Ihi Corporation

Ishikawajima-Harima Heavy Industries Co., Ltd.

Ube Industries, Inc.

Japan Aerospace Exploration Agency

Gifu Plastic Industry Co., Ltd.

Tsutomu Oishi

Yoshinori Oba

Mitsuhiko Sato

Yoshizumi Tanaka

Nozomi Tanaka

Shinya Kusuda

Michiyuki Suzuki

Norifumi Miyamoto

Masahiro Hojo

Yoshiya Nakamura

Shingo Shibagaki

A sound-absorbing panel to be used affixed to a jet engine of an aircraft, provided with: a resin core layer having a first surface, a second surface disposed on the side opposite from the first surface, and multiple partitions extending between the first surface and second surface so as to partition multiple cells; a resin first skin layer laminated on the first surface of the core layer; and a resin second skin layer laminated on the second surface of the core layer. The first skin layer is disposed so as to face the external space while in use, and has multiple through-holes for providing communication between internal spaces of the multiple cells and external space faced by the first skin layer. The core layer has openings for providing communication between the internal spaces of the multiple cells and external space of the core layer.

Sound-absorbing panel and manufacturing method for same

A noise reduction system includes: a microjet ring () provided at an exhaust side peripheral edge of a main nozzle of a jet engine, and has a plurality of injection pipes () formed in a circumferential direction thereof at regular intervals; and a supply path configured to take part of compressed air in from a flow path in an upstream side of a combustor in the jet engine, and to guide the part of compressed air to the plurality of injection pipes (), wherein the plurality of injection pipes () is configured to inject the part of compressed air to a jet flow.

Noise reduction system

The present invention relates to a jet engine including protrusions () for preventing the increase of the velocity gradient of a fluid in a mixed layer of a jet flow and an external air flow by bending the mixed layer, when viewed from the side of a jet flow injected.

Jet flow nozzle and jet engine

A production process which comprises a preform formation step of forming a fiber preform made of silicon carbide short fibers having heat resistance of 1000&#xb0; C. or greater; a sol-gel preparation step of preparing a sol-gel solution containing a heat resistant compound having heat resistance of 1000&#xb0; C. or greater; an impregnation-drying-calcination step of impregnating the fiber preform with the sol-gel solution, followed by drying and calcining; and a crystallization step of crystallizing the fiber preform after impregnation, drying and calcination.

Fiber-reinforced heat-resistant sound-absorbing material and process for producing the same

A noise reducing device in a jet engine that has a cylindrical casing, a cylindrical partition wall that is inserted in the casing while protruding partially from a trailing edge of the casing, and a compressor that compresses air that is taken into the cylindrical partition wall, with the inside of the cylindrical partition wall serving as a duct in which a core stream of high-speed air flows, and the space between the cylindrical partition wall and the casing serving as a duct in which a bypass stream of low-speed air flows, and being connected with a wing of an airplane by a pylon that has a projection portion that extends beyond the casing to the downstream of the core stream and the bypass stream, the noise reducing device includes a nozzle, disposed at the pylon on the downstream of the core stream, that injects a fluid toward a noise generation source that is produced from the mutual approach of an ambient air stream that is produced outside of the bypass stream and the core stream.

Noise reducing device and jet propulsion system

A noise reduction system with a chamber includes a chamber () which is provided at a portion of a supply path connecting a flow path in an upstream side of a combustor in a jet engine to a plurality of microjet nozzles which is provided at an exhaust side peripheral edge of a main nozzle of the jet engine, wherein the supply path is configured to supply part of compressed air from the flow path into the chamber (), and the chamber () is configured to inject the compressed air through the plurality of the microjet nozzles () to a jet flow.

Noise reduction system with chamber

A jet flow discharge nozzle includes a tubular partition wall, a tubular casing which covers an outer periphery of the tubular partition wall, and a bifurcation which extends in an axial direction of the tubular partition wall and the casing so as to support downstream ends of the tubular partition wall and the casing from outside. Inside of the tubular partition wall is defined as a flow path for a high-speed core flow. A space between the tubular partition wall and the casing is defined as a flow path for a low-speed bypass flow. A pair of first projections is provided at a downstream edge of the tubular partition wall near the bifurcation at positions symmetric about the bifurcation. One of ridges of each of the first projections faces an upstream side. The invention reduces noise by avoiding adverse effects of the presence of the bifurcation on an increase in noise.

Jet flow discharge nozzle and jet engine

There is disclosed a lobe mixer comprising: a cylindrical partition wallwhich partitions a high-speed inner flow from a low-speed outer flow; a lobe portionwhich is disposed on a downstream side of the partition wall and whose transverse sectional shape is a waveform shape and is enlarged on the downstream side; and a connecting reinforcement memberwhich is disposed between lobe side wallsextending in a radial direction of the lobe portion to connect the adjacent lobe side walls to each other. The connecting reinforcement memberis a thin member disposed along a flow line of a fluid which flows between the lobe side walls.

Lobe mixer for jet flow

The porous sound-absorbing material manufactured is light and has excellent heat resistance to be applicable to the exhaust nozzle etc. of a jet engine, can effectively absorb noise as that from a jet engine, over a wide range of frequencies, is free from variations in porosity, and provides stable performance characteristics. An essential feature thereof is the formation of a skeleton of the material, with aggregates containing voids. Thus, a porous sound-absorbing material having a skeleton of aggregates with first voids is described, wherein diameters of first voids of the aggregates are 50 &#x3bc;m to 100 &#x3bc;m, approximately, and diameters of second voids between the aggregates are 100 &#x3bc;m to 600 &#x3bc;m.

Sound absorbing material and its manufacturing method

A lobe mixer ( ) used in jet engines, is provided with diameter expansion portions ( ) in which the diameters gradually increase in the downstream direction, in which adjacent diameter expansion portions have different diameters from each other, and which guide the core gasses that flow along the inner sides of the adjacent diameter expansion portions, peripherally outwards at different angles. Thus, the gasses are mixed without the thrust of the jet engine being reduced, and the noise of the jet is reduced.

Growing community of inventors

Tokyo, Japan

Tsutomu Oishi