Blade surface icing morphology repeatability verification method
By measuring the icing height at selected feature points on the blade surface and establishing a benchmark database, the problem of repeatability verification of icing morphology on the blade surface was solved, thus improving the accuracy and economy of icing experiments.
Patent Information
- Application Number
- CN202511244704.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-02
- Publication Date
- 2025-11-04
AI Technical Summary
Existing technologies cannot ensure the repeatability of the icing morphology on the blade surface under the same operating conditions, resulting in inaccurate icing test results and high costs.
The icing height at selected feature points on the blade surface was measured using calipers to establish a baseline icing morphology feature database. The similarity of icing morphology was verified by the average icing height, reducing the reliance on three-dimensional scanning imaging equipment.
It improves the accuracy and economy of icing experiments, reduces the difficulty of measurement and the complexity of data processing, and reduces experimental costs.
Smart Images
Figure CN120890342A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of blade icing experiment, and particularly relates to a blade surface icing morphology repeatability verification method. BACKGROUND
[0002] Icing is generally defined as the freezing of supercooled water droplets on the body, engine, propeller or rotor and the formation of a large amount of ice, thereby disturbing the airflow.
[0003] When the aircraft flies in the atmosphere with the temperature near or below the freezing point and collides with supercooled water droplets, the wings, control surfaces and engine inlets of the aircraft will be iced. The loss of heat on the surface of the aircraft causes part or all of the water droplets to freeze before leaving the surface of the aircraft body. If all the supercooled water droplets freeze immediately when colliding, frost-like ice accumulations will be formed, which is called frost ice. If only part of the water droplets freeze immediately, and the remaining water flows along the surface of the aircraft or the existing ice surface and freezes downstream, bright ice accumulations will be formed, which is called glaze ice.
[0004] The amount, speed and shape of icing depend on factors such as meteorology and aerodynamics. First of all, the most important factors are liquid water content, temperature, wind speed, water droplet size, surface roughness, etc. Secondly, it depends on the type of cloud, the model of the aircraft and the type of icing protection system, etc.
[0005] In addition to being widely used in aircraft, blades are also widely used in fluid machines such as wind turbines, and the aerodynamic performance of the blades is directly related to the overall working efficiency of the fluid machine.
[0006] Under various natural environments, the blades of the fluid machine will be affected by factors such as sand, rain, snow and freezing rain. After a long period of accumulation or in the face of extreme bad weather, the aerodynamic surface of the blade will inevitably be adsorbed with mortar or frozen with ice, thereby reducing the working efficiency of the blade. Therefore, it is necessary to study the influence of blade surface icing on its performance.
[0007] In the current icing experiment, it is impossible to ensure that the blade surface icing morphology remains the same under the same working condition, thereby affecting the accuracy of the icing experiment results. In addition, the icing morphology is usually measured by a three-dimensional scanning imaging device, and the cost of the three-dimensional scanning imaging device is relatively high, thereby increasing the overall cost of the icing experiment, resulting in poor economy of the icing experiment. SUMMARY
[0008] In view of the problems in the prior art, the present application provides a blade surface icing morphology repeatability verification method, which verifies the blade surface icing morphology to test the similarity of the blade surface icing morphology under the same working condition, so as to lay a foundation for other measurement experiments in the icing experiment, reduce the icing experiment error, and improve the icing experiment result accuracy; when the blade surface icing morphology is verified, a three-dimensional scanning imaging device with high cost is not needed, only the selected feature point icing height is measured by using a lower-cost caliper, and the limited icing height feature points are used to represent the similarity of the blade surface icing morphology, so that the measurement difficulty and the complexity of subsequent data processing are effectively reduced, the icing experiment cost is greatly reduced, and the icing experiment economy is improved.
[0009] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme: a blade surface icing morphology repeatability verification method, comprising the following steps: Step one: select an icing experiment blade, determine the chord length and the span length of the blade, set an icing morphology feature section along the span length direction of the blade, set an icing morphology feature point on the icing morphology feature section along the chord length direction of the blade, and mark the icing morphology feature section and the icing morphology feature point on the blade surface according to the set position; Step two: determine the experimental working condition and issue an experimental outline; Step three: install the blade with the marked icing morphology feature section and icing morphology feature point on the icing experiment table; Step four: perform the icing experiment on the blade according to the first experimental working condition in the experimental outline, adopt a staged icing mode, and after each icing stage is ended, the icing height at the icing morphology feature point position is measured and recorded; Step five: repeat steps three and four, and the number of repetitions is not less than 3 times, until all the nondiscriminatory experiments are completed, and then all the nondiscriminatory experiment data are recorded and summarized; Step six: remove the icing on the blade surface to restore the blade to the initial state; Step seven: repeat steps three to five, and the difference lies in adjusting the experimental working condition until the blade icing experiment under different experimental working conditions is completed; Step eight: summarize the experimental data obtained in step seven to obtain the icing height average value of the icing morphology feature point position of the blade at different time stages under any same working condition, and establish a blade icing experiment reference icing morphology feature database and an icing time trend development curve based on the icing height average values; Step nine: repeat steps three and four, and the difference lies in performing other measurement experiments on the blade in the icing experiment; Step ten: compare the icing height measurement data obtained in step nine with the reference icing morphology feature database of the blade icing experiment in step eight, when the relative error of the icing height data is less than or equal to 10%, it is indicated that the blade surface icing morphology feature meets the similarity standard, and it is determined that other measurement experimental data is valid.
[0010] In step one, the number of icing morphology feature sections is 3-5, and the number of icing morphology feature points is 9-15.
[0011] In step four, the number of icing stages is 5-10, and the length of the icing stage is 0.5-1 hour.
[0012] In step four, after each icing stage ends, the blade is first transferred from the icing experiment table to the measurement table, and the icing height is measured by the caliper, and then the blade is installed back on the icing experiment table for continuous icing experiment.
[0013] The beneficial effects of the application are: The blade surface icing morphology repeatability verification method verifies the blade surface icing morphology to test the similarity of the blade surface icing morphology under the same working condition, so as to lay a foundation for other measurement experiments in the icing experiment, reduce the icing experiment error, and improve the icing experiment result accuracy; when verifying the blade surface icing morphology, a three-dimensional scanning imaging device with high cost is not needed, only the caliper with lower cost is used to measure the icing height at the selected feature points, and the limited icing height feature points are used to represent the similarity of the blade surface icing morphology, which effectively reduces the measurement difficulty and the complexity of subsequent data processing, greatly reduces the cost of the icing experiment, and improves the economy of the icing experiment. BRIEF DESCRIPTION OF DRAWINGS
[0014] Figure 1 is a schematic view of the icing morphology feature section and the icing morphology feature point of the blade surface; Figure 2 is Figure 1 is a cross-sectional view of A-A in the figure; In the figure, 1 is a blade, 2 is an icing morphology feature section, 3 is an icing morphology feature point, and 4 is icing. DETAILED DESCRIPTION
[0015] The application will be further described in detail below in combination with the drawings and specific embodiments.
[0016] A blade surface icing morphology repeatability verification method comprises the following steps: Step one: select the blade 1 for icing experiment, determine the chord length and span length of the blade 1, set the icing morphology characteristic section 2 along the span length direction of the blade 1, set the icing morphology characteristic point 3 on the icing morphology characteristic section 2 along the chord length direction of the blade 1, and mark the icing morphology characteristic section 2 and the icing morphology characteristic point 3 on the surface of the blade 1 according to the set position, as shown in Figure 1 、 2 ; Specifically, the number of icing morphology characteristic sections 2 is 3-5, and the number of icing morphology characteristic points 3 is 9-15. In this embodiment, the blade 1 is selected as a NACA0018 symmetric airfoil blade. Step two: determine the experimental conditions and issue the experimental outline. Step three: install the blade 1 with marked icing morphology characteristic section 2 and icing morphology characteristic point 3 on the icing experiment table. Step four: perform icing experiment on the blade 1 according to the first experimental condition in the experimental outline, and use the staged icing mode. After the end of each icing stage, the icing height at the position of the icing morphology characteristic point 3 is measured and recorded. Specifically, the number of icing stages is 5-10, and the duration of each icing stage is 0.5-1 hour. Specifically, after the end of each icing stage, the blade 1 is first transferred from the icing experiment table to the measurement table, and the icing height is measured by the caliper. After the measurement is completed, the blade 1 is installed back on the icing experiment table for continuous icing experiment. In this embodiment, the number of icing stages is set to 5, and the duration of each icing stage is set to 0.5 hour. Step five: repeat steps three and four for no less than 3 times until all non-discriminatory experiments are completed, and then record and summarize all non-discriminatory experimental data. Step six: remove the icing 4 on the surface of the blade 1 to restore the blade 1 to the initial state. Step seven: repeat steps three to five, with the difference being that the experimental conditions are adjusted until the icing experiment of the blade 1 under different experimental conditions is completed. Step eight: summarize the experimental data obtained in step seven to obtain the average icing height at the position of the icing morphology characteristic point 3 at different time stages of the blade 1 under any same condition, and establish the reference icing morphology characteristic database and the icing time trend development curve of the blade 1 icing experiment based on these average icing heights. Step nine: repeat steps three and four, with the difference being that other measurement experiments are performed on the blade 1 during the icing experiment. For example, the blade 1 can be subjected to aerodynamic force measurement experiment in icing experiment to obtain the aerodynamic force change of the blade 1 in the icing process. Step ten: compare the icing height measurement data obtained in step nine with the reference icing morphology feature database of the blade 1 icing experiment in step eight, when the relative error of the icing height data is less than or equal to 10%, it is indicated that the icing morphology feature of the blade 1 surface satisfies the similarity standard, and it is determined that other measurement experiment data is valid.
[0017] The scheme in the embodiment is not used to limit the protection scope of the present application, and equivalent implementation or changes without departing from the present application are included in the protection scope of the present application.
Claims
1. A method for verifying the repeatability of icing morphology on a blade surface, characterized in that, Includes the following steps: Step 1: Select blades for the icing experiment, determine the chord length and span of the blades, set the icing morphology characteristic section along the blade span direction, set the icing morphology characteristic points along the blade chord length direction on the icing morphology characteristic section, and mark the icing morphology characteristic section and icing morphology characteristic points on the blade surface according to the set positions. Step 2: Determine the experimental conditions and issue an experimental outline; Step 3: Install the blades marked with the characteristic cross-sections and points of the icing morphology onto the icing test platform; Step 4: Conduct an icing experiment on the blades according to the first experimental condition in the experimental outline. Use a staged icing mode. After each icing stage, measure and record the icing height at the characteristic points of the icing morphology. Step 5: Repeat steps 3 and 4 at least 3 times until all indiscriminate experiments are completed. Then record and summarize all indiscriminate experimental data. Step 6: Remove the ice from the surface of the blades to restore them to their initial state; Step 7: Repeat steps 3 to 5, the difference being that the experimental conditions are adjusted, until the blade icing experiment under different experimental conditions is completed; Step 8: Summarize the experimental data obtained in Step 7 to obtain the average ice height at the ice morphology feature points of the blade at different time stages under any identical working conditions. Based on these average ice heights, establish a benchmark ice morphology feature database and ice time trend curve for the blade ice experiment. Step Nine: Repeat Steps Three and Four, except that other measurement experiments are performed on the leaves during the freezing experiment; Step 10: Compare the icing height measurement data obtained in Step 9 with the baseline icing morphology feature database of the blade icing experiment in Step 8. If the relative error of the icing height data is ≤10%, it indicates that the icing morphology features of the blade surface meet the similarity standard, and the other measurement experimental data are deemed valid.
2. The method for verifying the repeatability of icing morphology on a blade surface according to claim 1, characterized in that: In step one, the number of ice morphology characteristic sections is 3 to 5, and the number of ice morphology characteristic points is 9 to 15.
3. The method for verifying the repeatability of icing morphology on a blade surface according to claim 1, characterized in that: In step four, there are 5 to 10 freezing stages, and the duration of each freezing stage is 0.5 to 1 hour.
4. The method for verifying the repeatability of icing morphology on a blade surface according to claim 1, characterized in that: In step four, after each icing stage is completed, the blade is first transferred from the icing test stand to the measuring stand, and the icing height is measured using calipers. After the measurement is completed, the blade is put back on the icing test stand to continue the icing experiment.