CN104411982B - There is the turbine guide blades improving blade profile - Google Patents

Abstract

The present invention relates to a set of turbine guide blades, described blade includes multiple blade arranged around a ring, each blade is respectively provided with leading edge and extends between root end and end, tip, leading edge at the root end of each blade is positioned at the upstream of the leading edge of vane tip end relative to airflow direction, and the skew of leading edge between these two ends is more than the 10% of blade height.The also tangential superposition with one group of guide blades towards suction face side of this principal character is combined, this group guide blades is characterised by, it is directed towards the curve that the suction face side of blade continues to increase by the tangential curve superposed formed along the position in the direction tangent with the ring of the center of gravity of continuous leaf cross-section along the height of blade, described curve ratio close to the tip ends of blade has the reinforcement gradient towards suction face side compared with the remainder of described curve, described curve close to the average gradient of the tip ends of blade more than at least 1.2 times of average gradient of the curve in part between 30% and 90% of blade height.

Description

There is the turbine guide blades improving blade profile

Technical field

The present invention relates to turbine straightener field, and relate to the turbine including this straightener.

Background technology

Fig. 1 shows the bypass turbine for aircraft propulsion.It fan 10 including carrying air stream, The core being referred to as main flow Fp of described air stream is injected in compressor 12, described compressor The turbine 14 of 12 supply one driving fans.

Time peripheral part of stream FS that is referred to as of air stream is passing the fixing blade being arranged on fan downstream Ring after, for being ejected in air to provide its part of part thrust of turbine 1.It is referred to as rectifying This ring of straight device 20 (also being known as " outlets direct blade " that acronym is OGV) makes The air stream leaving fan can be aligned, limit loss the most as far as possible.

It practice, straightener reduces by the loss (such as, the pressure loss) of 0.1% can cause assembly Efficiency increases by 0.2 point, and described assembly includes fan and straightener, corresponding with between efficiency in loss Naturally the aerodynamic loading of engine and associated fan is depended on.

According to the distance with turbine axis, the effectiveness of straightener depends especially on the air leaving fan The gradient of the specific physical quantity of stream.This is referred to as by the fan supply to straightener.These physical quantity examples Air velocity, its compression ratio or its temperature in this way.

The aligning of air stream is provided by the blade of straightener, and setting and geometry about it are suitable to this and supply Should.In the evolution in this field, the first straightener blade is bidimensional, has generally rectangular shape Shape.But, these geometries reduce incompatible with the loss improvement required by new design and size.Cause This, the three-dimensional straightener blade profile of exploitation, such as in file FR 2 828 709 like that.

And, the supply profile of new straightener causes pursuing the straightener along these lines and designs.

Especially, the blade that the straightener proposed in the file US 2005/008494 is had around The rotation axis of straightener radially extends, and have include along 27 degree radially and 33 degree it Between angle at the tip ends that tilts, this is to be produced to reduce the fan by being positioned at straightener upstream Noise.

But, the straightener proposed within this document does not make to improve the air in straightener stream The distribution of stream, does not the most reduce loss.

Summary of the invention

The present invention has the target proposing straightener, has about its blade and is adapted to correct at least one State the geometry of shortcoming.

On this point, the present invention has a kind of turbine straightener as its object, and it includes multiple The blade arranged around ring, described ring is placed in the middle on the axis of turbine, and each described blade has leading edge also Extending between root end and tip ends, the leading edge at the root end of each blade is relative to air-flow It is located at the upstream of leading edge at the tip ends of blade, along the orientation measurement of the axis of turbine, The skew of leading edge between these two ends is more than the 10% of the height of blade, and the feature of straightener exists In, along the tangential direction of ring of the center of gravity of continuous blade profile (along the height of blade), including position The tangential superimposed curves put is directed towards the ever-increasing curve of upper surface of blade, described curve close to The tip ends of blade has towards the upper surface (E) increased relative to the remainder of described curve Slope, close to the G-bar of curve of tip ends of blade more than the height being included in blade At least 1.2 times of the slope of a curve in part between 30% and 90%.

Advantageously, but selectively, the present invention also has at least one following characteristics:

-be included in blade close to the sweep of end, tip height 90% and 100% between.

The leading edge of-each blade is included at the tip ends of described blade relative to air-flow direction The downstream location of the position of leading edge at least some of.

Being partly comprised in of downstream part of-leading edge at the tip ends of blade is positioned at blade height In the region of the leading edge between 60% and 100%.

-with the position consistency of leading edge at the tip ends of blade and the point of leading edge that positions is positioned at leaf Between 60% and 80% of sheet height.

Leading edge at the root end of-each blade is located at the tip of blade relative to air-flow direction At one segment distance of the upstream of the leading edge of end, described distance is included in the 12% and 20% of blade height Between, described distance is along turbine axis orientation measurement.

The invention still further relates to a kind of turbine, described turbine includes at least one aligning according to the present invention Device.

Accompanying drawing explanation

From following description the most exemplary and nonrestrictive and that must be read with reference to the drawings, The other features, objects and advantages of the present invention will become clear from, wherein:

-Fig. 1 of having been described above schematically shows bypass type turbine.

-Fig. 2 a is the partial schematic diagram of straightener.

-Fig. 2 b shows the profile of the straightener blade including multiple blade profile.

-Fig. 3 a shows that the layout of the leading edge of the blade of the air-flow direction relative to turbine develops.

-Fig. 3 b shows the superimposed curves of the tangential direction relative to straightener.

-Fig. 4 a shows the distribution of the air velocity along the blade height at root of blade, one side Face, for the blade consistent with an embodiment of the present invention (solid-line curve), is on the other hand used for having two Dimension geometry (imaginary curve) another blade.

-Fig. 4 b shows the pressure of the air of the blade through the height along the blade at root of blade Loss, for one and another one of the two blade.

-Fig. 4 c shows the differentiation of the loss of air pressur through the blade along the whole height of blade, uses One and another one in the two blade.

-Fig. 5 a and 5b show respectively according to prior art and according to the present invention at the tip of blade Separation member.

Detailed description of the invention

With reference to Fig. 1, foregoing bypass turbine 1 has the straightener 20 of fan 10 and OGV type, To align the secondary air stream FS from fan.

With reference to Fig. 2 a, straightener 20 includes that multiple blade 22, described blade 22 are evenly distributed in whirlpool Ring 29 placed in the middle on the axis of turbine (not shown in figures) is around.Shown in Fig. 2 a and 2b Blade do not represent geometry of the present invention.

Each blade 22 all includes leading edge 23 and trailing edge 24, is being referred to as the radial inner end 25 of root of blade And it is referred to as between the radial outer end 26 of vane tip extending.Leading edge 23 and trailing edge 24 limit lower surface I and upper surface E.

Also using following symbol: X is turbine axis or the direction of engine axis, and Y is relative to straightener The tangential direction of ring 29, Z is that each blade is along its radially extending direction.

The reach of the leading edge at root of blade

With reference to Fig. 3 a, relative to the direction X of engine axis, at each point on blade, show leading edge Position.This curve is referred to as the layout of leading edge.

It addition, all distances height based on blade is all nondimensionalization: so, before vertical coordinate represents Edge is relative to the height and position of the total height of blade, and abscissa represents relative in vane tip end 26 The skew of the leading edge of the position E of the leading edge at place, described skew is shown as the percentage ratio of blade height.

As shown in the figure, along the direction X of engine axis, relative at vane tip end 26 The position E, the position A of the leading edge at the root end 25 of blade of leading edge upstream offset.This Skew is more than the 10% of blade height.It preferably, between 10% and 20% of blade height, preferably exists Between 12% and 20% of blade height, more preferably between 15% and 20%.

This movement forward of the root of blade makes the air stream in blade height to be better distributed.Right In the part extended between root end and the 50% of its height of blade, along the air-flow of blade height This distribution of value be shown in Fig. 4 a.

For the blade (solid-line curve corresponding in Fig. 4 a to 4c) proposed, can be relative to other leaves Sheet, blade the most of the prior art (imaginary curve) observes better performance.Particularly at blade At the 10% of height, proposed profile be can be observed and make flow velocity can increase above 6%.

Tangential superposition towards upper surface

See Fig. 2 b, folding of the continuous blade profile 27 that each blade 22 is typically included in blade height Add.

See Fig. 3 b, the tangential superimposed curves of display blade, by the center of gravity of blade profile 27 relative to The position composition of the direction Y that ring 29 is tangent.

This curve using blade height is also nondimensionalization, and initial point is the center of gravity of blade root portion Position A '.Additionally, abscissa on the occasion of corresponding to towards the skew of blade upper surface, negative value is the most right Ying Yu is towards the skew of blade lower surface.

As shown in figure 3b, tangential superimposed curves is towards the curve that the upper surface of blade constantly declines. Make the separation of the air stream at vane tip to reduce towards this tangential superposition of upper surface, make at blade Speed and flow velocity at root can increase, and make the pressure loss in the region to reduce.Particularly, Can be observed in fig. 4b, the loss at root of blade can subtract due to the blade profile that proposed Few close to 2%.

Advantageously, tangential with the blade towards upper surface of the reach of the leading edge of the blade at root of blade Superposition combines, to combine the effect obtained and to be reduced as far as the pressure loss.

And, return to Fig. 3 b, the tangential superimposed curves of blade at vane tip relative to The remainder of blade advantageously has the slope of increase.

Preferably, the part in this curve has the region between 90% and 100% of blade height C ' D ' so that the G-bar of this part G-bar of D ' (i.e. part C ') is high at blade Part B between 30% and 90% of degree ' at least 1.2 times of G-bar of C '.

Air-flow through the blade of the tangential superposition having towards lower surface is modeled, through having towards upper The air-flow of the blade of the tangential superposition on surface slope at vane tip increases.

Result is respectively displayed in Fig. 5 a and 5b, and each figure all shows blade 22 and at vane tip The separated region ZD of air-flow.It should be noted that for the first blade, in fig 5 a, this separated region The separated region of the ZD the second blade much larger than Fig. 5 b according with the present invention.

Being finally returned to Fig. 3 a, the layout of the leading edge of blade also has relative to the direction X of engine axis There is the part in the downstream of the position E being located at the leading edge at vane tip.

Accordingly, there exist the some C of the leading edge in line of the position E with the leading edge at vane tip.This Point is advantageously located between the 60% of blade height and 80%, so that being positioned at the part in the downstream of position E This is extended partially in the region between 60% and 100% of blade height.

Point C can be more preferably located between 65% and 75% of blade height.

Therefore, the respective position of A, C and E refers to the leading edge of the blade close to vane tip Layout has hook-like shape, has recessed opening relative to the upstream of engine axis.

So, close to this part of most advanced and sophisticated blade of blade than the remainder distance turbine of blade Fan is farther, and this makes to be limited in the acoustic perturbation at vane tip.

So, the geometry proposed makes to improve the performance of straightener blade, reduces at blade point The separation of the air-flow at end.

Claims (7)

1. a turbine straightener (20), it includes multiple around the axle being centered in described turbine The blade (22) that ring (29) on line is arranged, each described blade (22) is respectively provided with leading edge (23), And extend between root end (25) and tip ends (26),

Described leading edge (23) at root end (25) place of each described blade (22) is relative to air-flow Direction is located at the upstream of the described leading edge (23) at tip ends (26) place of described blade, along institute State the described leading edge (23) between these two ends of the orientation measurement of the axis (X) of turbine Skew is more than the 10% of the height of described blade (22),

It is characterized in that, by the height along described blade (22) along continuous blade profile (27) The tangential superimposed curves of the position composition of the tangential direction (Y) of the ring (29) of center of gravity is directed towards described leaf Upper surface (E) the ever-increasing curve of sheet (22),

Described curve is tip ends (26) place the remaining relative to described curve close to blade (22) Remaining part divides the slope with the increase towards described upper surface (E), and described curve is close to described leaf The G-bar at tip ends (26) place of sheet is more than between 30% and 90% of described blade height At least 1.2 times of the G-bar of the described curve in part,

The leading edge (23) of each described blade (22) includes the point being positioned at described blade relative to airflow direction Downstream at least some of of the position of the described leading edge (23) at end end (26) place.

Turbine straightener (20) the most according to claim 1, wherein close to described tip Between 90% and 100% of the height being partly comprised in described blade (22) on the slope of end (26).

Turbine straightener (20) the most according to claim 1, wherein said is partly comprised in In the region of the described leading edge (23) between 60% and 100% of the height being positioned at described blade (22).

4. according to the turbine straightener (20) described in claim 1 or 3, wherein with at described leaf The point position of the position of the described leading edge at tip ends (26) place of sheet described leading edge (23) in line Between 60% and 80% of described blade height.

5. according to the turbine straightener (20) in any of the one of claim 1-3, Qi Zhong The leading edge at root end (25) place of each described blade (22) is positioned at described relative to described airflow direction At one segment distance of the upstream of the described leading edge (23) at tip ends (26) place of blade, described distance Being included between 10% and 20% of described blade height, described distance is along the axis of described turbine (X) orientation measurement.

Turbine straightener (20) the most according to claim 5, wherein said distance is included in Between 12% and 20% of described blade height.

7. a turbine (1), it includes that at least one is according to any one institute in aforementioned claim The straightener (20) stated.