Rotor blade and guide vane airfoil for a gas turbine engine
View Patent ↗The invention refers to a rotor blade or guide vane airfoil for a gas turbine engine having a longitudinal axis and a source of cooling fluid. The airfoil has a pressure wall, a suction wall, a leading edge, a trailing edge and at least one cooling fluid flow passage. The cooling fluid flow passage is in fluid communication with the source of cooling fluid. Means for directing cooling fluid at least to the trailing edge are provided, whereas the cooling fluid flow passage including: a plurality of axially extending walls, each of the walls extending laterally between the pressure wall and suction wall. The plurality of walls are radially spaced within the cooling fluid flow passage such that adjacent pairs of walls define a channel. The axial spacing between the adjacent walls include in radial direction of the airfoil a pins and a ribs structure, wherein the pins holistic or approximately cover the axial height of the channel. The ribs have a deeper level with respect to the pins and the ribs establish a bridge-like connection between each of adjacent ribs.
1. A rotor blade or guide vane airfoil for a gas turbine engine having a longitudinal axis and a source of cooling fluid, the rotor blade or guide vane airfoil comprising:
a pressure wall;
a suction wall;
a leading edge;
a trailing edge;
at least one cooling fluid flow passage in fluid communication with the source of cooling fluid; and
means for directing cooling fluid at least to the trailing edge, wherein the at least one cooling fluid flow passage includes:
at least one axially extending wall, each axially extending wall extending laterally between the pressure wall and the suction wall, the at least one axially extending wall, pressure wall and suction wall being spaced within the at least one cooling fluid flow passage such that adjacent walls of the at least one axially extending wall, the pressure wall and the suction wall define a channel between the pressure wall and suction wall, a spacing between the adjacent walls of the at least one axially extending wall, the pressure wall and the suction wall including, in a flow direction of the cooling fluid, pins and ribs, wherein the pins are arranged along a length of the at least one cooling fluid flow passage and extend between the adjacent walls of the at least one axially extending wall, the pressure wall and the suction wall defining the channel, the ribs extend partially between the adjacent walls of the at least one axially extending wall, the pressure wall and the suction wall defining the channel, and the ribs establish a connection between adjacent pins, wherein a pitch of the pins with a larger cross-section in a span-wise direction is equal to or corresponds to a multiple of a pitch of the pins with a smaller cross-section and the pins with smaller cross-section are arranged downstream of the pins with the larger cross-section in the span-wise direction, wherein a dimension of each of the ribs is proportional to a dimension of the pins to which it is connected, a width of the ribs arranged between the pins with the larger cross-section being larger than a width of the ribs arranged between the pins with the smaller cross-section.
2. The rotor blade or guide vane airfoil according to claim 1 , wherein the ribs establish a connection between two adjacent pins.
3. The rotor blade or guide vane airfoil according to claim 1 , wherein the connection between each adjacent pin extends along at least one portion of a length of the channel in the flow direction of the cooling fluid.
4. The rotor blade or guide vane airfoil according to claim 3 , wherein the connection between each adjacent pin extends only along a first portion of length of the channel in the flow direction of the cooling fluid.
5. The rotor blade or guide vane airfoil according to claim 1 , wherein the ribs having a square or rectangular or trapezoidal cross-section.
6. The rotor blade or guide vane airfoil according to claim 5 , wherein a leading face of each rib with respect to the flow direction of the cooling fluid comprises an inclined or tapered surface.
7. The rotor blade or guide vane airfoil according to claim 5 , wherein the trapezoidal cross-section has a top width that is larger than 60% of a height of the ribs.
8. The rotor blade or guide vane airfoil according to claim 1 , wherein the ribs between two adjacent pins consists of at least one vortex generator having three triangular surfaces.
9. The rotor blade or guide vane airfoil according to claim 1 , wherein a pitch of the pins in a span-wise direction is decreased as a channel height and a pin cross section gets smaller.