TURBOMACHINE VANE CASCADE Russian patent published in 2002 - IPC

FIELD: mechanical engineering; turbines. SUBSTANCE: proposed vane cascade has airfoil channels and vanes forming the channels. Profile sections of airfoil channels in meriodinal sections have curved middle line with front point directed to working medium flow and smoothly falling down from of curvature to chord connecting both ends of middle line at monotonic decrease of angle of declination between chord and tangential lines to middle line to zero value when moving front point to top of curvature. Middle line of profile sections is located at one side relative to chord and is mated with the latter in rear point of profile at acute angle of declination whose value monotonically increases on section from rear point to top of curvature and then smoothly decreases. Profile of vane is made symmetrical relative to middle line. Working medium flow in middle area of outlet section of airfoil channel is equalized in velocity to make it decreased towards zero value at least of two partial derivatives δV/δy, δ²V/δy² where V is flow velocity, y is step direction along indicated section of vane cascade. Medium flow in middle area of airfoil channel outlet section can be equalized in velocity so that values of two partial derivatives in central point of this area become simultaneously equal to zero δV/δy = 0, δ²V/δy² = 0. EFFECT: reduced step gradient of main flow behind vane rims, improved stability of vane flow and increased efficiency of turbomachine. 8 cl, 5 dwg