CN111175007A - Blade surface flow visualization method based on HSV mode - Google Patents
Blade surface flow visualization method based on HSV mode Download PDFInfo
- Publication number
- CN111175007A CN111175007A CN201911410329.4A CN201911410329A CN111175007A CN 111175007 A CN111175007 A CN 111175007A CN 201911410329 A CN201911410329 A CN 201911410329A CN 111175007 A CN111175007 A CN 111175007A
- Authority
- CN
- China
- Prior art keywords
- blade
- photos
- mode
- flow
- hsv
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M9/00—Aerodynamic testing; Arrangements in or on wind tunnels
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M9/00—Aerodynamic testing; Arrangements in or on wind tunnels
- G01M9/06—Measuring arrangements specially adapted for aerodynamic testing
- G01M9/065—Measuring arrangements specially adapted for aerodynamic testing dealing with flow
- G01M9/067—Measuring arrangements specially adapted for aerodynamic testing dealing with flow visualisation
Landscapes
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Indicating Or Recording The Presence, Absence, Or Direction Of Movement (AREA)
Abstract
The invention belongs to the technical field of wind power generation experiments, and particularly relates to a blade surface flow visualization method based on an HSV mode, which comprises the following steps: step 1, uniformly sticking red silk threads on the suction surface of a leaf; step 2, shooting the running blades in a multi-angle mode by using a camera; step 3, detecting the color of the photo by adopting an HSV mode to realize automatic identification of the silk thread; and 4, screening qualified photos for statistical analysis, and realizing visualization of the flow field on the surface of the blade. The invention can observe the swinging angle of the silk thread on the surface of the blade very intuitively, and reflects the flowing condition of the surface of the blade. By adopting the HSV mode, probability distribution statistics can be carried out according to the swing angle of the silk thread on the surface of the blade, a flow separation interval is given, and a cloud chart is printed for display, so that an experiment of visualization of an external field flow field of the wind power plant is realized.
Description
Technical Field
The invention belongs to the technical field of wind power generation experiments, and particularly relates to a blade surface flow visualization method based on an HSV mode.
Background
Wind energy is a clean renewable resource, and therefore, wind power generation technology has been rapidly developed in China in recent years. Wind tunnel experiments are used as a main technical means for researching wind turbines, and are approved consistently by research accuracy. In wind tunnel experiments, the advantages and the importance of flow field visualization are increasingly highlighted.
The oil film method and the silk thread method are two reliable flow display technologies, wherein the oil film method adopts grease with certain viscosity to be uniformly coated on the surface of a test model. When the blowing experiment is carried out, under the friction of air, the distribution of the oil film is changed to a certain extent, and a trace similar to a wall-near friction line is displayed. However, the oil film method has the following limitations: the oil film method is mainly used for wind tunnel experiments of small plane blade grids; because the wind turbine blades are long, the linear speed of the rotation of the blades is greatly different. The centrifugal force of the oil films at different wind wheel radii is also greatly different. Therefore, the viscosity and thickness of the oil film are not easily controlled. In addition, because the blades are long, the oil film coating operation time is long, so that the viscosity of the oil films at different blade extension positions is changed, and experimental errors are caused. In addition, the oil film method can only measure the condition that the wind speed is fixed at one time. Therefore, the oil film method is not suitable for the field experiment. The wire tracer method is a blade surface flow display technology which can be used in an external field experiment at present. The silk thread method is to stick a certain number of silk threads on the surface of the blade according to a certain arrangement mode. The wires are deflected in a certain direction by the action of the fluid near the surface of the blade. After a certain time of blowing, the position of the silk thread is relatively fixed, and the direction of the silk thread shows the local speed direction of the flow.
Currently, the topological structure of the flow on the blade surface can be obtained by photographing and other image processing methods. The wire method is not influenced by the geometrical length of the blade, the change of wind speed and other factors. However, the conventional silk thread experimental scheme does not grasp the technology of visualizing the flow field through the silk thread, the information of the flow field on the surface of the blade cannot be accurately and visually displayed through the silk thread, the silk thread swings within a certain angle range in consideration of the unsteady effect of actual flow, the probability average is required to be carried out on the silk thread angle, the angle of the local silk thread averagely deviating from the main flow direction is obtained, and whether transition or separation occurs in the local flow is judged through a certain transition or separation standard.
Disclosure of Invention
Aiming at the problems, the invention provides a blade surface flow visualization method based on an HSV mode, which comprises the following steps:
step 1, uniformly sticking red silk threads on the suction surface of a leaf;
step 2, shooting the running blades in a multi-angle mode by using a camera;
step 3, detecting the color of the photo by adopting an HSV mode to realize automatic identification of the silk thread;
and 4, screening qualified photos for statistical analysis, and realizing visualization of the flow field on the surface of the blade.
The red thread had a diameter of 0.4cm and a length of 4 cm.
The camera adopts an industrial camera, is arranged on the ground 50 meters away from the unit, and aims at the blade suction surface.
The step 3 further comprises: automatically inquiring the record of the operation condition according to the photo creation time, and automatically filing the photo according to the wind speed interval; and carrying out automatic rotation operation on the photos, and rotating the photos to a uniform angle.
The step 4 further comprises: extracting red pixels, realizing automatic identification of silk threads, screening photos according to the identification rate, and removing unqualified photos; and carrying out statistical analysis according to the screened qualified photos, and giving a flow separation interval according to probability distribution, wherein the flow separation interval is displayed by a cloud picture.
The invention has the beneficial effects that:
the red silk thread is pasted on the surface of the blade, and the swinging angle of the silk thread on the surface of the blade can be observed very intuitively through a picture obtained by an industrial camera, so that the flowing condition of the surface of the blade is reflected.
By adopting the HSV mode, probability distribution statistics can be carried out according to the swing angle of the silk thread on the surface of the blade, a flow separation interval is given, and a cloud chart is printed for display, so that an experiment of visualization of an external field flow field of the wind power plant is realized.
Drawings
FIG. 1 is a flow chart of a blade surface flow visualization method based on HSV mode.
FIG. 2 is a schematic view of a wire being attached to a surface of a wind turbine blade.
Fig. 3 is a diagram of the effect after recognition.
Fig. 4 is a cloud image effect diagram finally presented.
Detailed Description
The preferred embodiments will be described in detail below with reference to the accompanying drawings.
The invention provides a blade surface flow visualization method based on an HSV mode, which comprises the following steps:
step 1, uniformly sticking red silk threads on the suction surface of a leaf;
step 2, shooting the running blades in a multi-angle mode by using a camera;
step 3, detecting the color of the photo by adopting an HSV mode to realize automatic identification of the silk thread;
and 4, screening qualified photos for statistical analysis, and realizing visualization of the flow field on the surface of the blade.
The red thread had a diameter of 0.4cm and a length of 4 cm.
The camera adopts an industrial camera, is arranged on the ground 50 meters away from the unit, and aims at the blade suction surface.
The step 3 further comprises: automatically inquiring the record of the operation condition according to the photo creation time, and automatically filing the photo according to the wind speed interval; and carrying out automatic rotation operation on the photos, and rotating the photos to a uniform angle.
The step 4 further comprises: extracting red pixels, realizing automatic identification of silk threads, screening photos according to the identification rate, and removing unqualified photos; and carrying out statistical analysis according to the screened qualified photos, and giving a flow separation interval according to probability distribution, wherein the flow separation interval is displayed by a cloud picture.
FIG. 1 is a flow chart of the experimental method. FIG. 2 is a schematic diagram of silk threads pasted on the surface of a wind turbine blade, after the silk threads are pasted according to certain arrangement, a camera is arranged on the ground at a position about 50m away from a tower, the camera is aligned with a suction surface of the wind turbine blade, and a picture is taken under the condition that a fan operates.
And (3) processing the shot picture by using a programmed HSV mode-based program to identify the silk thread, wherein the identification condition is shown in figure 3.
And automatically identifying the photos in batches, screening the photos according to the identification rate, setting an option of the maximum number of silk threads, and when the identification number of the silk threads of the photos is less than 90% of the maximum number of the silk threads, determining that the photos are unqualified, removing the photos and not participating in probability statistics. And rejecting unqualified photos. And (4) performing statistical analysis according to the screened qualified photos, giving a flow separation interval according to probability distribution, and displaying the flow separation interval by using a cloud chart, wherein the effect is shown in an attached figure 4.
The embodiments are only preferred embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (5)
1. An HSV mode-based blade surface flow visualization method is characterized by comprising the following steps:
step 1, uniformly sticking red silk threads on the suction surface of a leaf;
step 2, shooting the running blades in a multi-angle mode by using a camera;
step 3, detecting the color of the photo by adopting an HSV mode to realize automatic identification of the silk thread;
and 4, screening qualified photos for statistical analysis, and realizing visualization of the flow field on the surface of the blade.
2. The HSV mode-based blade surface flow visualization method of claim 1, wherein the red filament is 0.4cm in diameter and 4cm in length.
3. The blade surface flow visualization method based on HSV mode according to claim 1, wherein said camera is an industrial camera, and is arranged on the ground 50m away from the unit, and the lens is aligned with the suction surface of the blade.
4. The HSV mode-based blade surface flow visualization method of claim 1, wherein said step 3 further comprises: automatically inquiring the record of the operation condition according to the photo creation time, and automatically filing the photo according to the wind speed interval; and carrying out automatic rotation operation on the photos, and rotating the photos to a uniform angle.
5. The HSV mode-based blade surface flow visualization method of claim 1, wherein said step 4 further comprises: extracting red pixels, realizing automatic identification of silk threads, screening photos according to the identification rate, and removing unqualified photos; and carrying out statistical analysis according to the screened qualified photos, and giving a flow separation interval according to probability distribution, wherein the flow separation interval is displayed by a cloud picture.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911410329.4A CN111175007A (en) | 2019-12-31 | 2019-12-31 | Blade surface flow visualization method based on HSV mode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911410329.4A CN111175007A (en) | 2019-12-31 | 2019-12-31 | Blade surface flow visualization method based on HSV mode |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111175007A true CN111175007A (en) | 2020-05-19 |
Family
ID=70655945
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911410329.4A Pending CN111175007A (en) | 2019-12-31 | 2019-12-31 | Blade surface flow visualization method based on HSV mode |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111175007A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116183157A (en) * | 2023-04-25 | 2023-05-30 | 太原理工大学 | Intelligent wind tunnel experimental device |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN205642795U (en) * | 2016-05-30 | 2016-10-12 | 北京金风科创风电设备有限公司 | Empty air flow field testing arrangement of blade |
| CN107423473A (en) * | 2017-04-26 | 2017-12-01 | 江苏大学 | The computational methods of coarse granule sliding velocity in a kind of pump |
| CN108953171A (en) * | 2018-07-27 | 2018-12-07 | 江苏大学 | A kind of the 3D-PIV measuring device and method of mixed-flow pump blade rim gap flow field |
| CN109409016A (en) * | 2018-12-13 | 2019-03-01 | 中国空气动力研究与发展中心计算空气动力研究所 | A kind of aero-engine compressor UNSTEADY FLOW method for visualizing |
| CN109751202A (en) * | 2019-03-08 | 2019-05-14 | 上海中认尚科新能源技术有限公司 | A kind of detection device and method for assessing wind power generation unit blade power enhancer performance |
-
2019
- 2019-12-31 CN CN201911410329.4A patent/CN111175007A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN205642795U (en) * | 2016-05-30 | 2016-10-12 | 北京金风科创风电设备有限公司 | Empty air flow field testing arrangement of blade |
| CN107423473A (en) * | 2017-04-26 | 2017-12-01 | 江苏大学 | The computational methods of coarse granule sliding velocity in a kind of pump |
| CN108953171A (en) * | 2018-07-27 | 2018-12-07 | 江苏大学 | A kind of the 3D-PIV measuring device and method of mixed-flow pump blade rim gap flow field |
| CN109409016A (en) * | 2018-12-13 | 2019-03-01 | 中国空气动力研究与发展中心计算空气动力研究所 | A kind of aero-engine compressor UNSTEADY FLOW method for visualizing |
| CN109751202A (en) * | 2019-03-08 | 2019-05-14 | 上海中认尚科新能源技术有限公司 | A kind of detection device and method for assessing wind power generation unit blade power enhancer performance |
Non-Patent Citations (2)
| Title |
|---|
| 张永刚: "透平叶栅气动特性实验研究", 《万方数据》 * |
| 王晓东 等: "低速轴流涡轮叶片层流分离流动的数值模拟方法比较", 《风机技术》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116183157A (en) * | 2023-04-25 | 2023-05-30 | 太原理工大学 | Intelligent wind tunnel experimental device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11549492B2 (en) | Method of condition monitoring one or more wind turbines and parts thereof and performing instant alarm when needed | |
| CN110261394A (en) | Online fan blade damages real-time diagnosis system and method | |
| US10378517B2 (en) | Method for replacing the blades of a wind turbine to maintain safe operation | |
| CA2883772C (en) | Method for replacing the blades of a wind turbine to maintain safe operation | |
| CN108894933A (en) | With losing method for catching again and system when by unmanned plane to blower blade tip tracing detection | |
| Vey et al. | Extracting quantitative data from tuft flow visualizations on utility scale wind turbines | |
| WO2021037447A1 (en) | Method and system for monitoring blades of a wind turbine | |
| CN113610749B (en) | Fan blade defect detection method based on neural network | |
| CN108915959A (en) | By unmanned plane to blower tip region detour detection method and system | |
| CN113759960A (en) | Unmanned aerial vehicle-based fan blade and tower barrel inspection identification system and method | |
| CN111175007A (en) | Blade surface flow visualization method based on HSV mode | |
| CN112598539B (en) | Wind power curve optimization calculation and outlier detection method for wind generating set | |
| CN108869196A (en) | By unmanned plane to base region detection method on rear side of blower and system | |
| CN112950634A (en) | Method, equipment and system for identifying damage of wind turbine blade based on unmanned aerial vehicle routing inspection | |
| CN205135913U (en) | String of a musical instrument locating template and setting angle of blade measurement system of wind turbine generator system blade | |
| CN117514646B (en) | Dynamic inspection analysis method and system for ground type fan blade | |
| GB2568676A (en) | Wind turbine blade orientation detection | |
| CN106778723B (en) | A kind of pneumatic equipment bladess surface image extracting method in complex background environment | |
| CN113565697A (en) | Impeller pneumatic unbalance optimization system and method based on laser and video measurement | |
| WO2023246062A1 (en) | Intelligent video-based electric power analysis and monitoring structure, system and method, and storage medium thereof | |
| CN112085694A (en) | Artificial intelligence automatic inspection wind energy fan blade system | |
| WO2023035708A1 (en) | Optimal position for wind turbine blade sound signal collection and selection method therefor | |
| CN116301652A (en) | Wind turbine generator online monitoring historical data cold-hot separation system | |
| CN115405473A (en) | Visual testing method and device for surface turbulence of wind turbine generator blade | |
| CN114299403A (en) | Electricity tower bolt detection method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200519 |
|
| RJ01 | Rejection of invention patent application after publication |