Structural and/or acoustic panel of a nacelle of an aircraft propulsion assembly and related manufacturing method

A panel for a nacelle of an aircraft propulsion assembly, comprising:

• two skins;
• a cellular structure between the two skins, the cellular structure comprising transverse partition walls delimiting cells;
• fibrous folds each comprising:
• a first peripheral portion extending along one of the two skins,
• a pair of central portions extending transversely from opposing ends of the first peripheral portion so as to form at least one portion of a pair of the transverse partition walls, the pair of the transverse partition walls defining the same one of the cells, the pair of central portions having ends disposed at the other one of the skins, and
• a pair of second peripheral portions extending from the ends of the pair of transverse partition walls toward each other and along the other one of the two skins, the pair of second peripheral portions being spaced apart from each other on the other one of the skins,
• wherein at least some of the fibrous folds are integrally manufactured as a continuous structure during manufacturing of the fibrous folds such that the first and second peripheral portions of the at least some of the fibrous folds are continuously formed to define a plurality of openings corresponding to respective ones of the cells,
• wherein the first peripheral portion has a main surface extending laterally from the pair of central portions and extending along and parallel to the one of the two skins and the pair of second peripheral portions each have a main surface extending laterally from one of the pair of central portions and extending along and parallel to the other one of the two skins.