Turbine engine with a blade
A blade for a turbine engine with a wall separating a cooling fluid flow and a hot gas fluid flow and having a heated surface along which the hot gas fluid flow flows and a cooled surface facing the cooling fluid flow. A plurality of cooling holes each having a passage extending between an inlet at the cooled surface and an outlet at the heated surface. The outlet extending between an upstream end and a downstream end with respect to the hot gas fluid flow to define a distance, the passage defining a centerline forming a first angle (θ) with the heated surface.
1. A component for a turbine engine which generates a hot gas fluid flow, and provides a cooling fluid flow, comprising:
a wall separating the hot gas fluid flow from the cooling fluid flow and having a heated surface along which the hot gas fluid flow flows and a cooled surface facing the cooling fluid flow; and
at least one cooling hole comprising a passage extending between an inlet at the cooled surface and an outlet at the heated surface, the passage defining a centerline forming a first angle (θ) with the heated surface, the passage having a top wall and a bottom wall each extending from the inlet toward the outlet, and a layback surface defining at least a portion of the outlet, extending from the bottom wall to the heated surface, the layback surface forming a second angle (β) with the bottom wall and a third angle (Δ) with the heated surface;
wherein for any range of angle values (α):
(
α
low
≤
α
≤
α
hi
)
:
If
αhi
+
α
low
≤
θ
,
then
α
low
≤
Δ
≤
α
hi
;
and
If
αhi
+
α
low
≥
θ
,
then
α
low
≤
β
≤
α
hi
.
wherein the sum of the low and high angle values is equal to a switch value (θ s ):
α
hi
+
α
low
=
θ
s
.
2. The component of claim 1 , wherein the range of angle values is 5°≤α≤40°.
3. The component of claim 1 , wherein a low second angle (β low ) is greater than a low third angle (Δ low ):
β
low
>
Δ
low
.
4. The component of claim 1 , wherein a high second angle (β hi ) is greater than a high third angle (Δ hi ):
β
h
i
>
Δ
h
i
.
5. The component of claim 1 , wherein as the first angle (θ) increases to the switch value (θ s ), one of the second angle (β) or the third angle (Δ) increases at a first rate while the other of the second angle (β) or the third angle (Δ) remains constant within a range.
6. The component of claim 5 , wherein as the first angle (θ) increases above the switch value (θ s ), the other of the second angle (β) and the third angle (Δ) increases at the first rate while the other of the second angle (β) and the third angle (Δ) remains constant within a range.
7. The component of claim 1 , wherein the layback surface intersects the heated surface at a downstream end of the outlet, the top wall intersects the heated surface at an upstream end of the outlet and a straight-line distance measured from the downstream end to the upstream end defines a first dimension of the outlet.
8. The component of claim 7 , wherein the at least one cooling hole includes multiple cooling holes with each cooling hole having first dimensions within 5% of each other cooling hole.
9. The component of claim 8 , wherein the layback surface intersects the bottom wall at a junction and a length (L β ) measured along the first angle (θ) from the junction to the straight-line distance increases when the second angle (β) increases.
10. The component of claim 9 , wherein the passage further defines a hydraulic diameter (D h ) and for any constant distance (d const ), first, second, and third angles satisfy the following expression:
d
const
=
D
h
sin
θ
+
L
β
·
sin
β
sin
Δ
.
11. The component of claim 1 , wherein the second angle (β) and the third angle (Δ) have an interdependent relationship.
12. The component of claim 1 located within a turbine engine, comprising:
an engine core extending along an engine centerline and including a compressor section, a combustor, and a turbine section in axial flow arrangement and defining a flow path;
a temperature sensor within the engine core and configured to detect an exhaust gas temperature (EGT) within the engine core;
a set of nozzles circumferentially arranged in the turbine section and defining a number of nozzles (NN); and
a set of blades circumferentially arranged in the turbine section adjacent to, and downstream of, the set of nozzles, the set of blades defining a number of blades (NB);
wherein a blade in the set of blades comprises:
an outer wall bounding an interior and having an exterior surface, with the outer wall defining a pressure side and a suction side and extending between a leading edge and a trailing edge to define a chord-wise direction, and also extending between a tip and a root to define a span-wise direction;
a cooling conduit within the interior;
a tip radius (TR) defined between the engine centerline and the tip under standard day conditions of 15° C. at mean sea level altitude and 101.3 kPa atmospheric pressure;
a radial length (R) defined by a span-wise line extending between a first location on the outer wall and a second location on the outer wall, with the first location and the second location having a common chord-wise position;
a surface length (L max ) defined by a contour line along the outer wall between the first location and the second location at the common chord-wise position; and
a blade parameter (BP) defined as a ratio of the surface length to the radial length (BP=L max /R wherein the exhaust gas temperature EGT, the number of blades NB, the number of nozzles NN, the tip radius TR, and the blade parameter BP define a blade tip durability factor (BTDF) by the following expression:
BTDF
=
(
TR
EGT
)
×
(
NB
NN
)
×
BP
;
wherein the blade tip durability factor BTDF is between 0.020 and 0.033 in/° C., and the blade parameter BP is between 1-1.234.
13. A blade for a turbine engine which generates a hot gas fluid flow, and provides a cooling fluid flow, comprising:
a wall separating the hot gas fluid flow from the cooling fluid flow and having a heated surface along which the hot gas fluid flow flows and a cooled surface facing the cooling fluid flow; and
a plurality of cooling holes each comprising a passage extending between an inlet at the cooled surface and an outlet at the heated surface, the outlet extending between an upstream end and a downstream end with respect to the hot gas fluid flow to define a straight-line distance, the passage defining a centerline forming a first angle (θ) with the heated surface, a top wall, and a bottom wall each extending from the inlet toward the outlet, and a layback surface defining at least a portion of the outlet, extending from the bottom wall to the heated surface, the layback surface forming a second angle (β) with the bottom wall and a third angle (Δ) with the heated surface, wherein for any range of angle values (α):
(
α
low
<
α
<
α
hi
)
:
for at least a first cooling hole of the plurality of cooling holes α hi +α low <θ, and α low <Δ<α hi ; and
for at least a second cooling hole of the plurality of cooling holes α hi +α low >θ, and α low <β<α hi ;
wherein the distances for each of the plurality of cooling holes is maintained within 5% of each other as the first angle (θ) increases regardless of the location of the cooling hole on the blade, and
wherein the sum of the low and high angle values is equal to a switch value (θ s ), α hi +α low =θ s .
14. The blade of claim 13 , wherein the range of angle values is 5°<α<40°.
15. The blade of claim 13 , wherein the plurality of cooling holes are located along a region of the blade with high curvature.
16. The blade of claim 13 wherein for each of the plurality of cooling holes as the first angle (θ) increases to the switch value (θ s ) one of the second angle (β) and the third angle (Δ) increases at a first rate while the other of the second angle (β) and the third angle (Δ) remains constant within a range.
17. The blade of claim 16 wherein for each of the plurality of cooling holes as the first angle (θ) increases above the switch value (θ s ) the other of the second angle (β) and the third angle (Δ) increases at the first rate while the other of the second angle (β) and the third angle (Δ) remains constant within a range.
18. The blade of claim 12 wherein the layback surface intersects the bottom wall at a junction and a length (L β ) measured along the first angle (θ) from the junction to the straight-line distance increases when the second angle (β) increases.
19. The blade of claim 18 wherein the passage further defines a hydraulic diameter (D h ) and for any constant distance (d const ), first, second, and third angles satisfy the following expression:
d
const
=
D
h
sin
θ
+
L
β
·
sin
β
sin
Δ
.
20. The component of claim 13 , wherein a low second angle (β low ) is greater than a low third angle (Δ low ): β low >Δ low or wherein a high second angle (β hi ) is greater than a high third angle (Δ hi )
β
h
i
>
Δ
h
i
.