Masking bladed disc for reducing the radar signature of a moving compressor moving disc of a jet engine

A bladed wheel for masking a moving wheel of a turbojet engine, comprising:

• vanes, each vane including a lower surface wall and an upper surface wall joined at a leading edge and at a trailing edge and extending along a span axis from a root to a tip, wherein:
• the lower surface wall includes an upstream axial portion extending from the leading edge to a convex zone of said lower surface wall, a central portion extending from the convex zone to a concave zone of said lower surface wall, and a downstream axial portion extending from the concave zone to the trailing edge, the upstream axial portion and the downstream axial portion extending along an extension direction, and the central portion being tilted relative to the extension direction and having an inversion of curvature;
• the upper surface wall includes an upstream axial portion extending from the leading edge to a concave zone of said upper surface wall, a central portion extending from the concave zone to a convex zone of said upper surface wall, and a downstream axial portion extending from the convex zone to the trailing edge, the upstream axial portion and the downstream axial portion extending along the extension direction, and the central portion being tilted relative to the extension direction and having an inversion of curvature;
• said concave zones and said convex zones each extend over most of the height of the vane along its span axis;
• the concave zone of the lower surface wall faces the convex zone of the upper surface wall, and the concave zone of the upper surface wall faces the convex zone of the lower surface wall;
• each vane is a variable setting vane mounted to pivot about a radial axis coinciding with its leading edge;
• the upstream axial portion and the downstream axial portion of the lower surface wall extend constantly parallel to each other, and the upstream axial portion and the downstream axial portion of the upper surface wall extend constantly parallel to each other;
• two consecutive vanes delimit therebetween an inter-vane fluid passage channel being a baffle between central portions of the two consecutive vanes tilted at a tilt angle with respect to a longitudinal axis of the turbojet engine, the inter-vane fluid passage channel presenting a pitch which is a distance separating the two consecutive vanes in a top view along a circumference of the bladed wheel;
• and
• a relative pitch of the inter-vane fluid passage channel corresponding to a ratio of the pitch to a chord length of the central portion of the vanes is less than 0.6, and the tilt angle is less than 30°.