CN110779726B - Fluid pressure distortion simulation device - Google Patents
Fluid pressure distortion simulation device Download PDFInfo
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- CN110779726B CN110779726B CN201810852023.3A CN201810852023A CN110779726B CN 110779726 B CN110779726 B CN 110779726B CN 201810852023 A CN201810852023 A CN 201810852023A CN 110779726 B CN110779726 B CN 110779726B
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- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M15/00—Testing of engines
- G01M15/02—Details or accessories of testing apparatus
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Abstract
The invention aims to provide a fluid pressure distortion simulation device which comprises a distortion simulation net and a plurality of plugging columns, wherein the distortion simulation net comprises a honeycomb base net and ring-shaped parts, the honeycomb base net is a honeycomb grid formed by splicing regular hexagonal geometric unit bodies with the same size, and at least part of meshes of the honeycomb base net are plugged by the plugging columns. The pressure distortion simulation device has the characteristics of universality and quick adjustment.
Description
Technical Field
The invention relates to a fluid pressure distortion simulation device.
Background
In actual operation of an aircraft engine, pressure distortion can be generated at an engine inlet due to the influence of working conditions such as crosswind and maneuvering flight. Both theory and practice show that pressure distortion at the engine inlet can have a negative effect on engine performance and stability. In order to simplify the test device and reduce the test conditions in the engine test, a simulation method is often adopted to establish a pressure distortion map consistent with the real conditions of the engine. The pressure distortion simulation device is a test device for generating a specific pressure distortion map of the aerodynamic section of the engine, and can be seen in fig. 1.
The simulation net or the simulation board is the most common pressure distortion simulation device at present, and has the characteristics of simple manufacture, convenient installation and high precision.
For example, chinese invention patent CN103234756A discloses a net type distortion device for a large bypass ratio engine, which specifically discloses: the sticking net is a group of semicircular nets with different specifications and is used for generating intake distortion, and the sticking net with corresponding structural parameters is selected according to the requirement of a distortion index; the base net is a 360-degree whole net and is used for supporting the pasting net and used as a supporting framework of the pasting net to ensure the structural strength of the pasting net; the framework is of eight support plates adopting standard airfoil-shaped design profiles and an outer ring welding structure, is used for supporting a base net and pasting the net, and meets the pneumatic design requirement.
However, this type of design has two major disadvantages:
one is to make multiple sets of distortion simulation meshes (plates). The distortion simulation device and the pressure distortion map are in one-to-one correspondence, namely, one set of simulation net (plate) can only simulate one specific pressure distortion map under specific flight conditions and engine working conditions. In actual engine tests, because the flight conditions and working conditions of the engine to be simulated are more, the corresponding pressure distortion maps are also more, the distortion simulation nets (plates) to be manufactured are also more (generally, the number of the distortion simulation nets (plates) is from several to dozens), and the applicability of the distortion simulation nets (plates) is poor.
And secondly, the adjustment complexity of the distortion simulation network is high and the period is long. After the distortion simulation net (plate) is designed and finished according to the target pressure distortion map by a certain method, an air blowing test is needed, and the distortion simulation net (plate) is adjusted by comparing the test distortion map with the target pressure distortion map. The distortion simulation net is generally a metal wire for adjusting different blocking degrees, the distortion simulation plate is generally used for adjusting the blocking degree by opening holes at a proper position, and the adjustment is generally carried out by 2-3 rounds, so that the adjustment is complex and the period is long.
Disclosure of Invention
The object of the invention is a fluid pressure distortion simulation device which is versatile and fast adjustable. Compared with the traditional distortion simulation net (plate), the device has the characteristics of universality and quick adjustment, can simulate any pressure distortion map by using a set of simulation device, and can greatly reduce the number of sets of pressure distortion simulation net (plate) required by the test; meanwhile, the distortion map is adjusted by adopting the modularized plugging column, so that the adjustment period of the distortion simulation device can be shortened, and the test efficiency can be improved.
The invention provides a fluid pressure distortion simulation device which comprises a distortion simulation net and a plurality of plugging columns, wherein the distortion simulation net comprises a honeycomb base net and ring-shaped parts, the honeycomb base net is a honeycomb grid formed by splicing regular hexagonal geometric unit bodies with the same size, and at least part of meshes of the honeycomb base net are plugged by the plugging columns.
In one embodiment, a single said plugging column is in a triple configuration plugging three mesh openings or in a double configuration plugging two mesh openings.
In one embodiment, the plugging column comprises a top portion and a column portion, the boundary size of the top portion is larger than the boundary size of the mesh holes plugged by the plugging column, and the boundary size of the column portion is smaller than the boundary size of the mesh holes plugged by the plugging column.
In one embodiment, a bottom hole perpendicular to the cylindrical surface is provided on a side of a portion of the cylindrical portion away from the top portion.
In one embodiment, the height of the bottom hole from the top is greater than the height of the honeycomb base web and is less than or equal to the sum of the height of the honeycomb base web and the radius of the bottom hole.
In one embodiment, the bottom hole of the plugging column is tangent to a lower edge of the honeycomb based mesh.
In one embodiment, the top portion is formed by a plurality of regular hexagonal cells corresponding to a union number, and the width of each regular hexagonal cell is greater than the width of each regular hexagonal geometric cell body of the honeycomb base net.
In one embodiment, the thin-walled structure extends downward at an edge line that is set back inward from an outer edge of the top by a predetermined distance, and the column portion is broken to include a plurality of columns at a position where a plurality of regular hexagonal cells defining the edge line intersect.
In one embodiment, the annular member is fixedly connected to the outer periphery of the honeycomb base net, the annular member comprises an upper flange disc and a lower flange disc, and the fluid pressure distortion simulation device is connected with the test piece through the flange discs.
In one embodiment, the diameter of the honeycomb base web is equal to the diameter of the inlet channel of the test piece.
In one embodiment, the width of the regular hexagonal geometric unit cell is 1/30 the diameter of the honeycomb base web.
The invention also provides a simulation method for generating fluid pressure distortion, which comprises the following steps: arranging a honeycomb base net, wherein the honeycomb base net is a honeycomb grid formed by splicing regular hexagonal geometric unit bodies with the same size; arranging a plurality of plugging columns; and plugging corresponding meshes of the honeycomb base network by using the plugging columns according to the target pressure distortion map.
The invention adopts polygons for cell separation to form a honeycomb base network, and each polygon forms local pressure distortion in a blocking mode. The airflow is blocked by adding a blocking column on the honeycomb base net; when the airflow flows through the distortion simulation device, the corresponding area of the blocking column forms a low-pressure area. According to the shape of the target pressure distortion map, the required target pressure distortion map can be generated by installing the plugging column at the corresponding position, so that the pressure distortion simulation device has the function of adjusting both the pressure distortion index and the map.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:
fig. 1A and 1B are schematic views of a pressure distortion simulation panel and its corresponding pressure map, wherein fig. 1A is the pressure distortion simulation panel and fig. 1B is the pressure map corresponding to fig. 1A.
Fig. 2A and 2B are schematic diagrams of a target pressure distortion map and a simulation method thereof, wherein fig. 2A is the target pressure distortion map, and fig. 2B is a schematic diagram of a simulation method according to the present invention corresponding to fig. 2A, in which a black area represents an area to be occluded.
Fig. 3A and 3B are structural diagrams of a distortion simulation net according to an embodiment of the present invention, in which fig. 3A is a perspective view of the distortion simulation net and fig. 3B is a top view of the distortion simulation net.
Figure 4 is a schematic diagram of a single regular hexagonal geometric unit cell of a cellular base mesh comprising a distortion simulation mesh in accordance with an embodiment of the present invention.
Figure 5 is a cross-sectional view of a distortion simulation mesh in accordance with an embodiment of the present invention.
Fig. 6 is a block diagram of a triple plugging column according to an embodiment of the present invention.
Fig. 7 is a block diagram of a twin plugging column according to an embodiment of the present invention.
Fig. 8 is a bottom view of a triple occlusion column according to an embodiment of the invention.
Fig. 9 is a front view of a triple plugging column according to an embodiment of the present invention.
Fig. 10A and 10B are front effect views of the installation of a plugging column into a distortion simulation net according to an embodiment of the present invention, fig. 10A is a whole effect view, and fig. 10B is a partially enlarged view of an installation site, wherein the plugging column has two forms of a triple plugging column and a double plugging column.
Fig. 11A and 11B are back side effect views corresponding to fig. 10, fig. 11A is a whole effect view, and fig. 11B is a partially enlarged view of a mounting portion.
Fig. 12A and 12B are bottom views corresponding to fig. 11, in which fig. 12A is a view of the overall effect, and fig. 12B is a view of a mounting portion partially enlarged.
Detailed Description
Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
Fig. 1 is a schematic diagram of a pressure distortion simulation board and a corresponding pressure map in the prior art, wherein corresponding holes are formed in the pressure distortion simulation board according to a target pressure distortion map, so as to simulate target pressure distortion. In the design, a plurality of sets of different pressure distortion simulation plates need to be manufactured in order to correspond to different pressure maps, so that the adjustment is time-consuming and labor-consuming.
The invention is further described with reference to the following figures and detailed description.
The invention adopts polygons to perform cell separation to form a honeycomb grid type honeycomb base network, and each polygon forms local pressure distortion in a blocking mode. The airflow blockage is caused by inserting blockage columns into corresponding meshes of the honeycomb base network; when the airflow flows through the fluid pressure distortion simulation device, the corresponding area of the blocking column forms a low-pressure area. According to the pressure distortion map to be generated, the required target pressure distortion map can be generated by installing the plugging column at the corresponding position, so that the fluid pressure distortion simulation device has the function of adjusting both the pressure distortion index and the map.
Fig. 2A and 2B schematically illustrate the basic principle of the present invention. For example, for the target pressure pattern shown in fig. 2A, a plugging column with an appropriate plugging degree may be added at a position corresponding to the low pressure region to form a cell plugging state as shown in fig. 2B, thereby forming a target pressure distortion pattern corresponding to the pressure gradient of fig. 2A, wherein the black area in fig. 2B represents a cell with a plugging column installed in the honeycomb-based mesh, and the white area represents a cell without a plugging column installed.
The fluid pressure distortion simulation apparatus 1 includes a distortion simulation net 11 and a plurality of clogging cylinders 12. The plugging columns 12 are installed into corresponding mesh holes of the distortion simulation net 11 so as to generate the desired target pressure distortion, and a specific cooperation effect of the two will be described in detail later with reference to fig. 10A.
Fig. 3A and 3B show the structure of the distortion simulation net 11. With further reference to fig. 5, the distortion simulation net 11 includes a ring member a and a honeycomb base net B. The honeycomb base net B is a honeycomb grid spliced by adopting regular hexagonal geometric unit bodies B1 with the same size, and each regular hexagonal geometric unit body B1 is provided with a regular hexagonal mesh. It was mentioned above that the clogging plugs 12 are fitted to the corresponding meshes of the distortion simulation net 11, i.e., the clogging plugs 12 are inserted into the meshes of the honeycomb base net B.
The ring-shaped member A is fixedly connected with the outer periphery of the honeycomb base net B. In fig. 3, the annular member a includes upper and lower flange disks, and the fluid pressure distortion simulation apparatus 1 is connected to the test piece through the flange disks. As shown in fig. 3, the flange disk may be provided with a plurality of screw holes so that the flange disk may be screwed to the test piece. In general, in the blowing test, the diameter d of the honeycomb base net B (also the diameter of the annular inner wall of the annular member a as indicated in fig. 3B) is equal to the diameter of the inlet duct of the test piece, so as to completely cover the inlet duct. The diameter of the honeycomb base net B can be smaller than that of the air inlet channel of the test piece and does not completely cover the air inlet channel, or can be larger than that of the air inlet channel of the test piece and exceeds the cross section of the air inlet channel. The ring member a may not be circular as long as it can perform the function of fitting the distortion simulation net 11 to the test piece.
The hexagonal geometry cells B1 that make up the cellular network B are sufficiently large to allow finer control of pressure distortion. However, if the number of the regular hexagonal geometric unit cells B1 constituting the honeycomb base net B is too large, the walls of the regular hexagonal geometric unit cells B1 may have too much influence on the flow field. Preferably, the width of the regular hexagonal geometric unit cell B1 is 1/30 of the diameter d of the honeycomb base net B, as shown in fig. 4.
Fig. 6 and 7 show two types of plugging columns 12, a triple plugging column C and a double plugging column D. The plugging columns 12 are designed to be in a multi-connected mode, and the installation and fixation of the plugging columns are considered, so that the plugging columns are prevented from being blown into the main flow by air flow.
Generally, the plugging column 12 includes a top portion F and a column portion G. The boundary size of the column portion G is smaller than that of the mesh hole clogged by the clogging cylinder 12 so that the column portion G can be inserted into the mesh hole. And the boundary size of the top part F is larger than that of the net holes blocked by the blocking pillars 12, so that the blocking pillars 12 can be stuck on the honeycomb base net B and the air flow is prevented from flowing through.
In the present embodiment, the top F is formed of a plurality of regular hexagonal cells corresponding to the number of connections. Specifically, as shown in fig. 8, the top F of the triple plugging column C is formed by splicing three regular hexagonal units, and the top F of the double plugging column D is formed by splicing two regular hexagonal units. The width t of a single regular hexagonal cell of the plurality of regular hexagonal cells constituting the top F is slightly larger than the width (d/30 in the present embodiment) of the single regular hexagonal geometric cell body B1 of the honeycomb base net B.
As shown in fig. 8, the column portion G of the clogging cylinder 12 is a thin-walled structure extending downward from an edge line inwardly retracted from the outer edge of the top F by a predetermined distance, the edge line being an outer contour line when a plurality of regular hexagonal cells smaller than the plurality of regular hexagonal cells constituting the top F are put together, the column portion being broken at a position where the plurality of regular hexagonal cells defining the edge line intersect, and thus the column portion G of the clogging cylinder 12 is constituted by a plurality of separate thin-walled structures. Specifically, as shown in fig. 6 to 8, the column G of the triple occlusion column C is composed of three columns G1 having four edges, and the column G of the double occlusion column D is composed of two columns G1 having five edges.
As shown in fig. 8, the distance between the opposite sides (i.e., parallel sides) of the above-mentioned single column constituting the column portion G of the clogging column 12 is defined as the width b of the column portion G of the clogging column 12. To better complete the assembly, the width B of the column portion G of the plugging column 12 is slightly smaller than the width (d/30 in the present embodiment) of the single regular hexagonal geometric unit cell B1 of the honeycomb grid B after considering the machining error, so that the column portion G is inserted into the mesh of the corresponding regular hexagonal geometric unit cell B1.
As shown in fig. 9, the column part G of the plugging column 12 is provided with a bottom hole E perpendicular to the column surface, specifically, the bottom hole E is provided on the side of the part of the column part G away from the top F for connecting the adjacent plugging column 12 to fix it with the distortion simulation mesh 11. In order to connect and fix the plugging column 12, the height k of the bottom hole E from the top F of the plugging column 12 is greater than the height of the honeycomb base net B, and is less than or equal to the sum of the height of the honeycomb base net B and the radius r of the bottom hole E, and the specific numerical value can be determined according to the processing precision of a device object. The structural size of the duplex plugging column D is the same as that of the triple plugging column C. Preferably, when the plugging column 12 is mounted to the distortion simulation net 11, that is, when the top F of the plugging column 12 is contacted to the honeycomb base net B, the position of the bottom hole E of the plugging column 12 is tangential to the lower edge of the honeycomb base net B, and the tangential includes being close to tangential, and the closer to tangential, the more favorable the fixation of the plugging column 12 and the distortion simulation net 11.
For a given target pressure distortion map, for example, referring to fig. 2, a given aerodynamic cross-section pressure distortion map may be made identical to the target pressure map by installing and adjusting the corresponding position of the triple plugging column C or the double plugging column D.
Fig. 10, 11 and 12 are a front effect view, a back effect view and a bottom view of the plugging column 12 installed in the distortion simulation net 11 according to the embodiment of the present invention, respectively, and the effect of installing and matching the plugging column 12 with the distortion simulation net 11 can be clearly seen. It should be noted that, in the practical use of the pressure distortion simulation device, the number and combination form of the triple plugging columns and the double plugging columns should be reasonably selected according to the simulated distortion map.
The invention also provides a simulation method for generating fluid pressure distortion, which comprises the following steps: arranging a honeycomb base network, wherein the honeycomb base network is formed by splicing regular hexagonal geometric unit bodies with the same size; arranging a plurality of plugging columns; and according to the target pressure distortion map, plugging corresponding meshes of the honeycomb base network by using the plugging columns.
The foregoing embodiments are primarily intended to simulate pressure distortion of an air stream passing through an inlet, but may also be applied to other pressure distortion of a fluid, such as a liquid passing through a port.
The above embodiments provide a universal, fast-adjustable honeycomb fluid pressure distortion simulation apparatus to reduce the number of conventional gas turbine intake distortion simulation nets (plates), reduce the manufacturing cost, reduce the manufacturing period, improve the applicability of the simulation apparatus, and improve the test efficiency.
The above description is only an embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can understand that the modifications or substitutions within the technical scope of the present invention are included in the scope of the present invention, and therefore, the scope of the present invention should be subject to the protection scope of the claims.
Claims (10)
1. A fluid pressure distortion simulation device is characterized by comprising a distortion simulation net and a plurality of plugging columns, wherein the distortion simulation net comprises a honeycomb base net and ring-shaped parts, the honeycomb base net is a honeycomb grid formed by splicing regular hexagonal geometric unit bodies with the same size, and at least part of meshes of the honeycomb base net are plugged by the plugging columns;
the plugging column comprises a top part and a column part, the boundary size of the top part is larger than that of the meshes plugged by the plugging column, the boundary size of the column part is smaller than that of the meshes plugged by the plugging column, and bottom holes perpendicular to the column surface are arranged on the side surface of the part, far away from the top part, of the column part.
2. A fluid pressure distortion simulation apparatus as set forth in claim 1 wherein a single said plugging column is in a triple pattern plugging three mesh openings or a double pattern plugging two mesh openings.
3. The fluid pressure distortion simulation apparatus of claim 1, wherein the height of the bottom cells from the top is greater than the height of the honeycomb base web and is equal to or less than the sum of the height of the honeycomb base web and the radius of the bottom cells.
4. A fluid pressure distortion simulation apparatus as set forth in claim 1, wherein the bottom hole of the plugging column is tangent to a lower edge of the honeycomb base net.
5. A fluid pressure distortion simulation device as set forth in claim 1, wherein the top portion is formed of a plurality of regular hexagonal cells corresponding to a union number, and the width of a single regular hexagonal cell is larger than the width of a single regular hexagonal geometric cell body of the honeycomb base net.
6. The fluid pressure distortion simulation apparatus of claim 1, wherein the column portion is a thin-walled structure extending downward at an edge line that is set back inward from an outer edge of the top by a predetermined distance, and the column portion is broken to include a plurality of columns at positions where a plurality of regular hexagonal cells defining the edge line intersect.
7. A fluid pressure distortion simulation apparatus as claimed in claim 1, wherein the annular member is fixed to the outer periphery of the honeycomb base net, the annular member comprises upper and lower flange discs, and the fluid pressure distortion simulation apparatus is connected to the test piece through the flange discs.
8. A fluid pressure distortion simulation apparatus as set forth in claim 1, wherein the honeycomb base net has a diameter equal to that of the inlet port of the test piece.
9. A fluid pressure distortion simulation device as set forth in claim 1, wherein the width of the regular hexagonal geometric unit cell is 1/30 times the diameter of the honeycomb base web.
10. A simulation method for generating a fluid pressure distortion, comprising:
arranging a honeycomb base net, wherein the honeycomb base net is a honeycomb grid formed by splicing regular hexagonal geometric unit bodies with the same size;
arranging a plurality of plugging columns; and is
And according to the target pressure distortion map, utilizing the plugging columns to plug corresponding meshes of the honeycomb base network.
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| CN201810852023.3A CN110779726B (en) | 2018-07-30 | 2018-07-30 | Fluid pressure distortion simulation device |
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| CN201810852023.3A CN110779726B (en) | 2018-07-30 | 2018-07-30 | Fluid pressure distortion simulation device |
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| CN110779726B true CN110779726B (en) | 2021-06-11 |
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| CN113567141B (en) * | 2020-04-28 | 2024-02-02 | 中国航发商用航空发动机有限责任公司 | Distortion generating device, simulation method thereof and pressure distortion characteristic test system |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US3759091A (en) * | 1971-07-02 | 1973-09-18 | Gen Electric | Engine inlet distortion testing apparatus |
| CN202351046U (en) * | 2011-11-23 | 2012-07-25 | 中航商用航空发动机有限责任公司 | Modularized engine air inlet distorted mesh device |
| CN103835984B (en) * | 2014-03-06 | 2016-04-13 | 南京航空航天大学 | Detachable flow-disturbing bar type high-order rotational distortion generator |
| WO2017192976A1 (en) * | 2016-05-06 | 2017-11-09 | Frohnapfel Dustin J | Improved generalized flow profile production |
| CN106404407B (en) * | 2016-10-20 | 2018-08-14 | 北京动力机械研究所 | Adjustable fanning strip flow distortion simulator |
| CN107843435A (en) * | 2017-11-24 | 2018-03-27 | 北京动力机械研究所 | Engine variable sector inlet pressure distortion analog board |
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