Device for creating and exploiting a pressure difference and the technical application thereof

Apparatus for extracting energy from a flowing fluid consisting of a split double cone perfused in an axial direction by a fluid medium, characterized in that the double cone is composed of two hollow cone trunks arranged axially with their smaller faces opposed to one another and having diameters d.sub.1 and d.sub.2 at a distance h and surrounded at the region of their smallest diameter by a coaxial cylindric tube with a connecting socket at its mantle surface at which a reduced pressure is produced wherein the aperture angles of the cones are between 1 and 10 degrees and fulfill the condition

• F=(1+ sin .theta..sub.1).sup.2 .multidot. sin.sup.2 .theta..sub.2 <0.02
• .theta..sub.1 representing the aperture angle of the entrance cone and .theta..sub.2 representing the aperture of the exit cone wherein the proportion of the smallest diameter d.sub.1 to the widest diameter d.sub.2 of the cones is between 1:1.5 and 1:200, and where d.sub.1 represents the smallest diameter of the entrance cone, the two cone trunks are split at a line downstream from the virtual section circle of the two cones by the distance h/2, the smaller end of the exit cone being cut by the length h, so that the free distance between the two cones is h, the smallest diameter of the exit cone truck is ##EQU3## where D.sub.2 represents the greatest diameter and L.sub.2 the length of the exit cone trunk and where h is between 0.001 and 20 d.sub.1 .