CN117191336B - Flexible epidermis drag reduction efficacy test evaluation method based on flat model - Google Patents
Flexible epidermis drag reduction efficacy test evaluation method based on flat model Download PDFInfo
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- 238000012360 testing method Methods 0.000 title claims abstract description 99
- 230000009467 reduction Effects 0.000 title claims abstract description 45
- 210000002615 epidermis Anatomy 0.000 title claims abstract description 30
- 238000011156 evaluation Methods 0.000 title claims abstract description 24
- 239000013068 control sample Substances 0.000 claims abstract description 63
- 239000000523 sample Substances 0.000 claims abstract description 52
- 238000004519 manufacturing process Methods 0.000 claims abstract description 20
- 238000013461 design Methods 0.000 claims description 42
- 239000000758 substrate Substances 0.000 claims description 39
- 210000003491 skin Anatomy 0.000 claims description 28
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 11
- 229910000838 Al alloy Inorganic materials 0.000 claims description 6
- 239000011248 coating agent Substances 0.000 claims description 6
- 238000000576 coating method Methods 0.000 claims description 6
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 4
- 239000000463 material Substances 0.000 claims description 4
- 239000000741 silica gel Substances 0.000 claims description 4
- 229910002027 silica gel Inorganic materials 0.000 claims description 4
- 230000000694 effects Effects 0.000 abstract description 10
- 238000005516 engineering process Methods 0.000 abstract description 8
- 238000012545 processing Methods 0.000 abstract description 6
- 238000005259 measurement Methods 0.000 description 8
- 230000007547 defect Effects 0.000 description 4
- 239000012530 fluid Substances 0.000 description 4
- 238000004364 calculation method Methods 0.000 description 3
- 239000013074 reference sample Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000002457 bidirectional effect Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
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Abstract
The invention relates to a flexible epidermis drag reduction efficacy test evaluation method based on a flat model, which comprises the following steps: manufacturing a test sample flat model S and measuring the actual thickness H S; manufacturing a control sample flat model D i with different thicknesses and measuring the actual thickness H i; measuring the resistance f S of the test sample plate model; measuring the resistance F i of each control plate model; calculating the theoretical resistance F S of the control plate model D S having a thickness equal to H S according to (formula 1); the drag reduction efficacy η S of the test-like plate model S was calculated according to (formula 2). The drag reduction effect of the flexible epidermis can be calculated and obtained by arranging five steps without grooving the surface of the flat model, the operation is simple, and the requirements on the processing technology are not high; meanwhile, the thickness parameters of the test sample and the control sample are brought into the evaluation range, so that the evaluation precision and the result accuracy can be effectively improved.
Description
Technical Field
The invention relates to the technical field of hydrodynamic tests, in particular to a flexible epidermis drag reduction efficacy test evaluation method based on a flat model.
Background
The total fluid resistance experienced by an aircraft during travel includes frictional resistance and viscous drag. The frictional resistance is due to the viscosity of fluid media such as air, water and the like, the aircraft drives the fluid near the surface to move along with the fluid, the tangential stress generated on the surface of the aircraft projects along the flowing direction, the magnitude of the tangential stress is mainly related to the navigational speed, the contact surface area and the surface state, and the tangential stress accounts for about 60% -80% of the total resistance; the viscous-pressure resistance is generated by the pressure difference between the head and the tail of the aircraft, namely, the resultant force of the pressure applied to the surface of the aircraft along the movement direction, the magnitude of the resultant force is mainly related to the line type of the aircraft, and the resultant force accounts for about 20% -40% of the total resistance. With the increasing maturity of the linear design of the aircraft, the space and the amplitude for reducing the viscous-pressure resistance are smaller and smaller, and the friction resistance which is up to 60% -80% is greatly reduced, so that the aircraft drag reduction device is an important break.
The flexible skin technology can delay transition from laminar flow to turbulent flow and reduce shear stress of turbulent wall surfaces by changing the surface state of the aircraft, so that great resistance reduction is realized, and the flexible skin technology is a hotspot for drag reduction research of the aircraft. Because the flexible skin drag reduction technology has strong correlation with turbulent boundary layer flow, bidirectional fluid-solid coupling, mechanical properties of materials and the like, the drag reduction effect of the flexible skin drag reduction technology is not yet effectively analyzed by theory and a numerical simulation method at present and is mainly evaluated by experiments. The flat model has the characteristics of high friction resistance ratio, easiness in processing and the like, and is the most commonly used test model for evaluating the drag reduction efficacy of the flexible skin.
In the prior art, when a flat model is used for carrying out drag reduction efficacy evaluation test of a flexible skin, a groove is formed on the surface of the flat model, and then the flexible skin is stuck in the groove to form a test sample flat model; and then setting a plurality of control sample flat plate models which have the same thickness as the test sample flat plate models and are not adhered with the flexible epidermis, and calculating the drag reduction effect of the flexible epidermis by measuring the resistance values of the test sample flat plate models and the control sample flat plate models. However, this method has the following disadvantages:
(1) The requirement on the size matching of the groove and the flexible skin is extremely high, and when the size of the flexible skin is smaller, gaps and concave platforms are easy to form around the flexible skin; when the size of the flexible epidermis is bigger, the flexible epidermis is easy to generate bulges and bosses; meanwhile, the flexible surface is easy to generate local deformation, and after the flexible surface is adhered to the bottom and the periphery of the groove, the flatness of the outer surface of the flexible surface is difficult to ensure;
The defects of gaps, steps, bulges, unevenness and the like can cause turbulence during an evaluation test, and the resistance measurement value is seriously influenced, so that the precision of the evaluation test is influenced;
(2) The thickness difference of the test sample flat plate model and the control sample flat plate model caused by processing errors is needed to be ignored, but the thickness parameter of the model has a larger influence on the resistance measurement value, and the measurement result accuracy is not high due to the fact that the thickness difference is ignored;
(3) Because the flexible epidermis is stuck in the recess, the area that flexible epidermis can cover on the flat model is than less to make effective measurement signal less, be unfavorable for accurately distinguishing the drag reduction efficiency of flexible epidermis.
Therefore, the conventional drag reduction efficacy evaluation test based on the flat model has the problems that the test sample model is difficult to manufacture, the manufacturing defects are large, the area occupation ratio of the flexible skin is small, the thickness difference between the test sample and the control sample flat plate cannot be considered, and the evaluation accuracy of the drag reduction efficacy of the flexible skin is greatly affected.
Disclosure of Invention
Aiming at the defects in the prior art, the inventor provides a flexible epidermis drag reduction efficacy test evaluation method based on a flat model, which has reasonable structure, and the drag reduction efficacy of the flexible epidermis can be calculated and obtained by arranging five steps without slotting on the surface of the flat model, so that the operation is simple, and the requirements on the processing technology are not high; meanwhile, the thickness parameters of the test sample and the control sample are brought into the evaluation range, so that the evaluation precision and the result accuracy can be effectively improved.
The technical scheme adopted by the invention is as follows:
a flexible epidermis drag reduction efficacy test evaluation method based on a flat model comprises the following steps:
S1, manufacturing a test sample flat plate model S with the design thickness of H A, and measuring the actual thickness H S of the test sample flat plate model S;
S2, manufacturing a control sample flat plate model D 1 with the design thickness of H A1, and measuring the actual thickness H 1 of the control sample flat plate model D 1;
Manufacturing a control plate model D 2 with the design thickness of H A2, and measuring the actual thickness H 2 of the control plate model D 2;
The design thickness H A1 of the control sample flat model D 1 is smaller than or equal to the design thickness H A of the test sample flat model S;
The design thickness H A2 of the control sample flat model D 2 is larger than the design thickness H A of the test sample flat model S;
S3, measuring the actual resistance f S of the test sample plate model S in the step S1 through a high-speed cavitation water drum test;
Measuring the control sample flat plate model D 1 and the control sample flat plate model D 2 obtained in the step S2 one by one through a high-speed cavitation water drum test, and corresponding actual resistance F 1 and actual resistance F 2;
S4, setting a control sample flat plate model D S, wherein the thickness of the control sample flat plate model D S is equal to the actual thickness H S of the test sample flat plate model S;
Calculating according to the formula 1 to obtain theoretical resistance F S of the control sample flat plate model D S with the thickness of H S;
In the formula 1, F S represents the theoretical resistance of the control plate model D S having a thickness of H S,
F 1 represents the actual resistance measured in step s3 of the control plate model D 1 having the actual thickness H 1,
F 2 represents the actual resistance measured in step s3 of the control plate model D 2 having the actual thickness H 2,
H S represents the thickness of the control plate model D S,
H 1 represents the actual thickness of the control plate model D 1,
H 2 represents the actual thickness of the control plate model D 2;
S5, calculating drag reduction efficacy eta S of the test sample flat plate model S according to the formula 2;
in (formula 2), η S represents the drag reduction efficacy of the test-like flat-plate model S,
F S represents the theoretical resistance of the control plate model D S with the thickness H S calculated in the step S4,
F S represents the actual resistance of the test-like flat model S measured experimentally in step S3.
As a further improvement of the above technical scheme:
The structure of the test sample flat plate model S is as follows: the flexible surface skin is uniformly adhered to the surface of the substrate, and the substrate is completely wrapped.
The base plate adopts the integral type structure, and the base plate is including the head that is oval form, be dull and stereotyped form main part, the afterbody that is wedge that links up in proper order.
The shape and material of the control plate model D 1, the control plate model D 2, and the control plate model D S are the same as those of the substrate.
The substrate is made of aluminum alloy.
The flexible surface skin is made of a flexible silica gel plate.
And measuring the actual thickness H S, the actual thickness H 1 and the actual thickness H 2 corresponding to the test sample flat plate model S, the control sample flat plate model D 1 and the control sample flat plate model D 2 by adopting a vernier caliper.
The beneficial effects of the invention are as follows:
the invention has compact and reasonable structure and convenient operation, and can accurately calculate the drag reduction effect of the flexible epidermis based on the linear fitting and data interpolation principle by arranging five steps, thereby effectively improving the accuracy of the drag reduction effect test evaluation method of the flexible epidermis and realizing the accurate test evaluation of the drag reduction effect of the flexible epidermis.
In the aspect of test model manufacturing, the method for forming the grooves on the surface of the substrate used in the traditional evaluation test is abandoned, and the defects of gaps, steps, bulges, unevenness and the like caused by mismatching of the sizes of the grooves and the flexible surface can be effectively prevented by adopting a mode of sticking a single flexible surface on the periphery of the substrate, so that turbulence is prevented during the evaluation test, the influence on the measurement result is avoided, and the precision of the evaluation test is effectively improved.
According to the invention, the flexible epidermis completely wraps the outer surface of the substrate, so that the actual coverage area of the flexible epidermis on the flat model is increased, and therefore, the effective measurement signal in a high-speed cavitation water drum test is effectively increased, and the drag reduction effect of the flexible epidermis is accurately distinguished.
According to the invention, the theoretical resistance corresponding to the reference sample flat plate model D S with the same actual thickness as the test sample flat plate model S is obtained through calculation (formula 1), so that the influence of neglecting the thickness difference between the test sample flat plate model and the reference sample flat plate model in the traditional evaluation test is eliminated, and the precision of the evaluation result can be greatly improved.
Drawings
FIG. 1 is a flow chart of the present invention.
FIG. 2 is a cross-sectional view of a test sample plate model S according to the present invention.
FIG. 3 is a second cross-sectional view of a test sample plate model S according to the present invention.
Wherein: 1. a substrate; 101. a header; 102. a main body portion; 103. and a tail part.
Detailed Description
The following describes specific embodiments of the present invention with reference to the drawings.
Embodiment one:
as shown in fig. 1-3, the method for evaluating the drag reduction efficacy test of the flexible epidermis based on the flat model of the present embodiment includes the following steps:
S1, manufacturing a test sample flat plate model S with the design thickness of H A, and measuring the actual thickness H S of the test sample flat plate model S;
S2, manufacturing a control sample flat plate model D 1 with the design thickness of H A1, and measuring the actual thickness H 1 of the control sample flat plate model D 1;
Manufacturing a control plate model D 2 with the design thickness of H A2, and measuring the actual thickness H 2 of the control plate model D 2;
The design thickness H A1 of the control sample flat model D 1 is smaller than or equal to the design thickness H A of the test sample flat model S;
The design thickness H A2 of the control plate model D 2 is greater than the design thickness H A of the test plate model S;
S3, measuring the actual resistance f S of the test sample plate model S in the step S1 through a high-speed cavitation water drum test;
Measuring the control sample flat plate model D 1 and the control sample flat plate model D 2 obtained in the step S2 one by one through a high-speed cavitation water drum test, and corresponding actual resistance F 1 and actual resistance F 2;
S4, setting a control sample flat plate model D S, wherein the thickness of the control sample flat plate model D S is equal to the actual thickness H S of the test sample flat plate model S;
Calculating according to the formula 1 to obtain theoretical resistance F S of the control sample flat plate model D S with the thickness of H S;
In the formula 1, F S represents the theoretical resistance of the control plate model D S having a thickness of H S,
F 1 represents the actual resistance measured in step s3 of the control plate model D 1 having the actual thickness H 1,
F 2 represents the actual resistance measured in step s3 of the control plate model D 2 having the actual thickness H 2,
H S represents the thickness of the control plate model D S,
H 1 represents the actual thickness of the control plate model D 1,
H 2 represents the actual thickness of the control plate model D 2;
S5, calculating drag reduction efficacy eta S of the test sample flat plate model S according to the formula 2;
in (formula 2), η S represents the drag reduction efficacy of the test-like flat-plate model S,
F S represents the theoretical resistance of the control plate model D S with the thickness H S calculated in the step S4,
F S represents the actual resistance of the test-like flat model S measured experimentally in step S3.
The structure of the test sample flat plate model S is: the flexible surface coating comprises a substrate 1 and a flexible surface coating, wherein the flexible surface coating is uniformly adhered to the surface of the substrate 1, and the substrate 1 is completely wrapped.
The substrate 1 adopts an integral structure, and the substrate 1 comprises an elliptical head part 101, a flat main body part 102 and a wedge-shaped tail part 103 which are sequentially connected.
The shape and material of the control plate model D 1, the control plate model D 2, and the control plate model D S are the same as those of the substrate 1.
The substrate 1 is made of aluminum alloy.
The flexible surface skin adopts a flexible silica gel plate.
And measuring the actual thickness H S, the actual thickness H 1 and the actual thickness H 2 corresponding to the test sample flat plate model S, the control sample flat plate model D 1 and the control sample flat plate model D 2 by adopting a vernier caliper.
The embodiment provides a method for evaluating a drag reduction effect test of a flexible epidermis based on a flat model, which is based on the principle that when the thickness of the flat model is slightly changed, the thickness value and the resistance value of the flat model are approximately in a linear relation, so that (formula 1) is obtained, and the theoretical resistance of a flat model D S without a flexible epidermis control sample under the same thickness is obtained through calculation according to (formula 1), so that the drag reduction effect of a flat model S with a flexible epidermis relative to a flat model D S without a flexible epidermis control sample can be obtained through calculation according to (formula 2).
Embodiment two:
The present embodiment is different from the first embodiment in that: in the embodiment, taking a substrate 1 with the dimensions of 800mm×200mm×14mm as an example, a test sample flat model S with a thickness of 2.27mm of flexible epidermis is covered on the substrate 1, and a control sample flat model D 3 is additionally added, where the corresponding design thickness H A3 is the same as the design thickness H A of the substrate 1;
Thus, the flexible epidermis drag reduction efficacy test evaluation method based on the flat model comprises the following steps:
S1, manufacturing a test sample flat plate model S with the design thickness of H A, and measuring the actual thickness H S of the test sample flat plate model S;
s1.1, the structure of the test sample flat plate model S is as follows: the flexible surface skin is uniformly adhered to the surface of the substrate 1, and the substrate 1 is completely wrapped;
s1.2, a substrate 1 adopts an integrated structure, and the substrate 1 comprises an elliptical head part 101, a flat main body part 102 and a wedge-shaped tail part 103 which are sequentially connected;
S1.3, when the flexible skin is adhered to the outer surface of the substrate 1, adhering a single flexible skin to the upper surface of the substrate 1, then bypassing the head 101, adhering to the lower surface of the substrate 1, and then cutting off the redundant part of the flexible skin, so that the flexible skin only leaves a seam at the tail 103 of the substrate 1;
s1.4, the substrate 1 made of aluminum alloy adopted in the embodiment has the dimensions of 800mm multiplied by 200mm multiplied by 14mm (length L multiplied by width W multiplied by thickness H), the ratio of the short axis of the head part to the long axis is 1:5, and the ratio of the short axis of the tail part to the long axis is 1:5;
The flexible surface skin is made of a flexible silica gel plate, the thickness of the flexible surface skin is 2.27mm, the density of the flexible surface skin is 1105.6Kg/m < 3 >, the Shore hardness A is 33.1 degrees, the elastic modulus is 0.4MPa, and the Poisson ratio is 0.24;
s1.5, measuring the actual thickness H S of the test sample flat plate model S by adopting a vernier caliper;
As can be seen from step S1.4, the design thickness H A of the test-sample flat-plate model S is 18.54mm, and the actual thickness H S measured using a cursor is 18.64mm;
S2, manufacturing a control sample flat plate model D 1 with the design thickness of H A1, and measuring the actual thickness H 1 of the control sample flat plate model D 1;
Manufacturing a control plate model D 2 with the design thickness of H A2, and measuring the actual thickness H 2 of the control plate model D 2;
Manufacturing a control plate model D 3 with the design thickness of H A3, and measuring the actual thickness H 3 of the control plate model D 3;
Design thickness H A1 of control plate model D 1 is equal to design thickness H A of test plate model S;
The design thickness H A2 of the control plate model D 2 is greater than the design thickness H A of the test plate model S;
The design thickness H A3 of the control plate model D 3 is smaller than the design thickness H A of the test plate model S;
s2.1, as known from the step S1.4, the design thickness H A of the test sample flat plate model S is 18.54mm, and the design thickness H A1, the design thickness H A2 and the design thickness H A3 corresponding to the control sample flat plate model D 1, the control sample flat plate model D 2 and the control sample flat plate model D 3 are 18.54mm, 22.00mm and 14.00mm respectively;
The design thickness H A3 corresponding to the control plate model D 3 is the same as the design thickness of the substrate 1;
S2.2, the control plate model D 1, the control plate model D 2 and the control plate model D 3 are plates with the same shape as the substrate 1, and in the embodiment, the plates are made of aluminum alloy;
s2.3, manufacturing a control sample flat plate model D 3 by adopting the same processing technology as that of the substrate 1 in the step S1.3;
For the control sample flat plate model D 1 and the control sample flat plate model D 2, the design thickness of the control sample flat plate model D is larger than the thickness of the substrate 1 in the step S1.3, and the control sample flat plate model D are manufactured by adopting a linear expansion processing technology;
Thereby manufacturing three control sample flat plate models D 1, D 2 and D 3 with different thicknesses;
S2.4, measuring the actual thickness H 1, the actual thickness H 2 and the actual thickness H 3 corresponding to the control sample flat plate model D 1, the control sample flat plate model D 2 and the control sample flat plate model D 3 by adopting a vernier caliper, wherein the values of the actual thickness H 1, the actual thickness H 2 and the actual thickness H 3 are 18.33mm, 22.15mm and 14.03mm respectively in the embodiment;
S3, measuring the actual resistance f S of the test sample plate model S obtained in the step S1 through a high-speed cavitation water drum test;
Measuring the control sample flat plate model D 1, the control sample flat plate model D 2 and the control sample flat plate model D 3 obtained in the step S2 one by one through a high-speed cavitation water drum test, wherein the corresponding actual resistance F 1, the actual resistance F 2 and the actual resistance F 3 are obtained;
s3.1, in the resistance measurement process, the attitude angles such as attack angle, drift angle and the like of the flat model are required to be kept to be 0;
s3.2, the test water speeds are respectively set to be 2m/s, 3m/s, 4m/s, 6m/s, 8m/s, 10m/s and 12m/s;
s3.3. in this example, the measured resistance data at different test water speeds are shown in table 1,
Table 1 resistance measurement data for each plate model
S4, setting a control sample flat plate model D S, wherein the thickness of the control sample flat plate model D S is equal to the actual thickness H S of the test sample flat plate model S;
Calculating according to the formula 1 to obtain theoretical resistance F S of the control sample flat plate model D S with the thickness of H S;
In the formula 1, F S represents the theoretical resistance of the control plate model D S having a thickness of H S,
F 1 represents the actual resistance measured in step s3 of the control plate model D 1 having the actual thickness H 1,
F 2 represents the actual resistance measured in step s3 of the control plate model D 2 having the actual thickness H 2,
H S represents the thickness of the control plate model D S, in this example H s =18.64 mm,
H 1 represents the actual thickness of the control plate model D 1, in this example H 1 =18.33 mm,
H 2 represents the actual thickness of the control plate model D 2; h 2 =22.15 mm in this example;
s4.1, the control sample flat plate model D S is a plate with the shape consistent with that of the substrate 1, and in the embodiment, the plate is made of aluminum alloy;
S4.2 in the present example, theoretical resistance F S of a control plate model D S with a thickness of H S at different test water speeds was calculated according to (1), the results of which are shown in Table 2,
TABLE 2 theoretical resistance F of control plate model D S with thickness H S S
| Test Water speed U (m/S) | 2 | 3 | 4 | 6 | 8 | 10 | 12 |
| Theoretical resistance F S (N) | 5.27 | 10.99 | 18.27 | 38.47 | 66.19 | 101.44 | 144.21 |
S5, calculating drag reduction efficacy eta S of the test sample flat plate model S according to the formula 2;
in (formula 2), η S represents the drag reduction efficacy of the test-like flat-plate model S,
F S represents the theoretical resistance of the control plate model D S with the thickness H S calculated in the step S4,
F S represents the actual resistance of the test sample flat model S measured in the test in step S3;
S5.1 in the present example, the drag reduction effect η S of the test sample plate model S at different test water speeds calculated according to (formula 2) is shown in Table 3.
TABLE 3 results of Flexible epidermis drag reduction efficacy plate test
| Test water speed U (m/s) | 2 | 3 | 4 | 6 | 8 | 10 | 12 |
| Drag reduction efficacy eta | 13.5％ | 2.6％ | 0.5％ | -1.3％ | -1.9％ | -4.0％ | -4.5％ |
The above description is intended to illustrate the invention and not to limit it, the scope of which is defined by the claims, and any modifications can be made within the scope of the invention.
Claims (5)
1. A flexible epidermis drag reduction efficacy test evaluation method based on a flat model is characterized in that: the method comprises the following steps:
S1, manufacturing a test sample flat plate model S with the design thickness of H A, and measuring the actual thickness H S of the test sample flat plate model S;
The structure of the test sample flat plate model S is as follows: the flexible surface coating comprises a substrate (1) and a flexible surface coating, wherein the flexible surface coating is uniformly adhered to the surface of the substrate (1) and completely wraps the substrate (1);
the substrate (1) adopts an integrated structure, and the substrate (1) comprises an elliptical head part (101), a flat main body part (102) and a wedge-shaped tail part (103) which are sequentially connected;
S2, manufacturing a control sample flat plate model D 1 with the design thickness of H A1, and measuring the actual thickness H 1 of the control sample flat plate model D 1;
Manufacturing a control plate model D 2 with the design thickness of H A2, and measuring the actual thickness H 2 of the control plate model D 2;
The design thickness H A1 of the control sample flat model D 1 is smaller than or equal to the design thickness H A of the test sample flat model S;
The design thickness H A2 of the control sample flat model D 2 is larger than the design thickness H A of the test sample flat model S;
S3, measuring the actual resistance f S of the test sample plate model S in the step S1 through a high-speed cavitation water drum test;
Measuring the control sample flat plate model D 1 and the control sample flat plate model D 2 obtained in the step S2 one by one through a high-speed cavitation water drum test, and corresponding actual resistance F 1 and actual resistance F 2;
S4, setting a control sample flat plate model D S, wherein the thickness of the control sample flat plate model D S is equal to the actual thickness H S of the test sample flat plate model S;
Calculating according to the formula 1 to obtain theoretical resistance F S of the control sample flat plate model D S with the thickness of H S;
In the formula 1, F S represents the theoretical resistance of the control plate model D S having a thickness of H S,
F 1 represents the actual resistance measured in step s3 of the control plate model D 1 having the actual thickness H 1,
F 2 represents the actual resistance measured in step s3 of the control plate model D 2 having the actual thickness H 2,
H S represents the thickness of the control plate model D S,
H 1 represents the actual thickness of the control plate model D 1,
H 2 represents the actual thickness of the control plate model D 2;
S5, calculating drag reduction efficacy eta S of the test sample flat plate model S according to the formula 2;
in (formula 2), η S represents the drag reduction efficacy of the test-like flat-plate model S,
F S represents the theoretical resistance of the control plate model D S with the thickness H S calculated in the step S4,
F S represents the actual resistance of the test-like flat model S measured experimentally in step S3.
2. The flexible skin drag reduction efficacy test assessment method based on a flat panel model as set forth in claim 1, wherein: the shape and material of the control plate model D 1, the control plate model D 2, and the control plate model D S are the same as those of the substrate (1).
3. The flexible skin drag reduction efficacy test assessment method based on a flat panel model as set forth in claim 1, wherein: the substrate (1) is made of aluminum alloy.
4. The flexible skin drag reduction efficacy test assessment method based on a flat panel model as set forth in claim 1, wherein: the flexible surface skin is made of a flexible silica gel plate.
5. The flexible skin drag reduction efficacy test assessment method based on a flat panel model as set forth in claim 1, wherein: and measuring the actual thickness H S, the actual thickness H 1 and the actual thickness H 2 corresponding to the test sample flat plate model S, the control sample flat plate model D 1 and the control sample flat plate model D 2 by adopting a vernier caliper.
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