JP2002221006A - Throat area measurement method of turbine nozzle - Google Patents

Abstract

(57) [Summary] [Problem] To reduce the time required for measuring the change in the area of the throat area. SOLUTION: Nozzle blade data is taken into 3D CAD (step S1), the coordinate space is divided into ten in the height direction of the nozzle blade (step S2), and antinodes and trading edges of one nozzle blade are divided for each divided region. The projection curve is formed by projecting the boundary curve between the boundary curve and the rear surface of the other nozzle blade perpendicularly (step S7), and an outer passage and an inner passage that connect the upper end and the lower end of the boundary curve and the projection curve are created. (Step S8), a substantially trapezoidal area surrounded by the boundary curve, the projection curve, the outer passage, and the inner passage is obtained (Step S9), and the calculated areas are added to calculate a throat area area (Step S1).
0) A throat area area calculation method is used to calculate a ratio of a throat area area based on data of a nozzle blade whose angle has been changed at a predetermined throat adjustment angle by using a design state and a throat area area ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throat of a turbine nozzle used for measuring beforehand a change in a throat area area due to a change in an angle of a nozzle blade when designing a turbine nozzle of a gas turbine used as an aircraft gas turbine engine or the like. It relates to an area measurement method.

[0002]

2. Description of the Related Art In a gas turbine, a fuel is mixed with air compressed by a compressor and burned, and power is obtained by directly rotating a rotor of a high-pressure turbine at high speed by a high-temperature and high-pressure combustion air flow generated by the combustion. As shown in FIG. 3, an example of a portion of the high-pressure turbine is formed between a hub-side shroud 2 located on an inner peripheral side and a tip-side shroud 3 located on an outer peripheral side thereof. A nozzle vane 4 as a variable vane forming a turbine nozzle, a turbine shaft 5
The rotor blades 6 are arranged in the direction of the turbine shaft 5 so as to be integrally rotated in the circumferential direction, and the nozzle blades 4 are provided in a stacking manner provided for each nozzle blade 4 by the operation of the operating mechanism 7. The direction (angle) can be changed synchronously within a predetermined throat adjustment angle range around the axis (rotation axis) 8, and the angle of each nozzle blade 4 is adjusted according to the load. By changing the area of the throat area formed between the adjacent nozzle blades 4 and adjusting the flow rate of the combustion air introduced into the moving blade 6 through the turbine nozzle, matching with the compressor on the upstream side is achieved. In the case of a type in which a low-pressure turbine is present on the downstream side, matching with the low-pressure turbine can be achieved.

Therefore, when designing the turbine nozzle, when the angle of the nozzle blade 4 is swung within a predetermined throat adjustment angle range, how much the combustion air flow rate increases or decreases, that is, two nozzles It is necessary to measure in advance how much the throat area area, which is the area of the most narrowed portion of the gas flow path between the wings 4, changes.

For this purpose, conventionally, as shown in a flow chart of FIG.
As shown in FIG. 5, the model is arranged in a three-dimensional coordinate space as a model as shown in FIG. 5 (step S1), and the three-dimensional coordinate space is divided into a plurality of segments at required intervals corresponding to the height of each nozzle blade 4. In the area d, for example, 10 divisions (step S2)
After that, as shown in FIG. 6, for each of the divided regions d, the back of one nozzle blade 4 (outside in the bending direction of the blade cross section) facing each other and the antinode of the other nozzle blade 4 (the cross section of the blade cross section) The operator sets the location 9 (the inner side in the bending direction) which is closest (step S3), and obtains the cross-sectional shape of each divided region at the set location 9 two-dimensionally (step S4). The throat is configured to calculate the area of the two-dimensionally projected shape (step S5) and to calculate the area of the throat area by adding the values calculated for the respective divided regions (step S6). Using the area area calculation method, first, the throat area area is calculated by performing the above-described throat area area calculation method based on the data of the two nozzle blades 4 in the angular arrangement in the design state, In addition, on 3DCAD, the two nozzle blades 4 are moved around a stacking shaft 8 mounted on each of the nozzle blades 4 within a preset throat adjustment angle, for example, by adjusting the angle range. 10
A model of the nozzle blade 4 is sequentially created for each equally divided swing angle, and for each created blade model, the throat area area is calculated using the throat area calculation method shown in FIG. A calculation operation is performed, and a throat area area ratio is calculated based on the calculated throat area area for each swing angle, where the throat area area when the nozzle blades 4 are arranged at an angle in the designed state is 100%. The value of the throat area area ratio is plotted on the XY coordinate with the horizontal axis (X axis) as the swing angle of the nozzle blade 4 as shown in FIG. The correlation of the change in the area of the throat area can be measured at the design stage.

[0005]

However, in the above-described conventional method for measuring the throat area of a turbine nozzle, the position of the narrowest point 9 between two nozzle blades 4 arranged in a three-dimensional coordinate space is determined by an operator. Was manually set, so that the sectional shape of the divided area at the above-mentioned location was different for each worker, and therefore, there was a problem that the obtained throat area area had individual differences, and two nozzles were required. Wing 4
When creating a wing model whose angle is changed in synchronization with
On the DCAD, the operator manually changes the angle of each wing one by one, and determines whether or not the angle has been changed on the 3DCAD screen. 3D before and after changing the angle of the wing model
Since the difference on the CAD screen is very small, there is also a problem that a postponement operation due to an error such as not changing the angle of one of the wings or erroneously changing the angle in the opposite direction induces the work efficiency.

Accordingly, the present invention reduces the time required for the work of creating a wing model and reduces the design data of the nozzle wings so that there is no difference in the throat area area calculated due to operator mistakes or individual differences. The purpose of the present invention is to provide a method for measuring a throat area of a turbine nozzle, which can standardize a series of procedures for setting a throat area based on a wing model formed from and calculating a throat area area, thereby enabling automation. is there.

[0007]

According to the present invention, in order to solve the above-mentioned problems, first, data of two adjacent nozzle blades are fetched into 3D CAD to obtain three-dimensional coordinate data based on turbine nozzle design data. After being arranged in the space, the height direction of the two nozzle blades is divided into a plurality of regions, and then, for each of the divided regions, the boundary curve between the antinode of one nozzle blade and the trading edge is defined as the other. A projection curve is created by projecting vertically on the back side of the nozzle blade, and an outer passage and an inner passage that pass through the upper and lower ends of the boundary curve and the projection curve are created.
Calculate the area of a substantially trapezoid enclosed by the boundary curve, the projection curve, the outer passage, and the inner passage, and calculate the throat area area between the two nozzle blades by adding the area calculated for each divided region. In addition, by calculating the throat area area in the case of changing the angle of each of the above-mentioned nozzle blades by a required angle in the same phase around the predetermined stacking axis provided respectively, the angle of the nozzle blades is similarly calculated. A throat area measurement method for a turbine nozzle that measures a change in the throat area area due to the change.

After the design data of the nozzle blade is taken into 3D CAD and divided into a plurality of regions in the height direction of the nozzle blade, the boundary curve between the antinode of one nozzle blade and the trading edge and the boundary curve are converted to the other. A throat area is defined as a region surrounded by a projection curve formed by vertically projecting the back surface of the nozzle blade, and an outer passage and an inner passage connecting the upper end and the lower end of the boundary curve and the projection curve. Therefore, the throat area is uniquely derived from the data of the nozzle blades, and thereby the throat area area is uniquely calculated. or,
If the swing angle is set when the angle of the nozzle blade is changed, the throat area area in a state where the angle is changed for each swing angle is also uniquely calculated as described above,
The procedure for calculating the throat area is standardized. Therefore, by programming and automating each work procedure,
The time required for the operation can be greatly reduced as compared with the conventional case.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an embodiment of a method for setting a throat area of a turbine nozzle according to the present invention.
As shown in the flow of the throat area area calculation method in FIG. 1, similarly to steps S1 and S2 in FIG. 4, first, in the same manner as that shown in FIG. The nozzle wings 4 as a model are arranged in the three-dimensional coordinate space by taking it up (step S1), and the height direction of the arranged nozzle wings 4 is divided into a plurality of, for example, ten regions (step S1). S
2) After that, as shown in FIG. 2, in each divided region, an antinode (inward in the direction of curvature of the wing cross-sectional shape) and a trading edge (trailing edge) created in the process of designing a wing model in one nozzle blade 4. Is perpendicularly projected on the back surface (outer surface in the curved direction of the blade cross section) of the other nozzle blade 4 to form a projection curve 11 (step S7),
Next, the outer side (chip side) connecting the upper ends of the boundary curve 10 and the projection curve 11 along the upper end of each divided region.
A passage 12 and an inner (hub-side) passage 13 connecting the lower ends of the boundary curve 10 and the projection curve 11 along the lower end of each divided area are created (step S8).
Next, after obtaining the area of the substantially trapezoid formed by being surrounded by the boundary curve 10, the projection curve 11, the outer passage 12, and the inner passage 13 (step S9), the area of the substantially trapezoid calculated for each divided region is obtained. Is added to calculate the throat area area (step S10).

Now, when the change in the throat area due to the change in the angle of the nozzle blades 4 is to be obtained, the data of the two adjacent nozzle blades 4 is fetched on 3D CAD, and then the surface between the two blades and the stacking shaft 8 , The swing angle range of the nozzle blade 4 is input, and the number of angle divisions for equally dividing the angle range is, for example, 10
Then, the number of blades in the entire circumferential direction of the turbine nozzle is input.

Next, using the method for calculating the throat area area shown in FIG. 1, the throat area area is first calculated based on the data of the two nozzle blades 4 in the angular arrangement in the design state, as in the prior art. Then, on the 3D CAD, the two nozzle blades 4 are separated by a swing angle obtained by equally dividing the angle range set as described above into 10 around the stacking shaft 8 provided on each of the nozzle blades 4. A model of the nozzle blades 4 is sequentially created, and for each created blade model, a throat area area is calculated using the throat area area calculation method shown in FIG. From the throat area area, the throat area area ratio with the throat area area being 100% when the nozzle blades 4 are arranged at an angle in the designed state is calculated. The value of the calculated issued throat area ratio of, by conventional displaying the diagram plotted on a such XY coordinate shown similarly in FIG. 7, and displays the correlation between the swing angle of the nozzle vanes 4.

As described above, in each divided region, the boundary curve 10 between the antinode of one nozzle blade 4 and the T / E, and the projection curve obtained by projecting the boundary curve 10 perpendicularly to the back surface of the adjacent nozzle blade. The throat area area is obtained by adding the area of a substantially trapezoid surrounded by an outer passage 12 and an inner passage 13 connecting the upper end and the lower end of the boundary curve 10 and the projection curve 11 to each other. Since it is possible to calculate the throat area area when the design data of the nozzle blade 4 is given, the throat area area can be uniquely derived and the processing can be automated. It is possible to eliminate the possibility that the throat surface can be made with stable quality, and to set the range of the throat adjustment angle to 10 or the like. For the blade model created for each of the divided swing angles, a throat surface of stable quality can be created in the same manner as described above, and the throat area area can be calculated. In the nozzle design stage, the change in the throat area area when the angle of the nozzle blade is changed within the throat adjustment angle can be easily obtained, so that the increase or decrease in the air flow rate passing through the turbine nozzle can be easily obtained. Therefore, matching with the front and rear of the high pressure turbine can be easily achieved.

It should be noted that the present invention is not limited to only the above-described embodiment. When determining the swing angle of the nozzle blade 4, the throat adjustment angle may be set arbitrarily.
It is needless to say that the angle may be divided into other than equal parts, and that various changes may be made without departing from the scope of the present invention.

[0015]

As described above, according to the method for setting a throat area of a turbine nozzle of the present invention, first, data of two adjacent nozzle blades are fetched into 3D CAD based on design data of the turbine nozzle. After being arranged in the three-dimensional coordinate space, the height direction of the two nozzle blades is divided into a plurality of regions. Then, for each of the divided regions, a boundary curve between the antinode and the trading edge of one nozzle blade is formed. Is projected perpendicularly to the back side of the other nozzle blade to create a projection curve, and an outer passage and an inner passage that pass through the upper and lower ends of the boundary curve and the projection curve are created. By calculating the area of a substantially trapezoid surrounded by the projection curve, the outer passage, and the inner passage, and adding the area calculated for each divided region, The throat area area between the two nozzle blades is calculated, and further, the throat area area when the two nozzle blades are changed in angle by a required angle in the same phase with respect to a predetermined stacking axis provided respectively. Is calculated in the same manner, so that the change in the throat area area due to the change in the angle of the nozzle blades is measured. Therefore, each procedure for calculating the throat area area from the data of the nozzle blades captured on 3D CAD is described. Standardization is possible, and since each of these work procedures can be programmed and automated, the time required for the work can be greatly reduced as compared with the conventional one, and the work efficiency can be improved. Since the work procedure is standardized, mistakes can be prevented, and there are individual differences in the shape of the set throat area. Jill fear is not,
Since it is possible to set the throat area with stable quality, it is possible to easily obtain the change in the throat area area when the angle of the nozzle blade is changed within the throat adjustment angle in the turbine nozzle design stage, It is possible to easily obtain an increase or decrease in the flow rate of the air passing through the nozzle, and it is possible to easily achieve matching between the front and rear of the high-pressure turbine.

[Brief description of the drawings]

FIG. 1 is a diagram showing a flow of a throat area area calculation method in an embodiment of a turbine nozzle throat area measurement method of the present invention.

FIG. 2 is a schematic diagram showing a state in which projection curves, outer and inner passages are created in one divided area in steps S3 to S5 in the flow of FIG.

FIG. 3 is a schematic cut-away side view showing an example of a portion of a high-pressure turbine.

FIG. 4 is a diagram showing a flow of a throat area area calculation method used conventionally.

FIG. 5 is a flow chart of a process in step S1 of FIG.
It is the schematic which shows the state which arrange | positioned the data of the nozzle blade taken in on 3DCAD in the three-dimensional coordinate space.

FIG. 6 is a flowchart showing a process in step S3 of FIG.
It is a figure showing the state where the portion where the nozzle blades approached most was set.

FIG. 7 is a diagram showing the correlation of a change in the throat area area ratio with a change in the angle of the nozzle blade.

[Explanation of symbols]

 d Division area 4 Nozzle blade 10 Boundary curve 11 Projection curve 12 Outer passage 13 Inner passage

Claims (1)

[Claims] 1. Based on design data of a turbine nozzle, first, data of two adjacent nozzle blades is taken into 3D CAD and arranged in a three-dimensional coordinate space, and then the height directions of the two nozzle blades are determined. Divided into a plurality of regions, and then, for each of the divided regions, create a projection curve by projecting the boundary curve between the antinode of one nozzle blade and the trading edge perpendicular to the back surface of the other nozzle blade While creating an outer passage and an inner passage that pass through the upper end and the lower end of the boundary curve and the projection curve,
Calculate the area of a substantially trapezoid enclosed by the boundary curve, the projection curve, the outer passage, and the inner passage, and calculate the throat area area between the two nozzle blades by adding the area calculated for each divided region. In addition, by calculating the throat area area in the case of changing the angle of each of the above-mentioned nozzle blades by a required angle in the same phase around the predetermined stacking axis provided respectively, the angle of the nozzle blades is similarly calculated. A method for measuring a throat area of a turbine nozzle, wherein a change in a throat area area due to the change is measured.