JP3962931B2 - Method for forming cooling holes in gas turbine blades by image processing - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for forming a cooling hole in a gas turbine blade by image processing, and allows a large number of cooling holes to be created in a gas turbine blade in a short time on computer graphics so that it can be used for simulation of cooling design and the like. It is a thing.
[0002]
[Prior art]
Gas turbines, especially aero engines, are always required to be lightweight, fuel efficient and highly reliable. Therefore, the turbine inlet temperature is increased for the turbine, which is the main component of the engine, to cope with it. In addition, further improvement in cooling performance is required with the progress of materials.
[0003]
In order to improve the cooling performance of such a gas turbine, for example, as shown in FIG. 5, many cooling holes 2 are formed in the turbine blade 1 and film cooling by cooling air is performed.
[0004]
While the cooling performance of the cooling holes 2 formed in the turbine blade 1 varies depending on the arrangement and size thereof, the number of the cooling holes 2 is very large. In order to conduct experiments by forming cooling holes in an actual turbine blade by electric discharge machining, etc. Takes a lot of time and money.
[0005]
Therefore, simulation such as cooling design is performed by making cooling holes in the turbine blades using computer graphics.
[0006]
The conventional method for forming a cooling hole in a turbine blade by image processing is to first input and synthesize one CAD data of the cooling hole on the CAD data of the turbine blade alone, and then add one to the turbine blade alone. Open the cooling hole.
[0007]
Then, the CAD data of the turbine blade alone is in a state where the data for one cooling hole is increased.
[0008]
Next, CAD data of the next one cooling hole is inputted and synthesized on the CAD data of the turbine blade in a state where one cooling hole is formed, and a second cooling hole is made in the turbine blade alone. .
[0009]
Then, the CAD data of the turbine blade alone is in a state where data for two cooling holes is increased.
[0010]
In this way, all of the cooling holes are formed by repeatedly synthesizing the CAD data of a large number of cooling holes one by one into the CAD data of the turbine blade alone with the previous cooling holes formed. It was.
[0011]
[Problems to be solved by the invention]
However, since it is necessary to repeatedly input the CAD data of the cooling holes one by one to the CAD data of the turbine blade and to make the cooling holes, it takes a considerable time from the input of the CAD data of one cooling hole to the processing. There is a problem that it takes a long time of several days to form a large number of cooling holes.
[0012]
The present invention has been made in view of such problems of the prior art, and to a gas turbine blade by image processing that can efficiently form images of a large number of cooling holes on CAD data of a single turbine blade in a short time. An object of the present invention is to provide a method for forming a cooling hole.
[0013]
[Means for Solving the Problems]
In order to solve the above-described problems of the prior art, a cooling hole forming method for a gas turbine blade by image processing according to claim 1 of the present invention is based on CAD data for a single gas turbine blade based on predetermined three-dimensional coordinates. While storing, the cooling holes to be formed in the gas turbine blade alone are modeled, and individual CAD data to be formed in the gas turbine blade is input by using the modeled cooling holes, and these modeled cooling holes are input. After forming the CAD data of the cooling hole assembly in which all the cooling holes modeled from the individual CAD data of the holes are gathered, the CAD data of the gas turbine blade alone and the CAD data of the modeled cooling hole assembly are obtained. synthesized and then purified CAD data of the cooling hole assembly extra portion of the outer from the gas turbine blade single shape It is characterized in that as excluded.
[0014]
That is, according to the method of forming the cooling holes in the gas turbine blade by this image processing, a cooling hole model common to a large number of cooling holes formed in the gas turbine blade is used. The CAD data of the cooling hole assembly was created from the individual CAD data of all the cooling holes, and the CAD data of the cooling hole assembly was synthesized with the CAD data of the gas turbine blade and modeled. The CAD data of the cooling hole assembly of the extra portion outside the shape of the gas turbine blade corresponding to the difference between the cooling hole and the actual cooling hole is deleted, and the CAD data in the course of forming the cooling hole is deleted. A large number of cooling holes can be formed in a short time while minimizing the increase.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 and FIG. 2 are a flowchart and a process diagram according to an embodiment of a method for forming a cooling hole in a gas turbine blade by image processing according to the present invention.
[0016]
In this method of forming a cooling hole in a gas turbine blade by image processing, for image processing (computer graphics) by a computer, a reference for creating CAD data of the turbine blade 1 and the cooling hole 2 described in FIG. The following three-dimensional coordinates are determined.
[0017]
(1) Reference three-dimensional coordinate As this three-dimensional coordinate, for example, as shown in FIG. 3 (a), the positioning reference point on the platform is set as the origin O of the coordinate, and this origin O is passed through to the center line of the engine. Use the parallel direction as the X-axis, the radial reference line parallel to the stack line of the blade cross section, pass through the origin O and parallel to the radial reference line to the Z-axis, and further to these X-axis and Z-axis A perpendicular direction is defined for each Y axis. The positive directions of these X axis, Y axis, and Z axis are determined as follows.
[0018]
X axis: The direction from the front to the rear of the engine is the positive direction.
Y axis: The direction of the fingertip is positive in the left hand system perpendicular to the X and Z axes.
Z axis: The direction away from the engine center is the positive direction.
[0019]
(2) The CAD data of the turbine blade 1 alone is input to the computer and stored on the basis of the XYZ coordinates (see FIG. 1 (1)).
[0020]
(3) Next, the cooling holes are modeled (see FIG. 1 (2)).
[0021]
Modeling of the cooling holes, intended to be a common shape to all cooling holes Notwithstanding the arrangement of cooling holes 2 to be formed on the turbine blade 1, for example, as shown in FIG. 4, the cooling holes In the case of the cooling hole portion 4 with the diffuser 3 , the diffuser 3 is configured with three surfaces 3 a, 3 b, 3 c having a wide end and one surface 3 d without a wide end, and the cooling hole portion having a circular cross section is formed in the diffuser 3. Consider a model in which 4 are continuously formed.
[0022]
In this model of cooling holes, disposed in any position of the turbine blade can be located between the inner and outer walls, Yes so as not to interfere with the other inner wall and an outer wall, the outer portion and the cooling holes of the diffuser 3 The outer portion of the portion 4 has an extra portion when placed on the blade cross section of the turbine blade 1 (see FIG. 4D).
[0023]
Then, for example, when the cooling holes are formed in the diffuser 3 Tsukino cooling holes 4, each of length around the interface between the diffuser 3 and the cooling hole 4 is a 5 mm, the cooling holes 4 Is used as the size supported by the individual input data of the cooling holes, and the angle of the divergent portion is 10 degrees.
[0024]
(1) Angle that determines the direction required for inputting CAD data of cooling holes (see FIG. 3B) In FIG. 3B, the center line L of the cooling holes 2 on the turbine blade 1 is defined as XYZ. An angle formed by the line L1 formed by projecting the coordinates on the XY plane and the X axis is defined as an angle A. The angle A is 0 degree when the line L1 coincides with the positive direction of the X axis passing through the origin O, and the counterclockwise direction when the origin O is viewed from the positive direction of the Z axis is defined as 0 to 360 degrees. It varies in the range.
[0025]
Further, the coordinate obtained by rotating the XYZ coordinate around the Z axis by the angle A is defined as the X′-Y′-Z coordinate, and the center line L of the cooling hole 2 is projected onto the X′-Z plane. An angle formed between the line L2 and the Z axis is an angle B. This angle B is 0 degree when the line L2 coincides with the positive direction of the Z axis passing through the origin O, and the counterclockwise direction when viewed from the positive direction of the Y 'axis is the positive direction. Varies with a range of degrees.
[0026]
Furthermore, the angle is necessary only when the cooling hole 2 has a shape other than the round hole, and the coordinate obtained by rotating the X′-Y′-Z coordinate around the Y ′ axis by the angle B is X ″ -Y. The coordinates of “″ -Z ″ are determined, and an angle formed between the Y ″ axis and a vector defining the shape direction of the cooling hole on the X ″ -Y ″ plane is defined as an angle C.
[0027]
For example, in the case of a cooling hole having a cooling hole portion 4 with a diffuser 3 as shown in FIG. 4, the diffuser 3 is configured with three surfaces 3a, 3b, 3c having a divergent surface and one surface 3d having no divergent surface. However, an angle formed by a vector perpendicular to the surface 3d having no end spread and the Y ″ axis is an angle C. Note that the angle C also varies in the range of 0 to 360 degrees.
[0028]
In the case of the cooling hole portion 4 with the diffuser 3, it is necessary to indicate the size of the diffuser 3, and the depth D is used. This depth D is the ideal blade surface shape and the center of the cooling hole portion 4 . It is defined by the distance on the center line of the cooling hole portion 4 between the intersection of the line and the beginning of the diffuser 3 (the boundary surface between the diffuser and the cooling hole) (see FIG. 4D).
[0029]
(2) Input of CAD data of individual cooling holes (see FIG. 1 (3)).
[0030]
Since the coordinate system and the cooling hole model for representing the cooling holes are defined as described above, the following values are used as CAD data of the individual cooling holes.
[0031]
Coordinates (X, Y, Z) of blade outer surface for representing hole position, angles (A, B, C) representing hole direction, hole diameter, coordinates (X, Y, Z) of blade inner surface and diffuser depth By defining the length D, each cooling hole can be represented using computer graphics.
[0032]
Therefore, the above-mentioned CAD data is prepared for all the cooling holes to be formed in the turbine blade. For example, the CAD data of all the cooling holes is read from what is stored in the floppy disk or the like and input to the computer.
[0033]
(3) From the CAD data of all the cooling holes input to the computer in this way, the cooling hole assembly 5 is created as an image in a state where only all the cooling holes are modeled (FIGS. 1 (4) and 2 (2)). b)).
[0034]
When the cooling hole assembly 5 is created in this modeled state, the coordinates (X, Y, Z) of the blade outer surface of the cooling hole and the coordinates (X, Y) of the blade inner surface are selected from the CAD data of the individual cooling holes. (Y, Z) is used to determine the coordinates (X, Y, Z) of the intermediate point, and the center of the cooling hole 4 at the boundary surface between the diffuser 3 and the cooling hole 4 of the cooling hole modeled at this intermediate point And the size of the cooling hole 4 is determined based on the hole diameter data.
[0035]
(4) The image of the turbine blade 1 alone and the image of the cooling hole assembly 5 are synthesized (see FIG. 1 (5)).
[0036]
When the CAD data of the cooling hole assembly 5 and the CAD data of the turbine blade 1 stored in advance are combined on the same image, as shown in FIG. 2C, the cooling hole assembly 5 is formed on the turbine blade 1 alone. Are superimposed and displayed. The synthesis of such CAD data is based on the common three-dimensional coordinates (X, Y, Z) already described for both the CAD data of the turbine blade 1 alone and the CAD data of the cooling hole assembly 5. It can be easily synthesized.
[0037]
In the combined image of the turbine blade 1 and the cooling hole assembly, the modeled cooling holes are arranged at predetermined positions of the turbine blade, so that both ends of each cooling hole are separated from the blade outer surface and the blade inner surface. It is in a state of protruding outward.
[0038]
(5) Removal of the cooling hole outside the turbine blade (see FIG. 1 (6))
The coordinates (X, Y, Z) of the blade outer surface and the coordinates (X of the blade inner surface) which are inputted as individual CAD data of each cooling hole portion 4 on the synthesized image of the turbine blade 1 and the cooling hole assembly 5 , Y, Z) and data processing for removing both ends of the cooling hole portion 4 from the CAD data of the turbine blade in accordance with the shape of the outer surface and the inner surface of the blade.
[0039]
Then, an extra portion outside the turbine blade (inclusive of both the outside of the blade outer surface and the outside of the blade inner surface) at both ends of the modeled cooling hole is removed to form the shape of the cooling hole to be formed (FIG. 2). (See (d)).
[0040]
(6) In this way, an image of a turbine blade with cooling holes can be obtained (see FIG. 1 (7)).
[0041]
The turbine blade with cooling holes obtained in this way is as shown in FIG. 5, for example, and is used for simulation such as cooling design.
[0042]
As described above, according to the method of forming the cooling holes in the gas turbine blade by this image processing, a large number of cooling holes are modeled as one cooling hole, and the modeled cooling holes are converted into the turbine blades based on the position data. The CAD data of the cooling hole aggregate is synthesized separately from the CAD data, and the CAD data of the cooling hole aggregate can be created in a short time.
[0043]
Then, since the CAD data of the cooling hole aggregate and the CAD data of the turbine blade are synthesized, the synthesis in this case is compared with the case where the CAD data of the cooling holes is synthesized with the CAD data of the turbine blade one by one. Can be done in a short time. Furthermore, the turbine blade with the cooling hole can be easily obtained by deleting the extra portion from the CAD data of the cooling hole aggregate modeled as the turbine blade.
[0044]
【The invention's effect】
As described above in detail with the embodiment, according to the method for forming a cooling hole in a gas turbine blade by image processing according to the present invention, a cooling hole model common to a large number of cooling holes formed in the gas turbine blade. The CAD data of all the cooling holes that have been modeled is input, and the CAD data of the cooling hole assembly is created from the individual CAD data of all the cooling holes. The CAD data of the gas turbine blade is combined with the CAD data of the gas turbine blade, and the CAD data of the cooling hole aggregate in the excess portion outside the shape of the gas turbine blade corresponding to the difference between the modeled cooling hole and the actual cooling hole is deleted. Therefore, it is possible to obtain a turbine blade with cooling holes in which a large number of cooling holes are formed in a short time while minimizing the increase in CAD data during the formation of cooling holes. Can.
[0045]
In particular, even when the number of cooling holes reaches several hundred, the time for manufacturing turbine blades with cooling holes can be greatly reduced as compared with the conventional case where cooling holes are formed one by one.
[Brief description of the drawings]
FIG. 1 is a flowchart according to an embodiment of a method for forming a cooling hole in a gas turbine blade by image processing according to the present invention.
FIG. 2 is a process diagram according to an embodiment of a method for forming a cooling hole in a gas turbine blade by image processing according to the present invention.
FIG. 3 is an explanatory diagram of coordinates serving as a reference in an embodiment of a method for forming a cooling hole in a gas turbine blade by image processing according to the present invention.
FIG. 4 is a perspective view, a left side view, a front view, and a plan view of a cooling hole model in an embodiment of a method for forming a cooling hole in a gas turbine blade by image processing according to the present invention.
FIG. 5 is a perspective view according to an example of a gas turbine blade with a cooling hole to which the present invention is applied.
[Explanation of symbols]
1 Gas turbine blade (single unit)
Second cooling holes 3 the diffuser 4 cooling holes 5 cooling holes assembly

Claims (1)

While storing CAD data of a gas turbine blade alone based on predetermined three-dimensional coordinates, a cooling hole to be formed in the gas turbine blade alone is modeled, and the modeled cooling hole is formed in the gas turbine blade alone. Each CAD data to be input is input, and from the individual CAD data of the modeled cooling holes, the CAD data of the cooling hole assembly in which all the modeled cooling holes are gathered is formed. The CAD data and the CAD data of the modeled cooling hole assembly are synthesized, and then the CAD data of the cooling hole assembly of the extra portion outside the shape of the gas turbine blade alone is removed. A method for forming a cooling hole in a gas turbine blade by image processing.

Images