blattprofil a mantelluftschraube.

摘要

Profile (1) for a shrouded aerial propellor blade, the relative thickness of which is between 9% and 15%. …??According to the invention, the curvature of said profile has a maximum value at the leading edge (A) of the latter, and the suction line (2) comprises three successive portions (2.1, 2.2 and 2.3), such that… - in the first portion (2.1), the curvature decreases rapidly from said maximum value at the leading edge to a value in the neighbourhood of 20 at a first point (B), the reduced abscissa of which is in the neighbourhood of 1%;… - in the second portion (2.2), the curvature decreases more slowly from said value in the neighbourhood of 20 at said first point (B) to a value in the neighbourhood of 1 at a second point (D), the reduced abscissa of which is in the neighbourhood of 25%; and… - in the third portion (2.3), the curvature is less than 1 between said second point (D) and said trailing edge (C). …IMAGE…