and to an outlet pipe (3), a sound attenuation compartment (4), a downstream catalytic body (5), a flow-area widening diffuser element (6) extending from the inlet pipe and contained within the compartment, and a cross-plate (7) which is positioned between the diffuser element and the catalytic body and from which the flow is distributed evenly across the inlet to the catalytic body. At least two openings (8) are provided between the diffuser element and the catalytic body, at least one such opening (9) providing a communication to the sound attenuation compartment and at least two such openings (10) being pervaded by gas flows.

Abstract: An apparatus for silencing and catalytic treatment of gases has an air-tight casing connected to an exhaust inlet pipe and to an exhaust outlet pipe, acoustic compartments, monolithic bodies, and a diffuser element. The diffuser element is connected to the inlet pipe, or further downstream within the casing. The diffuser element distributes the gases evenly across the inlet face of the monolithic bodies. The diffuser element is a guide baffle or plate and a juxtaposed stagnation baffle or plate, which causes both flow stagnation in front of the stagnation plate and the gases to flow radially within the diffuser element. The diffuser element has apertures which are pervaded by partial flows of the gas and are adapted to provide additional recovery in the gas flow passing through the diffuser element. The geometry defining the fluid flow field within the diffuser is designed to prevent flow separation from the contour walls of the diffuser.