Manufacture of flow optimized stiffener for improving rigidity of ducting

A method for the direct manufacture of aerospace cylindrical elements comprising:

• executing a single build run on a build chamber using direct fabrication technology to generate at least one cylindrical section, said at least one cylindrical section generated by:
• forming at least two partial cylinder segments within said build chamber during said single build run;
• forming a plurality of stiffening protrusions on each of said partial cylinder segments during said single build run and assembling said partial cylinder segments to form said cylindrical section, said cylindrical section having a cylindrical cross-sectional profile larger than a build chamber profile.

An aerospace duct element comprising:

• at least two partial cylinder duct segments formed during a single build run within a direct fabrication technology build chamber, said at least two partial cylinder duct segments orientated within said build chamber in a nested arrangement during said single build run, said at least two of said partial cylinder duct segments assembled to form a duct section, said duct section having a duct cross-sectional profile larger than a build chamber profile;
• said partial cylinder duct segments comprising a plurality of protrusions formed on an inner surface of said partial cylinder duct segments during said single build run, said plurality of protrusions stiffening said duct section and modifying flow through said duct section.