Sound reducer

A sound reducer, called a reducer, comprising:

• an inlet opening for gases, called gases, intended to propagate in the sound reducer;
• an expansion chamber and a channel communicating with said expansion chamber and extending, along an axis, called channel axis, from the expansion chamber to an outlet opening for the gases from the reducer;
• an axis of revolution of the reducer inlet opening and an axis of revolution of the reducer outlet opening are parallel to the channel axis;
• the reducer further comprises an absorption zone for a sound wave produced by the gases, said absorption zone enveloping, at least in part, said channel;
• the sound wave absorption zone is constituted, at least in part, by a one-piece architectured material and is arranged so that a part of the gases flow from the channel through the architectured material to an outer wall of the architectured material delimiting the absorption zone;
• the one-piece architectured material comprises a set of elementary patterns, called patterns, forming the one-piece structure of the architectured material, at least some of the patterns:
• are closed and delimited by a wall forming a cavity;
• and
• comprise at least two openings through which the cavity of each of the patterns of the at least one part of the patterns communicates with the outside of the cavity of each of the patterns of the at least one part of the patterns.