Semiconductor friction force balance and method of using same

Abstract

The application belongs to the technical field of hypersonic wind tunnel test, and discloses a semiconductor friction resistance balance and a use method thereof. The fixed frame of the measuring assembly is a square block, and the floating frame is a U-shaped block. The fixed frame is fixed on the base, two vertical elastic strain beams I are fixed on the left side of the fixed frame, and the free ends of the two elastic strain beams I are respectively fixed on the right side of the two vertical columns of the floating frame. The central cavity of the U-shaped block is fixed with two elastic strain beams II which are parallel to the left side of the fixed frame. The top end of the elastic strain beam II is fixed with a barrier disc, and the top surface of the barrier disc is fixed with a floating element. The outer shell is covered on the base, the floating element is located in the circular hole on the upper surface of the outer shell, and there is an annular gap between the circular hole and the floating element. The use method includes an installation method, a wiring method, a design and processing test method and a self-weight influence data processing method. The balance and the use method thereof improve the measurement sensitivity, reduce or even eliminate the temperature effect, and realize the accurate measurement of the micro friction resistance.

Description

Technical Field

[0001] This invention belongs to the field of hypersonic wind tunnel testing technology, specifically relating to a semiconductor friction resistance balance and its usage method. Background Technology

[0002] Accurate measurement of surface friction drag is of great significance for predicting the aerodynamic performance of hypersonic vehicles, evaluating the thrust characteristics of scramjet engines, and determining the technical and tactical indicators of hypersonic weapons. Surface friction drag is significant for hypersonic vehicles, accounting for up to 50% of the total drag, but obtaining accurate and reliable measurement data is extremely difficult. Currently, the direct measurement method is commonly used. This method is based on the balance of surface friction forces, where a floating element is directly mounted flush with the surface to be measured, where the contact tangential force is applied. The local friction drag is obtained by measuring the displacement of the floating element under stress and its corresponding relationship.

[0003] There are many challenges in measuring surface friction resistance under hypersonic conditions: the absolute value of friction resistance on small-area measuring elements is small, requiring high sensitivity of the measuring device; under hypersonic incoming flow conditions, there is a normal load on the surface of the aircraft that is much greater than the friction resistance; there is a large impact load during the establishment of the hypersonic wind tunnel flow field, requiring the measuring device to have high structural stiffness and strength; the wind tunnel test aircraft model has a complex aerodynamic shape and a large size scale, requiring the measuring device to be small in size, etc.

[0004] Currently, the main problems with friction resistance balances are: strain gauge friction resistance balances generally use resistance strain gauges for output, resulting in low measurement sensitivity and a large measurement device size; piezoelectric friction resistance balances have rapid charge decay, which cannot meet the requirements for long-term continuous measurement.

[0005] Currently, there is an urgent need to develop a new type of semiconductor friction resistance balance and its application method. Summary of the Invention

[0006] One technical problem to be solved by the present invention is to provide a semiconductor friction resistance balance, and another technical problem to be solved by the present invention is to provide a method of using a semiconductor friction resistance balance.

[0007] The semiconductor friction resistance balance of the present invention is characterized in that the semiconductor friction resistance balance is made of F141 and includes a measuring component, a housing and a base; the measuring component includes a fixed frame, a floating frame, a floating element, an elastic strain beam I, a temperature self-compensating semiconductor strain gauge and a barrier disk; The fixed frame is a cube, and the floating frame is a U-shaped block. The bottom surface of the fixed frame is fixed to the base. Two elastic strain beams I, perpendicular to the left side of the fixed frame, are fixed to the left side of the fixed frame. The suspended ends of the two elastic strain beams I are fixed to the right side of the two columns of the floating frame, respectively. Two elastic strain beams II, parallel to the left side of the fixed frame, are fixed to the central cavity of the U-shaped block. The top of the elastic strain beams II is fixed to the bottom surface of the barrier plate, and a disc-shaped floating element is fixed to the top surface of the barrier plate. The housing covers the base, and the cavity inside the housing accommodates the measuring component. The floating element of the measuring component is located in a circular hole on the upper surface of the housing, and there is an annular gap between the circular hole and the floating element. There is a gap between the baffle plate and the inner wall of the housing. The annular gap and the gap form a labyrinth to prevent the airflow flowing through the surface of the housing from entering the cavity inside the housing and affecting the measuring component. Elastic strain beam I is a wedge-shaped strain beam, and the wedges of the two elastic strain beams I are in opposite directions; elastic strain beam II is a flat plate strain beam; temperature self-compensating semiconductor strain gauges are attached to both sides of elastic strain beam I and elastic strain beam II respectively; elastic strain beam I and elastic strain beam II decompose the surface friction resistance of the floating element into two mutually perpendicular longitudinal components and transverse components.

[0008] Furthermore, the temperature self-compensating semiconductor strain gauge is equipped with a temperature compensation resistor and a zero-point compensation resistor. After compensation, the temperature and zero-point drift of the semiconductor friction resistance balance do not exceed 1mV. The sensitivity coefficient range of the temperature self-compensating semiconductor strain gauge is 140±5.

[0009] Furthermore, the barrier disk is replaced by a barrier disk group, which includes several parallel barrier disks.

[0010] Furthermore, the support mechanism adopts an insert-type angle-of-attack mechanism; during the wind tunnel test, before the flow field is established, the test model is kept outside the flow field. After the flow field stabilizes, the insert-type angle-of-attack mechanism drives the test model into the flow field. Subsequently, the angle of attack, sideslip angle and roll angle of the test model are changed stepwise or continuously through the insert-type angle-of-attack mechanism.

[0011] The method of using the semiconductor friction resistance balance of the present invention includes an installation method, a wiring method, a design, processing and testing method, and a method for processing data on the influence of self-weight. S10. Installation method; According to the measurement positions required by the test, grooves are set at the corresponding positions of the test model, and the semiconductor friction resistance balance is fixed in the grooves. After fixing, the upper surface of the shell and the surface of the test model are smoothly transitioned. The hypersonic wind tunnel consists of a nozzle, a test section, and a diffuser connected sequentially from front to back. The test model is mounted on the support mechanism of the hypersonic wind tunnel test section via struts. The test model changes its angle of attack, sideslip angle, and roll angle through the support mechanism. S20. Wiring method; The differential electrical signal output by the semiconductor friction resistance balance enters the signal conditioning circuit of the hypersonic wind tunnel, and then enters the data acquisition computer through the data acquisition system. The data acquisition computer uses the balance formula to process the data and obtain the friction resistance acting on the surface of the floating element. The signal conditioning circuit is equipped with a dedicated regulated power supply and a control computer; the regulated power supply powers the signal conditioning circuit; the control computer is used to configure the parameters of the signal conditioning circuit. S30. Design of processing test methods; S31. Determine the response frequency and range of the semiconductor friction resistance balance according to the test requirements; S32. Finite element analysis of the modes and force conditions of a semiconductor triboelectric balance; S33. Optimize the structure of the semiconductor friction resistance balance; S34. Perform semiconductor triboelectric balance fabrication and mounting; S35. Perform static calibration of the semiconductor friction resistance balance to obtain the balance formula of the semiconductor friction resistance balance, and determine the main coefficient and cross-interference coefficient of the balance formula; S36. Conduct wind tunnel tests and obtain aerodynamic loads using a semiconductor friction resistance balance; S37. Perform data processing, calculate the dynamic pressure value through wind tunnel flow field parameters, and use the dynamic pressure value to make the aerodynamic load dimensionless to obtain the friction drag coefficients of the longitudinal and transverse components; perform vector synthesis to obtain the magnitude and direction of the friction drag. S50. Method for processing data on the influence of self-weight; During the movement of the experimental model, the angle between the experimental model and the direction of gravity of the semiconductor friction resistance balance and the axis of the semiconductor friction resistance balance changes continuously, affecting the differential electrical signal output by the semiconductor friction resistance balance, resulting in measurement errors caused by its own weight; the data processing method for the influence of self-weight is as follows: S61. In the absence of wind, the support mechanism of the hypersonic wind tunnel test section is operated, and the angle of attack, sideslip angle and roll angle of the test model are changed stepwise or continuously through the support mechanism; at the same time, the load of the semiconductor friction resistance balance during the movement is obtained, and the change in the attitude angle of the test model on the reading of the semiconductor friction resistance balance is obtained. S62. In the blowing state, the support mechanism of the hypersonic wind tunnel test section is operated. The angle of attack, sideslip angle and roll angle of the test model are changed stepwise or continuously through the support mechanism in the same way as in S61, so as to obtain the load of the semiconductor friction resistance balance in the blowing state. S63. Match the load obtained in S62 under the blowing state with the load obtained in S61 under the non-blowing state, add the corresponding self-weight correction amount, and then substitute it into the balance formula to calculate the load with self-weight influence. S64. Repeat S37 and S38 to obtain the magnitude and direction of the frictional resistance.

[0012] Furthermore, the finite element analysis includes frequency response analysis and static analysis of the semiconductor friction resistance balance; Frequency response analysis is used to obtain modal frequencies, aiming to determine the vibration frequencies and mode shapes of the semiconductor friction resistance balance to assess whether it meets wind tunnel testing requirements. In hypersonic shock tunnels, the low-frequency modal frequencies of the semiconductor friction resistance balance structure are specifically targeted. f > 2 / t , t The effective test time of the wind tunnel is the time when the effective test time of the hypersonic shock wind tunnel is... t At 10ms, the lowest frequency of the semiconductor friction resistance balance is greater than 200 Hz; Static analysis is used to calculate the response of a semiconductor friction balance structure under a fixed load. It is a key step in evaluating the sensitivity, linearity, and anti-interference capability of a semiconductor friction balance. Static analysis considers three types of loads: the first is frictional resistance, which is a shear force acting on the floating element parallel to the airflow direction; the second is airflow pressure, which is a pressure load perpendicular to the surface of the floating element; and the last is a torque load caused by uneven pressure distribution perpendicular to the surface of the floating element.

[0013] Furthermore, during the static calibration process, the semiconductor friction resistance balance is horizontally fixed and installed. Weights are suspended by a thin thread fixed to a special calibration loading head to load the semiconductor friction resistance balance, thereby reducing the influence of pulley friction error and horizontal line error caused by conventional balance calibration methods.

[0014] The measuring component of the semiconductor friction resistance balance of this invention is located inside the test model, and the floating element surface smoothly transitions to the test model surface without interfering with the flow field. The semiconductor friction resistance balance is a longitudinal and transverse dual-component balance, capable of simultaneously measuring the magnitude and direction of friction resistance. The balance employs a temperature-self-compensating semiconductor strain gauge for temperature compensation, eliminating the need for complex thermal protection and temperature correction. The temperature-self-compensating semiconductor strain gauge can pick up minute strains on the sensitive beam, reducing the surface area of ​​the floating element and mitigating the influence of pressure gradients on friction resistance measurement. It offers high measurement resolution and fast response speed, enabling millisecond-level measurements in pulsed shock wave wind tunnels.

[0015] In summary, the semiconductor friction resistance balance of this invention is small in size, highly sensitive, and has temperature compensation capabilities, reducing or even eliminating temperature effects. It can simultaneously measure the magnitude and direction of friction resistance, achieving precise measurement of minute amounts of friction resistance. The usage method is comprehensive, covering the entire process of using the semiconductor friction resistance balance, and has practical engineering value. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the semiconductor friction resistance balance of the present invention; Figure 2 This is a schematic diagram of the measuring components of the semiconductor friction resistance balance of the present invention; Figure 3 This is a schematic diagram of the installation of the semiconductor friction resistance balance of the present invention; Figure 4 This is the wiring diagram of the semiconductor friction resistance balance of the present invention; Figure 5 This is a flowchart illustrating the design, fabrication, and testing method of the semiconductor friction resistance balance of the present invention. Figure 6 This is a flowchart of the data processing method for the self-weight influence of the semiconductor triboelectric balance of the present invention. Figure 7 This is a schematic diagram of the temperature self-compensating semiconductor strain gauge in the semiconductor friction resistance balance of the present invention.

[0017] In the figure, 1. Fixed frame; 2. Floating frame; 3. Floating element; 4. Elastic strain beam I; 5. Temperature self-compensating semiconductor strain gauge; 6. Housing; 7. Base; 8. Barrier disk; 9. Nozzle; 10. Test section; 11. Test model; 12. Semiconductor friction resistance balance; 13. Support rod; 14. Diffuser; 15. Elastic strain beam II. Detailed Implementation

[0018] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0019] like Figure 1 , Figure 2 As shown, the semiconductor friction resistance balance of the present invention is made of F141 and includes a measuring component, a housing 6 and a base 7; the measuring component includes a fixed frame 1, a floating frame 2, a floating element 3, an elastic strain beam I 4, a temperature self-compensating semiconductor strain gauge 5 and a barrier disk 8; The fixed frame 1 is a cube, and the floating frame 2 is a U-shaped block. The bottom surface of the fixed frame 1 is fixed to the base 7. Two elastic strain beams I4 perpendicular to the left side of the fixed frame 1 are fixed to the left side of the fixed frame 1. The suspended ends of the two elastic strain beams I4 are fixed to the right side of the two columns of the floating frame 2 respectively. Two elastic strain beams II parallel to the left side of the fixed frame 1 are fixed to the central cavity of the U-shaped block. The top of the elastic strain beams II is fixed to the bottom surface of the barrier plate 8. A disc-shaped floating element 3 is fixed to the top surface of the barrier plate 8. The outer shell 6 covers the base 7. The cavity inside the outer shell 6 accommodates the measuring component. The floating element 3 of the measuring component is located in the circular hole on the upper surface of the outer shell 6. There is an annular gap between the circular hole and the floating element 3. There is a gap between the barrier disk 8 and the inner wall of the outer shell 6. The annular gap and the gap form a labyrinth to prevent the airflow flowing through the surface of the outer shell 6 from entering the cavity inside the outer shell 6 and affecting the measuring component. Elastic strain beam I4 is a wedge-shaped strain beam, and the wedges of the two elastic strain beams I4 are in opposite directions; elastic strain beam II is a flat plate strain beam; temperature self-compensating semiconductor strain gauges 5 are attached to both sides of elastic strain beam I4 and elastic strain beam II respectively; elastic strain beam I4 and elastic strain beam II decompose the surface friction resistance of the floating element 3 into two mutually perpendicular longitudinal components and transverse components.

[0020] Furthermore, the temperature self-compensating semiconductor strain gauge 5 is equipped with a temperature compensation resistor and a zero-point compensation resistor. After compensation, the temperature and zero-point drift of the semiconductor friction resistance balance 12 do not exceed 1mV. The sensitivity coefficient range of the temperature self-compensating semiconductor strain gauge 5 is 140±5.

[0021] Furthermore, the barrier disk 8 is replaced by a barrier disk group, which includes several parallel barrier disks 8.

[0022] Furthermore, the support mechanism adopts an insert-type angle-of-attack mechanism; during the wind tunnel test, before the flow field is established, the test model 11 is kept outside the flow field. After the flow field stabilizes, the insert-type angle-of-attack mechanism drives the test model 11 into the flow field. Subsequently, the angle of attack, sideslip angle and roll angle of the test model 11 are changed stepwise or continuously through the insert-type angle-of-attack mechanism.

[0023] The method of using the semiconductor friction resistance balance of the present invention includes an installation method, a wiring method, a design, processing and testing method, and a method for processing data on the influence of self-weight. S10. Installation method; According to the measurement position required by the test, a groove is set at the corresponding position of the test model 11, and the semiconductor friction resistance balance 12 is fixed in the groove. After fixing, the upper surface of the outer shell 6 and the surface of the test model 11 are smoothly transitioned. like Figure 3 As shown, the hypersonic wind tunnel includes a nozzle 9, a test section 10, and a diffuser connected sequentially from front to back; the test model 11 is mounted on the support mechanism of the hypersonic wind tunnel test section 10 via a support rod 13, and the test model 11 changes its angle of attack, sideslip angle, and roll angle through the support mechanism. S20. Wiring method; The differential electrical signal output by the semiconductor friction resistance balance 12 enters the signal conditioning circuit of the hypersonic wind tunnel, and then enters the data acquisition computer through the data acquisition system. The data acquisition computer uses the balance formula to process the data and obtain the friction resistance acting on the surface of the floating element 3. like Figure 4 As shown, the signal conditioning circuit is equipped with a dedicated regulated power supply and a control computer; the regulated power supply is used to power the signal conditioning circuit; the control computer is used to configure the parameters of the signal conditioning circuit. S30. Design and processing test methods are as follows: Figure 5 ; S31. Determine the response frequency and range of the semiconductor friction resistance balance 12 according to the test requirements; S32. Finite element analysis of the 12 modes and force conditions of a semiconductor friction resistance balance; S33. Optimize the structure of semiconductor friction resistance balance 12; S34. Perform the processing and mounting of the semiconductor friction resistance balance 12; S35. Perform static calibration of semiconductor friction resistance balance 12, obtain the balance formula of semiconductor friction resistance balance 12, and determine the main coefficient and cross-interference coefficient of the balance formula; S36. Conduct wind tunnel tests and obtain aerodynamic loads using semiconductor friction resistance balance 12; S37. Perform data processing, calculate the dynamic pressure value through wind tunnel flow field parameters, and use the dynamic pressure value to make the aerodynamic load dimensionless to obtain the friction drag coefficients of the longitudinal and transverse components; perform vector synthesis to obtain the magnitude and direction of the friction drag. S50. Method for processing data on the influence of self-weight; During the movement of the experimental model 11, the angle between the direction of gravity of the experimental model 11 and the semiconductor friction resistance balance 12 and the axis of the semiconductor friction resistance balance 12 changes continuously, affecting the differential electrical signal output by the semiconductor friction resistance balance 12, resulting in measurement errors caused by its own weight; such as Figure 6 As shown, the data processing method for the influence of self-weight is as follows: S61. In the absence of wind, the support mechanism of the hypersonic wind tunnel test section 10 is operated, and the angle of attack, sideslip angle and roll angle of the test model 11 are changed stepwise or continuously through the support mechanism; at the same time, the load of the semiconductor friction resistance balance 12 during the movement is obtained, and the change in the attitude angle of the test model 11 on the reading of the semiconductor friction resistance balance 12 is obtained. S62. In the blowing state, the support mechanism of the hypersonic wind tunnel test section 10 is operated. The angle of attack, sideslip angle and roll angle of the test model 11 are changed stepwise or continuously through the support mechanism in the same way as in S61, so as to obtain the load of the semiconductor friction resistance balance 12 in the blowing state. S63. Match the load obtained in S62 under the blowing state with the load obtained in S61 under the non-blowing state, add the corresponding self-weight correction amount, and then substitute it into the balance formula to calculate the load with self-weight influence. S64. Repeat S37 and S38 to obtain the magnitude and direction of the frictional resistance.

[0024] Furthermore, the finite element analysis includes frequency response analysis and static analysis of the semiconductor friction resistance balance 12; Frequency response analysis is used to obtain modal characteristics, specifically the vibration frequencies and mode shapes of the semiconductor friction resistance balance 12, to determine whether it meets the requirements for wind tunnel testing. In a hypersonic shock tunnel, the low-frequency modal frequencies of the semiconductor friction resistance balance 12 structure are required to be... f > 2 / t , t The effective test time of the wind tunnel is the time when the effective test time of the hypersonic shock wind tunnel is... t At 10ms, the lowest frequency of the semiconductor friction resistance balance 12 is greater than 200 Hz; Static analysis is used to calculate the response of the semiconductor friction resistance balance 12 structure under a fixed load. It is a key step in evaluating the sensitivity, linearity, and anti-interference capability of the semiconductor friction resistance balance 12. The static analysis considers three types of loads: the first is friction resistance, which is the shear force acting on the floating element 3 parallel to the airflow direction; the second is airflow pressure, which is the pressure load perpendicular to the surface of the floating element 3; and the last is the torque load caused by the uneven pressure distribution perpendicular to the surface of the floating element 3.

[0025] Furthermore, during the static calibration process, the semiconductor friction resistance balance 12 is horizontally fixed and installed. Weights are suspended by a thin thread fixed to a special calibration loading head to load the semiconductor friction resistance balance 12, thereby reducing the influence of pulley friction error and horizontal line error caused by conventional balance calibration methods.

[0026] Example 1:

[0027] like Figure 7 As shown, in this embodiment, Vs+1, Vs+2, Vs-, V+, and V- are the terminals of the temperature self-compensating semiconductor strain gauge 5. R0 is the temperature compensation resistor, R01 and R02 are the zero-point compensation resistors, and R1, R2, R3, and R4 are the strain-sensitive resistors. After compensation, the balance temperature and zero-point drift do not exceed 1mV.

[0028] The general specifications for strain gauge leads are as follows: the power input V+ lead is red, the V- lead is blue, the signal output Vs+1 and Vs+2 leads are yellow, and the Vs- lead is black. The leads from the strain gauge to the terminals should use the same insulated cable. The strain gauge number should be marked on the end of each lead. The measurement bridge wiring should be routed correctly (as straight as possible, horizontally and vertically), and free of cold solder joints.

[0029] The semiconductor friction resistance balance and its usage method described in this article are only one embodiment. In fact, there are many balance structures and usage methods that can achieve the functions of the semiconductor friction resistance balance and its usage method in this invention. Any simple modifications, alterations, and equivalent structural changes made to the above embodiments based on the technical essence of this invention shall still fall within the protection scope of this invention.

Claims

1. A semiconductor triboelectric balance, characterized in that, The semiconductor friction resistance balance (12) is made of F141 and includes a measuring component, a housing (6) and a base (7); the measuring component includes a fixed frame (1), a floating frame (2), a floating element (3), an elastic strain beam I (4), a temperature self-compensating semiconductor strain gauge (5) and a barrier disk (8); The fixed frame (1) is a cube, and the floating frame (2) is a U-shaped block. The bottom surface of the fixed frame (1) is fixed on the base (7). Two elastic strain beams I (4) perpendicular to the left side of the fixed frame (1) are fixed on the left side of the fixed frame (1). The suspended ends of the two elastic strain beams I (4) are fixed on the right side of the two columns of the floating frame (2). Two elastic strain beams II (15) parallel to the left side of the fixed frame (1) are fixed in the central cavity of the U-shaped block. The top of the elastic strain beams II (15) is fixed on the bottom surface of the barrier plate (8). The top surface of the barrier plate (8) is fixed with a disc-shaped floating element (3). The outer shell (6) covers the base (7). The cavity inside the outer shell (6) accommodates the measuring component. The floating element (3) of the measuring component is located in the circular hole on the upper surface of the outer shell (6). There is an annular gap between the circular hole and the floating element (3). There is a gap between the barrier disk (8) and the inner wall of the outer shell (6). The annular gap and the gap form a labyrinth to prevent the airflow flowing through the surface of the outer shell (6) from entering the cavity inside the outer shell (6) and affecting the measuring component. Elastic strain beam I (4) is a wedge-shaped strain beam, and the wedges of the two elastic strain beams I (4) are opposite in direction; elastic strain beam II (15) is a flat plate strain beam; temperature self-compensating semiconductor strain gauges (5) are attached to both sides of elastic strain beam I (4) and elastic strain beam II (15); elastic strain beam I (4) and elastic strain beam II (15) decompose the surface friction resistance of the floating element (3) into two mutually perpendicular longitudinal components and transverse components.

2. The semiconductor triboelectric balance according to claim 1, characterized in that, The temperature self-compensating semiconductor strain gauge (5) is equipped with a temperature compensation resistor and a zero-point compensation resistor. After compensation, the temperature and zero-point drift of the semiconductor friction resistance balance (12) do not exceed 1mV. The sensitivity coefficient of the temperature self-compensating semiconductor strain gauge (5) is in the range of 140±5.

3. The semiconductor triboelectric balance according to claim 1, characterized in that, The aforementioned barrier disk (8) is replaced by a barrier disk group, which includes several parallel barrier disks (8).

4. A method of using a semiconductor friction resistance balance, which is used in any one of the semiconductor friction resistance balances described in claims 1 to 3, characterized in that, This includes installation methods, wiring methods, design, processing, and testing methods, as well as methods for processing data on the impact of self-weight. S10. Installation method; According to the measurement position required by the test, a groove is set at the corresponding position of the test model (11), and the semiconductor friction resistance balance (12) is fixed in the groove. After fixing, the upper surface of the shell (6) and the surface of the test model (11) are smoothly transitioned. The hypersonic wind tunnel includes a nozzle (9), a test section (10), and a diffuser (14) connected sequentially from front to back. The test model (11) is mounted on the support mechanism of the test section (10) of the hypersonic wind tunnel via a strut (13). The test model (11) changes its angle of attack, sideslip angle, and roll angle through the support mechanism. S20. Wiring method; The differential electrical signal output by the semiconductor friction resistance balance (12) enters the signal conditioning circuit of the hypersonic wind tunnel, and enters the data acquisition computer through the data acquisition system. The data acquisition computer uses the balance formula to process the data and obtain the friction resistance acting on the surface of the floating element (3). The signal conditioning circuit is equipped with a dedicated regulated power supply and a control computer; the regulated power supply powers the signal conditioning circuit; the control computer is used to configure the parameters of the signal conditioning circuit. S30. Design of processing test methods; S31. Determine the response frequency and range of the semiconductor friction resistance balance (12) according to the test requirements; S32. The mode and force conditions of the semiconductor friction resistance balance (12) were analyzed by finite element method; S33. Optimize the structure of the semiconductor triboelectric balance (12); S34. Perform the processing and mounting of the semiconductor triboelectric balance (12); S35. Perform static calibration of the semiconductor friction resistance balance (12), obtain the balance formula of the semiconductor friction resistance balance (12), and determine the main coefficient and cross-interference coefficient of the balance formula; S36. Conduct wind tunnel tests and obtain aerodynamic loads using a semiconductor friction resistance balance (12); S37. Perform data processing, calculate the dynamic pressure value through wind tunnel flow field parameters, and use the dynamic pressure value to make the aerodynamic load dimensionless to obtain the friction drag coefficients of the longitudinal and transverse components; perform vector synthesis to obtain the magnitude and direction of the friction drag. S40. Data processing method for the influence of self-weight; During the movement of the experimental model (11), the angle between the direction of gravity of the experimental model (11) and the semiconductor friction resistance balance (12) and the axis of the semiconductor friction resistance balance (12) changes continuously, affecting the differential electrical signal output by the semiconductor friction resistance balance (12) and causing measurement errors caused by its own weight; the specific process is as follows: S41. In the absence of wind, the support mechanism of the hypersonic wind tunnel test section (10) is operated, and the angle of attack, sideslip angle and roll angle of the test model (11) are changed stepwise or continuously through the support mechanism; at the same time, the load of the semiconductor friction resistance balance (12) in motion is obtained, and the change in the attitude angle of the test model (11) on the reading of the semiconductor friction resistance balance (12) is obtained; S42. In the blowing state, the support mechanism of the hypersonic wind tunnel test section (10) is operated. The angle of attack, sideslip angle and roll angle of the test model (11) are changed stepwise or continuously through the support mechanism in the same way as S41, so as to obtain the load of the semiconductor friction resistance balance (12) in the blowing state. S43. Match the load obtained in S42 under the blowing state with the load obtained in S41 under the non-blowing state, add the corresponding self-weight correction amount, and then substitute it into the balance formula to calculate the aerodynamic load with self-weight influence. S44. Repeat S37 to obtain the magnitude and direction of the frictional resistance considering the influence of its own weight.

5. The method of using the semiconductor friction resistance balance according to claim 4, characterized in that, The support mechanism is an insert-type angle-of-attack mechanism. During the wind tunnel test, before the flow field is established, the test model (11) is kept outside the flow field. After the flow field stabilizes, the insert-type angle-of-attack mechanism drives the test model (11) into the flow field. Subsequently, the angle of attack, sideslip angle and roll angle of the test model (11) are changed stepwise or continuously through the insert-type angle-of-attack mechanism.

6. The method of using the semiconductor friction resistance balance according to claim 4, characterized in that, The finite element analysis includes frequency response analysis and static analysis of the semiconductor friction resistance balance (12); Frequency response analysis is used to obtain modal characteristics, with the aim of obtaining the vibration frequencies and mode shapes of the semiconductor friction resistance balance (12) to determine whether the semiconductor friction resistance balance (12) meets the requirements of wind tunnel testing. In hypersonic shock tunnels, the low-frequency modal frequencies of the semiconductor friction resistance balance (12) structure are required to be specific. f > 2 / t , t The effective test time of the wind tunnel is the time when the effective test time of the hypersonic shock wind tunnel is... t When the frequency is 10 ms, the lowest frequency of the semiconductor triboelectric balance (12) is greater than 200 Hz; Static analysis is used to calculate the response of the semiconductor friction resistance balance (12) structure under a fixed load. It is a key step in evaluating the sensitivity, linearity and anti-interference capability of the semiconductor friction resistance balance (12). Static analysis considers three types of loads: the first is friction resistance, which is the shear force acting on the floating element (3) parallel to the airflow direction; the second is airflow pressure, which is the pressure load perpendicular to the surface of the floating element (3); and the last is the torque load caused by the uneven pressure distribution perpendicular to the surface of the floating element (3).

7. The method of using the semiconductor friction resistance balance according to claim 4, characterized in that, In the static calibration process, the semiconductor friction resistance balance (12) is horizontally fixed and installed. Weights are suspended by a thin line fixed to the special calibration loading head to load the semiconductor friction resistance balance (12) in order to reduce the influence of pulley friction error and horizontal line error caused by conventional balance calibration methods.

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