Aerodynamically mistuned airfoils for unsteady loss reduction
Aerodynamically mistuned airfoils for unsteady loss reductions are disclosed herein. An example apparatus disclosed herein includes a disk, a first airfoil coupled to the disk, the first airfoil having a first geometry, and a second airfoil coupled to the disk adjacent to the first airfoil, the second airfoil having a second geometry different than the first geometry, the first airfoil and the second airfoil produce non-uniform wake passing times during operation of the disk.
1. An apparatus comprising:
a disk;
a first airfoil coupled to the disk, the first airfoil having a first geometry including a first curvature with a corresponding first axial pressure distribution; and
a second airfoil coupled to the disk adjacent to the first airfoil, the second airfoil having a second geometry including a second curvature with a corresponding second axial pressure distribution, the first axial pressure distribution different than the second axial pressure distribution, the second airfoil having a same root-to-tip span length as the first airfoil;
a first channel between the first airfoil and the second airfoil; and
a second channel adjacent to the first channel, the first airfoil and the second airfoil producing non-uniform wake characteristics in the first channel and the second channel during operation of the disk,
wherein the disk is a rotor disk of a gas turbine engine,
wherein the first geometry includes a first thickness-to-chord ratio and the second geometry includes a second thickness-to-chord ratio, the first thickness-to-chord ratio different than the second thickness-to-chord ratio, and
wherein (1) the first thickness-to-chord ratio is less than the second thickness-to-chord ratio and (2) the second axial pressure distribution is more aft loaded than the first axial pressure distribution.
2. The apparatus of claim 1 , further including a third airfoil coupled to the disk adjacent to the second airfoil, the third airfoil having the first geometry.
3. The apparatus of claim 2 , wherein:
the second airfoil is spaced a first distance from the first airfoil; and
the third airfoil is spaced a second distance from the second airfoil, the first distance different than the second distance.
4. The apparatus of claim 1 , wherein the first geometry and the second geometry have a same maximum thickness.
5. The apparatus of claim 1 , wherein:
the first geometry has a first chord length; and
the second geometry has a second chord length, the first chord length different than the second chord length.
6. The apparatus of claim 1 , wherein the first curvature causes the first airfoil to have a first non-zero pressure loading, the second curvature causes the second airfoil to have a second non-zero pressure loading, the first non-zero pressure loading different than the second non-zero pressure loading.
7. A section of a gas turbine engine comprising:
a first row of airfoils; and
a second row of airfoils including:
a first airfoil having a first geometry including a first curvature with a corresponding first axial pressure distribution;
a second airfoil disposed adjacent to the first airfoil, the second airfoil having a second geometry including a second curvature with a corresponding second axial pressure distribution, the first axial pressure distribution different than the second axial pressure distribution, the second airfoil having a same root-to-tip span length as the first airfoil;
a first channel to receive first wake characteristics from the first row; and
a second channel to receive second wake characteristics from the first row, the first wake characteristics different than the second wake characteristics,
wherein the first row is a stator row and the second row is a rotor row,
wherein the first geometry includes a first thickness-to-chord ratio and the second geometry includes a second thickness-to-chord ratio, the first thickness-to-chord ratio different than the second thickness-to-chord ratio, and
wherein (1) the first thickness-to-chord ratio is less than the second thickness-to-chord ratio and (2) the second axial pressure distribution is more aft loaded than the first axial pressure distribution.
8. The section of claim 7 , wherein the second row further includes a third airfoil adjacent to the second airfoil, the third airfoil having the first geometry.
9. The section of claim 8 , wherein:
the second airfoil is spaced a first distance from the first airfoil; and
the third airfoil is spaced a second distance from the second airfoil, the first distance different than the second distance.
10. The section of claim 7 , wherein the first geometry and the second geometry have a same maximum thickness.
11. The section of claim 7 , wherein:
the first geometry has a first chord length; and
the second geometry has a second chord length, the first chord length different than the second chord length.
12. The section of claim 7 , wherein the first curvature causes the first airfoil to have a first non-zero pressure loading, the second curvature causes the second airfoil to have a second non-zero pressure loading, the first non-zero pressure loading different than the second non-zero pressure loading.