Guide vane airfoil for the hot gas flow path of a turbomachine
A guide vane airfoil for placement in a flow path portion of a turbomachine is provided, which, relative to a flow pattern in flow path portion, has a leading edge and, downstream thereof, a trailing edge, as well as a suction side and a pressure side; relative to a longitudinal axis of the turbomachine, viewed in the axial direction, in a radially inner portion, forming a first angle α with a circular arc about the longitudinal axis, and, in a radially outer portion, a second angle γ with a circular arc about the longitudinal axis. The guide vane airfoil is inclined in the outer portion, thus γ−90°, in terms of absolute value, being >0° (|γ−90°|>0°), and the guide vane airfoil being more highly inclined in the outer portion than in the inner portion, thus γ−90°, in terms of absolute value, being >α−90° (|γ−90°|>α−90°).
1. A guide vane airfoil for placement in a flow path portion of a turbomachine, the guide vane airfoil, relative to a flow pattern in the flow path portion, comprising:
a leading edge;
a trailing edge downstream of the leading edge;
a suction side and a pressure side;
a visible edge on the suction side of the guide vane airfoil, relative to a longitudinal axis of the turbomachine, viewed in the axial direction,
in a radially inner portion, forming a first angle α with a circular arc about the longitudinal axis, and,
in a radially outer portion, a second angle γ with a further circular arc about the longitudinal axis,
and
the guide vane airfoil being inclined in the outer portion, thus γ−90°, in terms of absolute value, being greater than 0° (|γ−90°|>0°), and
the guide vane airfoil being more highly inclined in the outer portion than in the inner portion, thus γ−90°, in terms of absolute value,
being greater than α−90° (|γ−90°|>α−90°);
wherein the visible edge in the radially inner and outer portion extends rectilinearly and, within a middle portion located between and adjoining the radially inner portion and the radially outer portion, merges transitionally from the first angle α into the second angle γ with a monotonic curvature profile, the middle portion having a middle portion radial extent that constitutes at least 5% and at most 25% of a radial height of the flow path portion, so that the inner portion with the radially inner portion rectilinearly-extending visible edge has an inner portion radial extent and the radially outer portion with the radially outer portion rectilinearly-extending visible edge together constitute at least 75% and at most 95% of the radial height of the flow path portion.
2. The guide vane airfoil as recited in claim 1 wherein the first angle α in the inner portion is at least 85° and at most 95°.
3. The guide vane airfoil as recited in claim 2 wherein
the first angle α in the inner portion is 90°.
4. The guide vane airfoil as recited in claim 1 wherein
the outer portion is inclined toward the suction side so that the second angle γ in the outer portion is greater than 90°.
5. The guide vane airfoil as recited in claim 4 wherein
the second angle γ in the outer portion is at least 95° and at most 120°.
6. The guide vane airfoil as recited in claim 1 wherein
the outer portion is inclined toward the pressure side so that the second angle γ in the outer portion is less than 90°.
7. The guide vane airfoil as recited in claim 6 wherein
the second angle γ in the outer portion is at least 85° and less than 90°.
8. The guide vane airfoil as recited in claim 1 wherein
the inner portion with the radially inner portion rectilinearly-extending visible edge has an inner portion radial extent that constitutes at least 20% and at most 50% of the radial height of the flow path portion.
9. The guide vane airfoil as recited in claim 1 wherein
the radially outer portion with the radially outer portion rectilinearly-extending visible edge has an outer portion radial extent that constitutes at least 25% and at most 55% of the radial height of the flow path portion.
10. The guide vane airfoil as recited in claim 8 wherein
the monotonic curvature profile is a strictly monotonic curvature profile.
11. A guide vane segment comprising guide vane airfoils,
each guide vane airfoil of the guide vane airfoils being as recited in claim 1 .
12. A module comprising:
a guide vane ring having at least one guide vane segment as recited in claim 11 , and, disposed upstream of the guide vane ring,
a rotor blade ring having rotor blade airfoils; any inclination of the rotor blade airfoils being less than that of the guide vane airfoil in the radially outer portion.
13. A jet engine comprising the module as recited in
claim 12 .
14. A method for designing the module as recited in
claim 12 comprising considering a wake of the upstream disposed rotor blade ring and, as a function thereof, adapting the inclination of the guide vane airfoil in the radially outer portion.
15. The guide vane airfoil as recited in claim 8 wherein
the inner portion with the radially inner portion rectilinearly-extending visible edge has an inner portion radial extent that constitutes at least 20% and at most 50% of the radial height of the flow path portion and the radially outer portion with the radially outer portion rectilinearly-extending visible edge has an outer portion radial extent that constitutes at least 25% and at most 55% of the radial height of the flow path portion.
16. The guide vane airfoil as recited in claim 8 wherein
the inner portion with the radially inner portion rectilinearly-extending visible edge has an inner portion radial extent that constitutes 40% of the radial height of the flow path portion and the radially outer portion with the radially outer portion rectilinearly-extending visible edge has an outer portion radial extent that constitutes 45% of the radial height of the flow path portion.