Fluid duct

A fluid duct 2 comprising a tubular base wall 11 surrounding a duct channel and at least one bellows 10 formed along a section of the tubular base wall 11, the bellows 10 comprising a plurality of convolutes 12 having a profile 14 projecting radially from the tubular base wall 11, wherein at least one of said plurality of convolutes 12 wraps around the duct channel with a wrap-around angle Ω of between 180° and 720° measured from a first end 22a to a second end 22b, the vertex of the wrap-around angle Ω at the center line C, said second end 22b being offset in a flow direction F parallel to a centerline C of the duct channel by a non-zero offset distance D from the first end.