Inlet icing range test method, device, equipment and storage medium

Abstract

The present application relates to an inlet icing range test method, device, equipment and storage medium, and relates to the field of aircraft testing technology, and realizes icing tests under large intake flow conditions for large-sized aircraft. The method includes: obtaining the flow field characteristic distribution law corresponding to the aircraft to be tested under natural inflow conditions; reducing the aircraft to be tested according to a preset size ratio to obtain a test piece to be tested; the preset size ratio is obtained according to the size of the test section; calculating the wind tunnel inflow conditions of the test piece to be tested when the flow field characteristics inside and outside the inlet of the test piece in the test section meet the flow field characteristic distribution law; the flow field characteristics inside the inlet are determined by the intake simulation capacity of the test section; and performing an icing range test on the test piece to be tested according to the wind tunnel inflow conditions.

Description

Technical Field

[0001] The present application relates to the field of aircraft testing technology, and in particular to an air inlet icing range test method, device, equipment and storage medium. Background Art

[0002] When an aircraft encounters icing during flight, it may cause the flight control system to malfunction, endangering aviation safety. The icing range and thickness caused by the aircraft passing through different types of clouds are also different. In order to better deal with ice with different icing ranges and thicknesses and take appropriate de-icing measures in time, the icing range of the aircraft encountering clouds under different conditions can be tested in advance to provide a reference for actual flight.

[0003] When conducting icing tests on aircraft with oversized fuselages, it is currently difficult to simulate the icing range under conditions of large intake flow rates. Summary of the invention

[0004] The technical problem to be solved by the present application is: how to conduct icing tests under large air intake flow conditions for large-sized aircraft.

[0005] In a first aspect, an embodiment provides an inlet icing range test method, which is applied to electronic equipment, and the method includes: obtaining a flow field characteristic distribution law corresponding to a test aircraft under natural inflow conditions; reducing the test aircraft according to a preset size ratio to obtain a test piece to be tested; the preset size ratio is determined according to a test section size and a blockage ratio requirement; calculating the wind tunnel inflow condition of the test piece to be tested in the test section when the internal flow field characteristics of the inlet duct and the external flow field characteristics of the inlet duct of the test piece to be tested in the test section meet the flow field characteristic distribution law; the internal flow field characteristics of the inlet duct are determined by the intake simulation capacity of the test section; and performing an icing range test on the test piece to be tested according to the wind tunnel inflow condition.

[0006] In one embodiment, the flow field characteristics include the Mach number of the flow field, and obtaining the flow field characteristics distribution law corresponding to the aircraft to be tested under natural inflow conditions includes: obtaining the far-field inflow conditions corresponding to the natural inflow conditions; the far-field inflow conditions include inflow wind speed, temperature and ambient pressure; setting a calibration section for measuring the internal flow field of the inlet duct of the aircraft to be tested according to the streamline turning point formed by the fluid entering the inlet duct of the aircraft; calling a preset program to simulate the impact of the airflow on the aircraft to be tested according to the far-field inflow conditions, and calculating the far-field airflow Mach number of the aircraft to be tested under natural inflow conditions; calling a preset program to simulate the impact of the airflow on the aircraft to be tested according to the far-field inflow conditions, and calculating the internal airflow Mach number of the aircraft to be tested under natural inflow conditions based on the calibration section; calculating a first ratio of the far-field airflow Mach number to the internal airflow Mach number as the flow field characteristics distribution law.

[0007] In one embodiment, calculating the wind tunnel flow conditions of the test piece to be tested in the test section when the internal flow field characteristics and external flow field characteristics of the air inlet duct of the test piece to be tested in the test section conform to the flow field characteristic distribution law includes: calculating the wind tunnel flow conditions of the test piece to be tested in the test section when the second ratio of the Mach number of the internal airflow inlet duct of the test piece to be tested in the test section and the Mach number of the wind tunnel airflow is the same as the first ratio.

[0008] In one embodiment, the flow field characteristics include the pressure of the flow field, and the flow field characteristics distribution law also includes a target pressure curve of the inlet lip area of ​​the aircraft; the lip area refers to the part of the outer wall of the aircraft that diverts the far-field incoming flow to the end position; the end position corresponds to the position where the streamlines of different far-field incoming flows after the diversion begin to be parallel.

[0009] In one embodiment, the flow field characteristic distribution law also includes a first ratio of the Mach number of the airflow inside the inlet duct of the aircraft to the Mach number of the far-field airflow; after calculating whether the internal field flow field characteristics and the external field flow field characteristics of the test piece in the test section conform to the flow field characteristic distribution law, the method also includes: setting an initial pressure curve of the inlet duct lip area of ​​the test piece according to the first ratio and the far-field incoming flow conditions; collecting the actual pressure distribution of the inlet duct lip area of ​​the test piece by a pressure measuring device set in the inlet duct lip area of ​​the test piece; and collecting the actual pressure distribution of the inlet duct lip area of ​​the test piece according to the actual pressure curve and the target pressure. The difference between the pressure curves is obtained, and the intake flow rate or wind tunnel inflow condition of the specimen to be tested in the test section is adjusted on the basis of the initial pressure curve until the difference between the actual pressure curve and the target pressure curve is less than a preset threshold; the wind tunnel inflow condition and the target intake flow rate of the specimen to be tested in the test section are obtained when the difference between the actual pressure curve and the target pressure curve is less than the preset threshold; and an icing range test is performed on the specimen to be tested according to the wind tunnel inflow condition, including: performing an icing range test on the specimen to be tested according to the adjusted wind tunnel inflow condition and the target intake flow rate.

[0010] In one embodiment, an icing range test is performed on the test piece according to the adjusted wind tunnel inflow condition and the target air intake flow rate, including: obtaining water droplet correction impact parameters of the test aircraft under natural inflow conditions; adjusting the water droplet diameter according to the wind tunnel inflow condition with the goal of maintaining the water droplet correction impact parameters to obtain a target water droplet diameter; and performing an icing range test on the test piece according to the adjusted wind tunnel inflow condition and the target water droplet diameter.

[0011] In one embodiment, before performing the step of adjusting the initial air intake flow rate or the initial wind tunnel flow condition of the test piece in the test section based on the initial pressure curve, the method further includes:

[0012] According to the preset initial intake air flow rate of the test piece in the test section, when a second ratio of the Mach number of the airflow inside the air inlet duct of the test piece in the test section to the Mach number of the airflow in the wind tunnel is calculated to be the same as the first ratio, the initial wind tunnel inflow condition of the test piece in the test section;

[0013] Alternatively, based on the preset initial wind tunnel flow conditions of the specimen to be tested in the test section, the initial intake flow rate of the specimen to be tested in the test section is calculated when a second ratio of the Mach number of the airflow inside the inlet duct of the specimen to be tested in the test section to the Mach number of the wind tunnel airflow is the same as the first ratio.

[0014] In a second aspect, an embodiment provides an inlet icing range test device, the device comprising:

[0015] The flow field characteristic acquisition module is used to obtain the flow field characteristic distribution law corresponding to the aircraft under test under natural flow conditions;

[0016] A scaling module is used to reduce the aircraft to be tested according to a preset size ratio to obtain a test piece to be tested; the preset size ratio is determined according to the test section size and the blocking ratio requirement;

[0017] A calculation module, used for calculating the wind tunnel flow conditions of the test piece to be tested in the test section when the flow field characteristics inside the air inlet duct and the flow field characteristics outside the air inlet duct of the test piece to be tested in the test section meet the flow field characteristics distribution law; the flow field characteristics inside the air inlet duct are determined by the intake simulation capability of the test section;

[0018] The test module is used to perform an icing range test on the test piece according to the wind tunnel flow conditions.

[0019] In a third aspect, an embodiment of the present application further provides a computing device, which includes a processor and a memory, a computer program that can be run on the processor in the memory, and the steps in the aforementioned method embodiment are implemented when the processor executes the program at runtime.

[0020] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, which stores a program executable by a processor, and the program executable by the processor is used to implement the aforementioned method when the program is executed by the processor.

[0021] The beneficial effects of this application are:

[0022] The wind tunnel inflow conditions obtained in the above manner follow the distribution of the airflow inside and outside the air inlet of the aircraft under natural inflow conditions; and the reduction ratio of the aircraft and the test piece set on this basis is obtained according to the air intake flow rate that the test section can provide. Therefore, the wind tunnel inflow conditions of the test piece obtained by this calculation can not only restore the air fluid environment encountered by the aircraft to be tested under natural conditions, but also realize the simulation of large air intake flow rate. At the same time, the test piece obtained by reducing the size of the aircraft can be placed in the test section, solving the problem that it is difficult for large-sized aircraft to undergo icing tests through icing wind tunnels. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a flow chart of the steps of the inlet icing range test method proposed in the embodiment of the present application;

[0024] Figure 2 is a side view of an aircraft air inlet given in an example of the present application;

[0025] Figure 3 This is an axial view of an aircraft air inlet provided as an example of the present application;

[0026] Figure 4 is a side view of an aircraft air inlet provided in another example of the present application;

[0027] Figure 5 It is a functional module diagram of the air inlet icing range test device proposed in the embodiment of the present application;

[0028] Figure 6 A schematic diagram of the structure of a computing device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0029] The present application is further described in detail below by specific embodiments in conjunction with the accompanying drawings. Wherein similar elements in different embodiments adopt associated similar element numbers. In the following embodiments, many detailed descriptions are intended to enable the present application to be better understood. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, and methods. In some cases, some operations related to the present application are not shown or described in the specification, in order to avoid the core part of the present application being overwhelmed by too much description, and for those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0030] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate manner to form various implementations. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for the purpose of clearly describing a certain embodiment and are not meant to be a required sequence, unless otherwise specified that a certain sequence must be followed.

[0031] There are the following difficulties in conducting icing tests under specific intake conditions on larger aircraft in icing wind tunnels: the current ice wind tunnel test section size and intake flow simulation capabilities cannot meet the test requirements of the air inlet ducts of such aircraft.

[0032] In view of the above problems, an embodiment of the present application proposes a method for testing the range of icing in an air inlet. According to the test section size and the blockage ratio requirements, the aircraft is proportionally reduced to obtain a test piece. On this basis, the embodiment of the present application predicts the distribution law of the flow field characteristics of the aircraft passing through a specific cloud layer under natural conditions through simulation software. According to the flow field characteristic distribution law, based on the maximum inlet air flow rate provided by the icing wind tunnel, the wind tunnel inflow condition of the icing wind tunnel is adjusted. The flow field characteristic pressure corresponding to the wind tunnel inflow condition and the inlet air flow rate conforms to the flow field characteristic distribution law of the aircraft passing through a specific cloud layer under natural conditions, thereby solving the problem that it is difficult to conduct icing tests on large-sized aircraft under large inlet flow conditions.

[0033] Figure 1 is a flow chart of the steps of the inlet icing range test method proposed in the embodiment of the present application, such as Figure 1 As shown, the steps include:

[0034] Step S11: Obtain the flow field characteristic distribution law corresponding to the aircraft to be tested under natural flow conditions.

[0035] Aircraft under natural oncoming conditions refers to: the impact on the aircraft when it passes through a specific type of cloud in a natural scene.

[0036] For example, a specific type of cloud layer is an incoming cloud layer with a droplet diameter of MVD and a liquid water content of LWC. By setting sensors, the wind speed V, ambient pressure P and other parameters to which the aircraft is subjected when passing through the specific incoming cloud layer are measured or calibrated in advance, and then the pressure distribution law to which the aircraft is subjected under the wind speed V, ambient pressure P and other parameters is simulated and calculated.

[0037] For example, numerical simulation software can be used to simulate the fluid mechanics of an aircraft of original size, and a cloud model with parameters such as wind speed V and ambient pressure P can be constructed to simulate the distribution law of flow field characteristics of an aircraft of original size passing through a corresponding cloud layer under natural flow conditions.

[0038] Through the above simulation, we can obtain the impact of air fluid on the aircraft under ideal conditions without the influence of icing on the wind tunnel wall.

[0039] In one example of the present application, the flow field characteristic distribution law may refer to the ratio of the Mach number of the airflow inside the aircraft inlet and the Mach number of the far-field airflow.

[0040] Since the aircraft passes through the cloud layer, the temperature and pressure of the cloud layer vary with different conditions, so an example of the present application uses the Mach number to represent the flow field characteristics around the aircraft.

[0041] This application provides an example of specific sub-steps S111-S115 for executing step S11:

[0042] S111: Obtaining far-field incoming flow conditions corresponding to the natural incoming flow conditions; the far-field incoming flow conditions include incoming flow wind speed, temperature and ambient pressure.

[0043] For example, if the specific cloud layer is an incoming cloud layer with a droplet diameter of MVD and a liquid water content of LWC, the far-field incoming flow conditions of the aircraft passing through the incoming cloud layer with a droplet diameter of MVD and a liquid water content of LWC are pre-measured or calibrated by setting sensors: wind speed , far-field temperature , far-field environmental pressure The parameters related to the far-field flow are marked with a subscript of ∞, and the parameters related to the flow inside the inlet are marked with The subscripts of the corresponding flow parameters of the aircraft under natural flow conditions are marked The subscripts of the test pieces in the wind tunnel are marked with The subscript of stands for reference (Reference), and S stands for scale (Scale).

[0044] S112: According to the streamline turning point formed by the fluid entering the air inlet of the aircraft, a calibration section for measuring the flow field inside the air inlet of the aircraft to be measured is set.

[0045] Figure 2 This is a side view of an aircraft air inlet given in an example of the present application. Figure 3 This is an example of an aircraft inlet axial view given in the present application, such as Figure 2 and Figure 3As shown, the inlet divides the far-field flow, a part of the air fluid enters the inlet, and the other part of the air fluid flows outside the inlet relative to the aircraft. The flow curve of the air fluid entering the inlet is related to the inlet lip. Therefore, the streamline turning point formed by the gas entering the inlet of the aircraft can indicate that the air fluid has entered the interior of the inlet, and the calibration section has been set at this turning point. The Mach number of the calibration section is less affected by the environment after ice formation inside the inlet duct, and it is more accurate to use the Mach number of the calibration section as the Mach number of the inlet duct.

[0046] S113: calling a preset program to simulate the impact of airflow on the aircraft to be tested according to the far-field incoming flow condition, and calculating the far-field airflow Mach number of the aircraft to be tested under the natural incoming flow condition.

[0047] Call the pre-set fluid dynamics numerical simulation program (CFD) according to the known Figure 2 Far-field flow conditions and far-field wind speed shown , far-field temperature , far-field environmental pressure , calculate the far-field airflow Mach number .

[0048] S114: calling a preset program to simulate the impact of airflow on the aircraft to be tested according to the far-field incoming flow condition, and calculating the internal airflow Mach number of the aircraft to be tested under the natural incoming flow condition based on the calibrated cross section.

[0049] Specifically, the average Mach number to which the calibration cross section is subjected can be calculated.

[0050] Call the pre-set fluid dynamics numerical simulation program (CFD) to calculate the far-field wind speed based on the known far-field flow conditions. , far-field temperature , far-field environmental pressure , calculate the Mach number of the internal airflow of the aircraft under natural conditions .

[0051] S115: Calculate a first ratio of the far-field airflow Mach number to the internal airflow Mach number as the flow field characteristic distribution law.

[0052] Calculate the ratio of the far-field airflow Mach number of the aircraft to the internal airflow Mach number of the aircraft under natural flow conditions / =ε, taking this as the standard, under the condition that the internal flow rate of the air inlet provided by the icing wind tunnel is constant, the wind tunnel inflow conditions of the icing wind tunnel test are calculated, and it is determined that the ratio of the wind tunnel airflow Mach number of the test piece in the icing wind tunnel to the internal airflow Mach number of the test piece is equal to ε, thereby ensuring that the flow field of the scaled-down test piece in the test section is consistent with the flow field of the aircraft under the natural inflow conditions, so that the test environment of the scaled-down test piece can restore the air and fluid environment corresponding to the aircraft under natural conditions, and the airflow inside the air inlet of the test piece will not be too large relative to the airflow outside the air inlet, or the airflow inside the air inlet of the test piece will not be too small relative to the airflow outside the air inlet.

[0053] Step S12: reducing the aircraft to be tested according to a preset size ratio to obtain a test piece to be tested.

[0054] The preset size ratio is determined according to the test section size and the blocking ratio requirements. The preset size ratio is determined according to the ratio of the projected area of ​​the model after reduction to the cross-sectional area of ​​the test section meeting a specific value.

[0055] Step S13: Calculating the wind tunnel flow conditions of the test piece in the test section when the flow field characteristics inside the air inlet duct and the flow field characteristics outside the air inlet duct of the test piece in the test section meet the flow field characteristic distribution law.

[0056] The flow field characteristics inside the air inlet duct are determined by the air intake simulation capability of the test section; generally, the flow field characteristics inside the air inlet duct can be set according to the air flow intensity inside the air inlet duct of the test piece extracted by the icing wind tunnel fan.

[0057] In one example, when calculating that the internal flow field characteristics and the external flow field characteristics of the inlet duct of the test piece in the test section conform to the flow field characteristic distribution law, the wind tunnel flow conditions of the test piece in the test section include:

[0058] When a second ratio of the inner field airflow Mach number and the outer field airflow Mach number of the test piece in the test section is calculated to be the same as the first ratio, the wind tunnel incoming flow condition of the test piece in the test section.

[0059] Continue to refer Figure 2 , according to the airflow intensity inside the air inlet of the test piece extracted by the icing wind tunnel fan, determine the air inlet flow of the test piece in the icing wind tunnel , according to the intake flow , calculate the Mach number of the internal airflow of the test piece in the icing wind tunnel , and then according to the ratio of the aircraft's far-field airflow Mach number to the aircraft's internal airflow Mach number / = ε, and The wind tunnel airflow Mach number of the test piece corresponding to the wind tunnel inflow condition of the test piece in the test section is calculated. , further based on the wind tunnel airflow Mach number of the test piece , set the wind tunnel flow conditions of the test piece in the icing wind tunnel .

[0060] Step S14: performing an icing range test on the test piece according to the wind tunnel flow conditions.

[0061] The wind tunnel inflow conditions obtained in the above manner follow the difference between the internal flow field characteristics of the air inlet and the external airflow field characteristics of the aircraft under natural inflow conditions. Therefore, the wind tunnel inflow conditions of the test piece obtained by this calculation can not only restore the air fluid environment corresponding to the aircraft to be tested under natural conditions, but also simulate the large inlet flow rate. At the same time, the test piece obtained by reducing the size of the aircraft can be placed in the test section, solving the problem that it is difficult for large-sized aircraft to undergo icing tests through icing wind tunnels.

[0062] Furthermore, the embodiments of the present application also propose: in addition to the ratio of the Mach number of the airflow inside the inlet duct to the Mach number of the far-field airflow, which can represent the distribution law of the flow field characteristics of the aircraft in an incoming flow environment, the target pressure curve of the inlet lip area of ​​the aircraft can also represent the distribution law of the flow field characteristics of the aircraft in an incoming flow environment.

[0063] The lip area refers to the portion of the outer wall of the aircraft that diverts the far-field incoming flow to the end position; the end position corresponds to the position where the streamlines of different far-field incoming flows after diversion begin to be parallel.

[0064] When the airflow encounters the aircraft inlet, it is split at the inlet lip position, and the streamline of the air fluid changes, and the streamline direction follows the fuselage curve in the lip area.

[0065] Figure 4 This is another example of the present application in which a side view of the aircraft air intake is given, referring to Figure 4 The dotted line portion indicates the inlet lip. The air streamlines flow in parallel to the inlet lip area, diverge at the position of the inlet lip area, and the diverged air streamlines become parallel again after passing through the inlet lip area.

[0066] The pressure distribution of the lip area of ​​the aircraft under natural inflow conditions is measured, and pressure measuring holes are set at preset distances at the lip position of the test piece. The test piece with the pressure measuring holes is placed in the test section, and the air pipes of the pressure measuring holes are connected to the scanning valve to collect the pressure data of the lip area. The pressure distribution curve of the lip area of ​​the test piece is drawn or calculated to compare whether the actual pressure curve of the test piece is consistent with the target pressure curve. When the actual pressure curve of the test piece is consistent with the target pressure curve, it can be determined that the test environment of the test piece to be tested has restored the airflow impact environment encountered by the aircraft to be tested when passing through a specific inflow cloud layer in a 1:1 manner.

[0067] Based on the above concept, another method for performing an inlet icing range test proposed in an embodiment of the present application includes the following steps:

[0068] S21: Obtaining a flow field characteristic distribution law corresponding to the aircraft under test under natural inflow conditions; one of the flow field characteristic distribution laws is a first ratio of the Mach number of the airflow inside the aircraft's inlet and the Mach number of the far-field airflow.

[0069] S22: reducing the aircraft to be tested according to a preset size ratio to obtain a test piece to be tested.

[0070] S23: Calculating the wind tunnel flow conditions of the test piece in the test section when the flow field characteristics inside the air inlet duct and the flow field characteristics outside the air inlet duct of the test piece in the test section meet the flow field characteristic distribution law.

[0071] Executing S23 includes sub-steps:

[0072] S231: Collecting an actual pressure curve of the air intake lip area of ​​the test piece by means of a pressure measuring device disposed in the air intake lip area of ​​the test piece.

[0073] The pressure measuring device includes a pressure measuring hole in the lip area, and the air pipe is connected to the scanning valve through the pressure measuring hole to collect the actual pressure in the lip area of ​​the air inlet of the test piece.

[0074] According to the preset initial intake flow rate and the pre-obtained initial wind tunnel flow conditions of the intake duct, the wind tunnel simulation flow parameters are set, and the initial pressure curve of the lip area is collected based on the wind tunnel simulation flow parameters.

[0075] The initial intake flow rate and the initial wind tunnel flow conditions are used to determine the starting point for adjusting the actual pressure curve. The more accurate the initial pressure curve is, that is, the more the initial pressure curve satisfies the flow field characteristic distribution law, the fewer steps the electronic device needs to take to adjust the actual pressure curve through the intake flow rate or wind tunnel flow conditions.

[0076] Furthermore, the embodiments of the present application also provide different ways to determine the initial wind tunnel flow conditions or initial intake flow rate of the test section, so that the internal flow field characteristics of the air inlet duct and the external flow field characteristics of the air inlet duct in the test section can be made to conform to the flow field characteristic distribution law as much as possible under certain conditions with the initial intake flow rate and the initial wind tunnel flow conditions. Subsequently, the wind tunnel simulation flow parameters are set according to the initial wind tunnel flow conditions and the initial intake flow rate, and then the initial pressure curve of the lip area is collected based on the wind tunnel simulation flow parameters to ensure that the initial pressure curve approaches the flow field characteristic distribution law from the beginning, reduce the adjustment steps, and provide a basis for calculating the wind tunnel flow conditions:

[0077] According to the preset initial intake air flow rate of the test piece in the test section, when a second ratio of the Mach number of the airflow inside the air inlet duct of the test piece in the test section to the Mach number of the airflow in the wind tunnel is calculated to be the same as the first ratio, the initial wind tunnel inflow condition of the test piece in the test section;

[0078] Alternatively, based on the preset initial wind tunnel flow conditions of the specimen to be tested in the test section, the initial intake flow rate of the specimen to be tested in the test section is calculated when a second ratio of the Mach number of the airflow inside the inlet duct of the specimen to be tested in the test section to the Mach number of the wind tunnel airflow is the same as the first ratio.

[0079] Among them, the specific implementation process of adjusting the initial intake flow rate of the intake duct of the test section is given;

[0080] S301: Obtaining the corresponding air intake flow rate of the air intake duct of the aircraft to be tested under natural inflow conditions.

[0081] S302: Determine the initial air intake flow rate of the air intake duct of the test piece in the test section based on the preset size ratio, the first ratio, and the air intake flow rate of the air intake duct corresponding to the natural flow condition of the aircraft to be tested.

[0082] S303: According to the difference between the actual pressure curve and the target pressure curve, on the basis of the initial pressure curve, the intake flow rate of the test piece to be tested in the test section is adjusted with the initial intake flow rate of the intake duct as the starting point.

[0083] S232: According to the difference between the actual pressure curve and the target pressure curve, the air intake flow rate or wind tunnel flow condition of the test piece in the test section is adjusted on the basis of the initial pressure curve until the difference between the actual pressure curve and the target pressure curve is less than a preset threshold.

[0084] It is known that by adjusting the intake flow rate or the wind tunnel flow conditions in the test section, the actual pressure curve will change. When the actual pressure curve changes to the point where the difference between it and the target pressure curve is minimal, or when the actual pressure curve changes to the point where it is consistent with the target pressure curve, the intake flow rate or the wind tunnel flow conditions are no longer adjusted. At this time, the internal flow field characteristics of the air inlet duct and the external flow field characteristics of the air inlet duct of the test piece to be tested in the test section conform to the flow field characteristic distribution law.

[0085] S233: When the difference between the actual pressure curve and the target pressure curve is less than a preset threshold, the wind tunnel flow condition and the target air intake flow rate of the test piece in the test section are obtained.

[0086] The preset threshold value can be set according to actual conditions. If the preset threshold value is set to 0, when the actual pressure curve is consistent with the target pressure curve, the intake flow rate in the corresponding test section is determined to be the target intake flow rate.

[0087] Alternatively, the preset threshold value may be set according to actual conditions. If the preset threshold value is set to 0, when the actual pressure curve is consistent with the target pressure curve, the corresponding test section wind speed is determined to be the target test section wind speed.

[0088] For example, when the adjustment starts, the initial pressure curve is the actual pressure curve, and the difference between the initial pressure curve and the target pressure curve is calculated. The air intake flow or wind speed of the test piece in the test section is adjusted according to the difference. The actual pressure curve is collected, and then the actual pressure curve is compared to see if it is consistent with the target pressure curve. If they are consistent, it is determined that the internal field wind speed at this time is the target air intake flow or target test section wind speed. If they are inconsistent, the difference between the actual pressure curve and the target pressure curve is continued to be calculated, and the internal field wind speed of the test piece in the test section is adjusted according to the difference.

[0089] S234: performing an icing range test on the test piece according to the adjusted wind tunnel inflow condition and the target air intake flow rate.

[0090] The lip pressure distribution formed by the impact of the test piece with the adjusted wind tunnel oncoming conditions is consistent with the lip pressure distribution formed when the aircraft is impacted by the oncoming air through a specific cloud layer under natural conditions. Therefore, by conducting icing tests on the test piece based on the adjusted wind tunnel oncoming conditions, a 1:1 icing impact range of the original aircraft can be obtained.

[0091] The embodiment of the present application also provides a method for calculating the diameter of a water droplet. When executing step S234 or step S14, the diameter of the water droplet is corrected, and an icing range test is performed based on the corrected diameter of the water droplet.

[0092] Changes in wind speed cause changes in the direction and speed of water droplets in the clouds. Therefore, in icing tests, the water droplet diameter can be corrected to control the speed and direction of water droplets without being affected by wind speed.

[0093] The process of correcting the droplet diameter includes:

[0094] Obtaining water droplet correction impact parameters of the aircraft under test under natural flow conditions;

[0095] With the goal of maintaining the water droplet modified impact parameter, the water droplet diameter is adjusted according to the wind tunnel incoming flow condition to obtain a target water droplet diameter;

[0096] After the water drop correction is executed, the icing range test is performed on the test piece according to the adjusted wind tunnel flow condition and the target water drop diameter.

[0097] The pre-set fluid dynamics numerical simulation program (CFD) is called to simulate the water droplet correction impact parameter K of the aircraft under the natural flow condition. The water droplet correction impact parameter K is related to the flow velocity. After obtaining the water droplet correction impact parameter K, the correction function K= , where MVD is the water droplet diameter, represents the target wind tunnel inflow velocity, given K and According to other embodiments of the present application, the target wind tunnel inflow velocity is determined by the equality of the first ratio and the second ratio, or based on the difference between the target pressure curve and the actual pressure curve of the lip area of ​​the test piece, the wind tunnel inflow velocity of the test piece in the test section is The adjusted target wind tunnel inflow wind speed is obtained based on the debugging.

[0098] Based on the inlet icing range test method proposed in the above embodiment, a test environment consistent with the air action encountered by the aircraft to be tested in the natural incoming flow impact is restored. The test environment determines icing conditions such as the inlet internal wind speed, the external incoming flow wind speed, the water droplet diameter parameters, and the inlet flow parameters. The above icing conditions can make the airflow action on the test piece in the icing wind tunnel consistent with the airflow action on the aircraft in the natural environment, and can make the range of water droplet action on the test piece in the icing wind tunnel consistent with the range of water droplet action on the aircraft in the natural environment. Therefore, an accurate icing range can be obtained by performing an icing test based on the above parameters.

[0099] Figure 5 is a functional module diagram of the air inlet icing range test device proposed in the embodiment of the present application, such as Figure 5 As shown, the device comprises:

[0100] The flow field characteristic acquisition module 51 is used to obtain the flow field characteristic distribution law corresponding to the aircraft under test under the natural flow condition;

[0101] The scaling module 52 is used to scale down the aircraft to be tested according to a preset size ratio to obtain a test piece to be tested; the preset size ratio is determined according to the test section size and the blocking ratio requirement;

[0102] A calculation module 53 is used to calculate the wind tunnel flow conditions of the test piece to be tested in the test section when the flow field characteristics inside the air inlet duct and the flow field characteristics outside the air inlet duct of the test piece to be tested in the test section meet the flow field characteristics distribution law; the flow field characteristics inside the air inlet duct are determined by the intake simulation capability of the test section;

[0103] The test module 54 is used to perform an icing range test on the test piece according to the wind tunnel flow conditions.

[0104] Figure 5 The inlet icing range test device provided in the embodiment shown can be used to perform the present invention. Figures 1 to 4 The technical solution of the method embodiment shown, its implementation principle and technical effects can be further referred to the relevant description in the method embodiment.

[0105] Optionally, the flow field characteristic includes the Mach number of the flow field, and the pressure distribution acquisition module includes:

[0106] The inflow acquisition submodule is used to obtain the far-field inflow conditions corresponding to the natural inflow conditions; the far-field inflow conditions include inflow wind speed, temperature and ambient pressure;

[0107] A cross-section setting submodule, used for setting a calibration cross-section for measuring the flow field inside the air inlet of the aircraft to be tested according to a streamline turning point formed by the fluid entering the air inlet of the aircraft;

[0108] A program calling submodule is used to call a preset program to simulate the impact of airflow on the aircraft to be tested according to the far-field incoming flow condition, and calculate the far-field airflow Mach number of the aircraft to be tested under the natural incoming flow condition;

[0109] The program calling submodule is further used to call a preset program to simulate the impact of airflow on the aircraft to be tested according to the far-field incoming flow condition, and calculate the internal airflow Mach number of the aircraft to be tested under the natural incoming flow condition based on the calibrated cross section;

[0110] The calculation submodule is used to calculate a first ratio of the far-field airflow Mach number to the internal airflow Mach number as the flow field characteristic distribution law.

[0111] Optionally, the calculation module is specifically used to calculate the wind tunnel incoming flow condition of the test piece to be tested in the test section when a second ratio of the airflow Mach number inside the inlet duct of the test piece to the wind tunnel airflow Mach number in the test section is the same as the first ratio.

[0112] Optionally, the pressure distribution law further includes a first ratio of the Mach number of the airflow inside the inlet of the aircraft to the Mach number of the far-field airflow; and the device further includes:

[0113] A pressure curve setting module, used for setting an initial pressure curve of the inlet lip area of ​​the test piece according to the first ratio and the far-field incoming flow condition;

[0114] A collection module, used to collect the actual pressure distribution of the air intake lip area of ​​the test piece through a pressure measuring device arranged in the air intake lip area of ​​the test piece;

[0115] A first wind speed adjustment module, used for adjusting the air intake flow of the test piece to be tested in the test section based on the initial pressure curve according to the difference between the actual pressure curve and the target pressure curve, or adjusting the wind speed of the test piece to be tested in the test section based on the initial pressure curve until the difference between the actual pressure curve and the target pressure curve is less than a preset threshold;

[0116] A wind speed acquisition module, used to obtain the wind tunnel inflow condition and target air intake flow rate of the test piece in the test section when the difference between the actual pressure curve and the target pressure curve is less than a preset threshold;

[0117] The test module is specifically used to perform an icing range test on the test piece according to the adjusted wind tunnel inflow condition and the target air intake flow rate.

[0118] Optionally, the test module further includes:

[0119] The water droplet diameter correction submodule is used to obtain the water droplet correction impact parameters of the aircraft under the natural flow condition; with the goal of maintaining the water droplet correction impact parameters, adjust the water droplet diameter according to the wind tunnel flow condition to obtain the target water droplet diameter;

[0120] The test module is specifically used to perform an icing range test on the test piece according to the adjusted wind tunnel inflow condition and the target water droplet diameter.

[0121] Optionally, the device further comprises:

[0122] an initial inflow adjustment module, for calculating, based on a preset initial inflow flow rate of the test piece to be tested in the test section, an initial wind tunnel inflow condition of the test piece to be tested in the test section when a second ratio of the Mach number of the airflow inside the inlet duct of the test piece to be tested in the test section to the Mach number of the airflow in the wind tunnel is the same as the first ratio;

[0123] An initial air intake adjustment module is used to calculate the initial air intake flow rate of the test piece to be tested in the test section when a second ratio of the Mach number of the airflow inside the inlet duct of the test piece to be tested in the test section to the Mach number of the wind tunnel airflow is the same as the first ratio based on the preset initial wind tunnel flow conditions of the test piece to be tested in the test section.

[0124] Regarding the various modules / units included in the various devices described in the above embodiments, they can be software modules / units, or hardware modules / units, or they can be partially software modules / units and partially hardware modules / units. For example, for various devices applied to or integrated in a chip, the various modules / units included therein can all be implemented in the form of hardware such as circuits, or at least some of the modules / units can be implemented in the form of software programs, which run on a processor integrated inside the chip, and the remaining modules / units can be implemented in the form of hardware such as circuits; for various devices applied to or integrated in a chip module, the various modules / units included therein can all be implemented in the form of hardware such as circuits, and different modules / units can be located in the same component of the chip module (such as a chip, circuit module, etc.) or in different components, or at least some of the modules / units can be implemented in the form of software programs. The software program may be implemented in the form of a program, which runs on a processor integrated in the chip module, and the remaining modules / units may be implemented in the form of hardware such as circuits; for each device applied to or integrated in the electronic terminal device, each module / unit contained therein may be implemented in the form of hardware such as circuits, and different modules / units may be located in the same component (for example, a chip, a circuit module, etc.) or in different components in the electronic terminal device, or at least some modules / units may be implemented in the form of a software program, which runs on a processor integrated in the electronic terminal device, and the remaining (if any) modules / units may be implemented in the form of hardware such as circuits.

[0125] Figure 6 A structural diagram of a computing device provided in an embodiment of the present application, the computing device 600 includes a processor 610, a memory 611, and a computer program stored in the memory 611 and executable on the processor 610. The processor 610 implements the steps in the aforementioned method embodiment when executing the program. The computing device provided in the embodiment can be used to execute the technical solution of the method embodiment shown above, and its implementation principle and technical effects can be further referred to the method.

[0126] In one embodiment of the present application, a computer storage medium is provided, on which a program is stored. The stored program includes a method that can be loaded by a processor and process any of the above embodiments.

[0127] Those skilled in the art will appreciate that all or part of the functions of the various methods in the above-mentioned embodiments can be implemented by hardware or by computer programs. When all or part of the functions in the above-mentioned embodiments are implemented by computer programs, the program can be stored in a computer-readable storage medium, and the storage medium can include: read-only memory, random access memory, disk, optical disk, hard disk, etc., and the program is executed by a computer to implement the above-mentioned functions. For example, the program is stored in the memory of the device, and when the program in the memory is executed by the processor, all or part of the above-mentioned functions can be implemented. In addition, when all or part of the functions in the above-mentioned embodiments are implemented by computer programs, the program can also be stored in a storage medium such as a server, another computer, disk, optical disk, flash disk or mobile hard disk, and can be downloaded or copied and saved in the memory of the local device, or the system of the local device is updated, and when the program in the memory is executed by the processor, all or part of the functions in the above-mentioned embodiments can be implemented.

[0128] The above specific examples are used to illustrate the present application, which is only used to help understand the present application and is not intended to limit the present application. For technicians in the technical field to which the present application belongs, they can also make some simple deductions, deformations or substitutions based on the ideas of the present application.

Claims

1. An inlet icing range test method, characterized in that: The method comprises: Obtain the distribution law of flow field characteristics corresponding to the aircraft under test under natural flow conditions; The aircraft to be tested is reduced in size according to a preset size ratio to obtain a test piece to be tested; the preset size ratio is determined according to the test section size and the blocking ratio requirement; Calculating the wind tunnel flow conditions of the test piece in the test section when the flow field characteristics inside the air inlet duct and the flow field characteristics outside the air inlet duct of the test piece in the test section meet the flow field characteristics distribution law; the flow field characteristics inside the air inlet duct are determined by the intake simulation capability of the test section; Performing an icing range test on the test piece according to the wind tunnel inflow conditions; The flow field characteristics include the Mach number of the flow field, and the method of obtaining the distribution law of the flow field characteristics corresponding to the aircraft under test under natural incoming flow conditions includes: Obtaining far-field incoming flow conditions corresponding to the natural incoming flow conditions; the far-field incoming flow conditions include incoming flow wind speed, temperature and ambient pressure; According to the streamline turning point formed by the fluid entering the air inlet of the aircraft, a calibration section for measuring the flow field inside the air inlet of the aircraft to be tested is set; Calling a preset program to simulate the impact of airflow on the aircraft to be tested according to the far-field incoming flow condition, and calculating the far-field airflow Mach number of the aircraft to be tested under the natural incoming flow condition; Calling a preset program to simulate the impact of airflow on the aircraft to be tested according to the far-field incoming flow condition, and calculating the internal airflow Mach number of the aircraft to be tested under the natural incoming flow condition based on the calibrated cross section; Calculating a first ratio of the far-field airflow Mach number to the internal airflow Mach number as the flow field characteristic distribution law; And / or, the flow field characteristics include the pressure of the flow field, and the flow field characteristics distribution law also includes a target pressure curve of the lip area of ​​the aircraft's air inlet; the lip area refers to the outer wall portion of the aircraft that diverts the far-field incoming flow to the end position; the end position corresponds to the position where the streamlines of different far-field incoming flows after diversion begin to be parallel; The flow field characteristic distribution law also includes a first ratio of the Mach number of the airflow inside the inlet of the aircraft to the Mach number of the far-field airflow; the method also includes: By means of a pressure measuring device disposed at the air inlet lip area of ​​the test piece, an actual pressure curve of the air inlet lip area of ​​the test piece is collected; When calculating that the flow field characteristics inside the air inlet duct and the flow field characteristics outside the air inlet duct of the test piece in the test section meet the flow field characteristic distribution law, the wind tunnel flow conditions of the test piece in the test section include: According to the preset initial intake flow rate and the pre-obtained initial wind tunnel flow condition of the intake duct, the wind tunnel simulation flow parameters are set, and the initial pressure curve of the lip area is collected based on the wind tunnel simulation flow parameters; According to the difference between the actual pressure curve and the target pressure curve, the air intake flow rate or the wind tunnel flow condition of the test piece to be tested in the test section is adjusted on the basis of the initial pressure curve until the difference between the actual pressure curve and the target pressure curve is less than a preset threshold; the parameters in the actual pressure curve are collected based on the adjusted air intake flow rate and the adjusted wind tunnel flow condition; When the difference between the actual pressure curve and the target pressure curve is less than a preset threshold, the wind tunnel inflow condition and the target air intake flow rate of the test piece in the test section are obtained; The icing range test is performed on the test piece according to the wind tunnel flow conditions, including: An icing range test is performed on the test piece according to the adjusted wind tunnel inflow condition and the target air intake flow rate.

2. The method according to claim 1, characterized in that When calculating that the flow field characteristics inside the air inlet duct and the flow field characteristics outside the air inlet duct of the test piece in the test section meet the flow field characteristic distribution law, the wind tunnel flow conditions of the test piece in the test section include: When the second ratio of the Mach number of the airflow inside the inlet duct of the test piece in the test section and the Mach number of the wind tunnel airflow is calculated to be the same as the first ratio, the wind tunnel inflow condition of the test piece in the test section; the wind tunnel inflow condition includes inflow wind speed, temperature and ambient pressure.

3. The method according to claim 1, characterized in that The flow field characteristics include the pressure of the flow field, and the flow field characteristics distribution law also includes a target pressure curve of the aircraft's air inlet lip area; the lip area refers to the portion of the aircraft's outer wall that diverts the far-field incoming flow to the end position; the end position corresponds to the position where the streamlines of different far-field incoming flows after diversion begin to be parallel.

4. The method according to claim 1, characterized in that: The icing range test is performed on the test piece according to the adjusted wind tunnel inflow piece and the target air intake flow rate, including: Obtaining water droplet correction impact parameters of the aircraft under test under natural flow conditions; With the goal of maintaining the water droplet modified impact parameter, the water droplet diameter is adjusted according to the wind tunnel incoming flow condition to obtain a target water droplet diameter; According to the adjusted wind tunnel inflow condition and the target water droplet diameter, an icing range test is performed on the test piece.

5. The method according to claim 1, characterized in that: Before performing the step of adjusting the initial air intake flow rate or the initial wind tunnel flow condition of the test piece in the test section based on the initial pressure curve, the method further includes: According to the preset initial intake air flow rate of the test piece in the test section, when a second ratio of the Mach number of the airflow inside the air inlet duct of the test piece in the test section to the Mach number of the airflow in the wind tunnel is calculated to be the same as the first ratio, the initial wind tunnel inflow condition of the test piece in the test section; Alternatively, based on the preset initial wind tunnel flow conditions of the specimen to be tested in the test section, the initial intake flow rate of the specimen to be tested in the test section is calculated when a second ratio of the Mach number of the airflow inside the inlet duct of the specimen to be tested in the test section to the Mach number of the wind tunnel airflow is the same as the first ratio.

6. An inlet icing range test device, characterized in that: The device comprises: The flow field characteristic acquisition module is used to obtain the flow field characteristic distribution law corresponding to the aircraft under test under natural flow conditions; A scaling module is used to reduce the aircraft to be tested according to a preset size ratio to obtain a test piece to be tested; the preset size ratio is determined according to the test section size and the blocking ratio requirement; A calculation module, used for calculating the wind tunnel flow conditions of the test piece to be tested in the test section when the flow field characteristics inside the air inlet duct and the flow field characteristics outside the air inlet duct of the test piece to be tested in the test section meet the flow field characteristics distribution law; the flow field characteristics inside the air inlet duct are determined by the intake simulation capability of the test section; A test module, used for performing an icing range test on the test piece to be tested according to the wind tunnel flow conditions; The flow field characteristic acquisition module comprises: The inflow acquisition submodule is used to obtain the far-field inflow conditions corresponding to the natural inflow conditions; the far-field inflow conditions include inflow wind speed, temperature and ambient pressure; A cross-section setting submodule, used for setting a calibration cross-section for measuring the flow field inside the air inlet of the aircraft to be tested according to a streamline turning point formed by the fluid entering the air inlet of the aircraft; A program calling submodule is used to call a preset program to simulate the impact of airflow on the aircraft to be tested according to the far-field incoming flow condition, and calculate the far-field airflow Mach number of the aircraft to be tested under the natural incoming flow condition; The program calling submodule is further used to call a preset program to simulate the impact of airflow on the aircraft to be tested according to the far-field incoming flow condition, and calculate the internal airflow Mach number of the aircraft to be tested under the natural incoming flow condition based on the calibrated cross section; The calculation submodule is used to calculate a first ratio of the far-field airflow Mach number to the internal airflow Mach number as the flow field characteristic distribution law.

7. A computing device, characterized in that The method comprises at least one processor and at least one memory connected to the processor; the memory stores program instructions for being executed by the processor, and the processor calls the program instructions to execute any method according to claims 1 to 6.

8. A computer storage medium storing computer instructions, characterized in that: The computer instructions enable the computer to execute the method according to any one of claims 1 to 6.

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