Asymmetric pulsating pressure measuring device and method suitable for transonic flight fairing

Abstract

The invention discloses an asymmetric pulsating pressure measuring device and method suitable for a transonic flight fairing, and belongs to the technical field of information perception and recognition. The pressure sensitive circuit is used for collecting the external pulsating pressure of the fairing in the flight process, eliminating the internal pressure of the fairing through a through hole formed in the body, obtaining the pulsating pressure representing the internal and external pressure difference of the fairing, converting the pulsating pressure into an analog voltage signal and outputting the analog voltage signal to the signal conditioning circuit; the signal conditioning circuit receives the analog voltage signal, amplifies the analog voltage signal, and outputs the analog voltage signal to the filter circuit after zero setting; the filter circuit is used for filtering the signal and then outputting the signal; and the output interface circuit is used for conditioning the input signal to a voltage signal meeting a preset requirement and carrying out amplitude limiting so as to protect a rear-end acquisition circuit. The sensitive assembly based on the dry ceramic thick film capacitance pressure sensing principle is utilized, and the problems that in the prior art, pulsating pressure measurement is limited, and adaptability to industry and mining with static pressure changes is poor are solved.

Description

Technical Field

[0001] The present invention relates to a device and method for measuring asymmetric pulsating pressure of a fairing adapted to transonic flight, belonging to the technical field of information perception and recognition. Background Technique

[0002] All launch vehicles will face the "transonic flight" stage during flight. In the "transonic flight" stage, in order to prevent satellites or payloads from being affected by harmful environments such as aerodynamic force, aerodynamic heating, and acoustic vibration, a fairing is added outside the satellite or payload of the launch vehicle. The fairing not only protects the satellite or payload from the external environment during the "transonic flight" stage but also ensures that the overall rocket has a good aerodynamic shape, minimizing the windward resistance during the rocket's flight. With the changes in the shape and weight of the payload, the thrust requirements for launch vehicles are continuously increasing. No matter how the shape of the fairing changes, its most basic performance cannot change, and lightweight design is also required to improve the carrying capacity. This poses high requirements for the aerodynamic shape design of the fairing. Therefore, it has become an urgent need to master and understand the pulsating pressure borne by the fairing during the flight stage of the vehicle, especially during the "transonic flight" stage. However, at present, the measurement requirements for pulsating pressure in various parts of domestic rockets are mostly for symmetric pulsating pressure measurement under static pressure, which cannot truly reflect the situation of asymmetric pulsating pressure caused by different internal and external pressure differences borne by the fairing. Summary of the Invention

[0003] The technical problem solved by the present invention is: overcoming the deficiencies of the prior art, providing a device and method for measuring asymmetric pulsating pressure of a fairing adapted to transonic flight, and using a sensitive component based on the dry ceramic thick film capacitance pressure sensing principle to solve problems such as limited pulsating pressure measurement and poor adaptability to working conditions with changing static pressure in the prior art.

[0004] The technical solution of the present invention is: In the first aspect, a device for measuring asymmetric pulsating pressure of a fairing adapted to transonic flight includes:

[0005] A voltage reference source, which is used to receive an external power supply input and supply power to the internal modules of the measurement device after conversion;

[0006] A pressure-sensitive circuit, which is used to collect the pulsating pressure outside the fairing during flight, eliminate the pressure inside the fairing through the through holes provided on the body, obtain the pulsating pressure representing the internal and external pressure difference of the fairing, and convert the pulsating pressure into an analog voltage signal and then output it to the signal conditioning circuit;

[0007] A signal conditioning circuit, which receives the analog voltage signal, amplifies and zero-adjusts the analog voltage signal and then outputs it to the filtering circuit;

[0008] A filtering circuit, which is used to filter the input signal and then output it to the output interface circuit;

[0009] An output interface circuit for conditioning an input signal into a voltage signal that meets preset requirements and performing amplitude limiting to protect the backend acquisition circuit.

[0010] Further, the signal conditioning circuit uses an operational amplifier TLE2072 chip.

[0011] Further, pin 1 of the TLE2072 chip is connected to one end of resistor R1 and one end of resistor R2, and the other end of resistor R2 is connected to pin 2; the other end of resistor R1 is connected to pin resistor R5 and pin 6; the other end of resistor R5 is connected to pin 7 for the output of the signal conditioning circuit; pin 3 is connected to one end of resistor R3 and one end of resistor R6, the other end of resistor R3 is connected to the positive pole of the 5V power supply, and the other end of resistor R6 is grounded; pin 4 is connected to one end of capacitor C6 and the negative pole of the 15V power supply, and the other end of capacitor C6 is grounded; pin 5 is connected to resistor R8, and the other end of resistor R8 is connected to the input signal of the signal conditioning circuit; pin 8 is connected to one end of capacitor C1, and the other end of capacitor C1 is connected to the positive pole of the 15V power supply.

[0012] Further, the filtering circuit uses an operational amplifier TLE2074 chip.

[0013] Further, the input of the filtering circuit is connected to one end of resistor R11, and the other end of resistor R11 is connected to one end of resistor R14 and one end of capacitor C8; the other end of resistor R14 is connected to one end of capacitor C9 and pin 3 of operational amplifier D3, and the other end of capacitor C8 is connected to pin 1, pin 2 and one end of resistor R15 of operational amplifier D3; the other end of resistor R15 is connected to one end of resistor R16 and one end of capacitor C14, the other end of resistor R16 is connected to one end of capacitor C12 and pin 5 of operational amplifier D3, and the other end of capacitor C14 is connected to pin 6, pin 7 and one end of resistor R17 of operational amplifier D3; the other end of resistor R17 is connected to one end of resistor R18 and one end of capacitor C15, the other end of resistor R18 is connected to one end of capacitor C13 and pin 12 of operational amplifier D3, and the other end of capacitor C15 is connected to pin 10, pin 11 and one end of resistor R13 of operational amplifier D3; the other end of resistor R13 is connected to one end of resistor R12 and one end of capacitor C10, the other end of resistor R12 is connected to one end of capacitor C11 and pin 14 of operational amplifier D3, and the other end of capacitor C10 is connected to pin 15 of operational amplifier D3, one end of capacitor C7, one end of resistor R10 and one end of resistor R9; the other end of capacitor C7 is connected to the other end of resistor R10 and pin 16 of operational amplifier D3; the other end of resistor R9 outputs the signal of the filtering circuit; the other ends of capacitor C9, capacitor C12, capacitor C13 and capacitor C11 are grounded; pin 4 of operational amplifier D3 is connected to the positive pole of the 15V power supply; pin 13 of operational amplifier D3 is connected to the negative pole of the 15V power supply.

[0014] Furthermore, the pulsating pressure is Among them, the pulsating pressure root mean square value P rms It is calculated using the pulsating pressure time domain signal, where q is the flight pressure.

[0015] In a second aspect, a method for measuring asymmetric pulsating pressure using the asymmetric pulsating pressure measuring device includes:

[0016] Four measuring points are arranged in sequence on the shoulder of the fairing along the axial direction, and three measuring points are arranged in sequence on the center of the first-stage bottom baffle along the axial direction, and the measuring devices are arranged respectively;

[0017] During the flight of the aircraft, the measuring devices measure the pulsating pressure at their respective positions.

[0018] Furthermore, the four measuring points on the shoulder of the fairing are all located on one half of the fairing, respectively at: axial height 300 mm from the cone-column interface, axial height 600 mm from the cone-column interface, axial height 900 mm from the cone-column interface, and axial height 1200 mm from the cone-column interface.

[0019] Furthermore, when installing the measuring device, do not touch or use hard objects to contact the pressure-sensing diaphragm in the pressure measuring hole to avoid damaging the silicon sensitive surface and causing product failure.

[0020] Furthermore, the pressure measuring hole end of the measuring device is flush with the installation test surface.

[0021] The advantages of the present invention compared with the prior art are:

[0022] (1) The present invention brings reliability to the measurement of aerodynamic pressure on the outer surface of the fairing by the working mode of the sensitive element, and realizes accurate measurement of the pulsating pressure on the outer surface of the fairing by the design method of the internal and external pressure difference.

[0023] (2) The present invention improves the environmental adaptability and reliability of asymmetric pulsating pressure measurement by optimizing the internal structure design of the sensor and integrating the high-stability circuit design of products currently used in rockets. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0025] Figure 1 A functional block diagram of the asymmetric pulsating pressure measuring device of the present invention;

[0026] Figure 2This is the signal conditioning circuit diagram of the present invention;

[0027] Figure 3 This is the low-pass filter circuit diagram of the present invention. Detailed implementation manners

[0028] To better understand the above technical solution, the technical solution of the present invention will be described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations on the technical solution of the present invention. Without conflict, the technical features in the embodiments of the present invention and the embodiments can be combined with each other.

[0029] The following further details the asymmetric pulsating pressure measurement device and method for a fairing adapted to transonic flight provided by the embodiments of the present invention in conjunction with the accompanying drawings of the specification. The specific implementation manner may include: obtaining the external pulsating pressure of the fairing during flight by installing the asymmetric pulsating pressure measurement device at relevant positions on the fairing. Specifically, an asymmetric pulsating pressure measurement device for a fairing adapted to transonic flight includes:

[0030] A voltage reference source, which is used to receive an external power supply input and supply power to the internal modules of the measurement device after conversion;

[0031] A pressure-sensitive circuit, which is used to collect the external pulsating pressure of the fairing during flight, eliminate the internal pressure of the fairing through the through holes provided on the body, obtain the pulsating pressure representing the pressure difference inside and outside the fairing, and convert the pulsating pressure into an analog voltage signal and then output it to the signal conditioning circuit;

[0032] A signal conditioning circuit, which receives the analog voltage signal, amplifies and zero-adjusts the analog voltage signal and then outputs it to the filter circuit;

[0033] A filter circuit, which is used to filter the input signal and then output it to the output interface circuit;

[0034] An output interface circuit, which is used to condition the input signal to a voltage signal that meets the preset requirements and perform amplitude limiting to protect the subsequent acquisition circuit.

[0035] In the solution provided by the embodiments of the present invention, the circuit composition of an asymmetric pulsating pressure measurement device for a fairing adapted to transonic flight includes: a voltage reference source, a pressure-sensitive circuit, a signal conditioning circuit, a filter circuit, and an output interface circuit. The functional block diagram is as Figure 1 shown.

[0036] The voltage reference source consists of a reference source and a filter capacitor, which converts the external power supply of the product into a stable 5V reference voltage to supply power to other modules inside the measuring device. The circuit is provided with a pre - current - limiting resistor, which (1) provides over - current protection for the power supply; (2) reduces the voltage drop between the input and output of the reference source; (3) protects the system power supply; (4) improves the ability to resist electromagnetic interference.

[0037] The pressure - sensitive circuit is used to sensitively collect the pulsating pressure outside the fairing during flight, and through the through - holes set in the body, eliminate the influence of the pressure inside the fairing, and obtain the pulsating pressure signal representing the pressure difference between the inside and outside of the fairing. The dynamic range of the pulsating pressure signal sensitively collected by the pressure - sensitive circuit can be appropriately adjusted according to the theoretical analysis results or requirements; finally, the sensitized pulsating pressure signal is converted into an analog voltage signal through the built - in demodulation circuit and output to the subsequent signal conditioning circuit.

[0038] The signal conditioning circuit is composed of an operational amplifier TLE2072 and peripheral resistors and capacitors. The specific circuit is shown in Figure 2 as shown; this circuit is used to receive the analog voltage signal output by the pressure - sensitive circuit, and by setting the resistance and capacitance values in the adjustment circuit, amplify and zero - adjust the analog voltage signal. During the signal processing process, the level of pin 1 is used as the reference level, and finally, a voltage signal meeting the requirements is output to the subsequent filter circuit.

[0039] The filter circuit is composed of TLE2074 and resistors and capacitors, and is an eighth - order Butterworth low - pass filter, as shown in Figure 3 as shown, which is used to filter the output signal of the signal conditioning circuit; during the filtering process, by setting the resistance and capacitance values in the adjustment circuit, the output signal meets the requirements of a bandwidth of 0 - 60Hz, with the in - band ripple less than 1dB in the range of 0 - 50Hz and the out - of - band attenuation greater than 36dB; and the filtered signal is connected to a protection resistor and then output to the output interface circuit.

[0040] Pin 1 of the TLE2072 chip is connected to one end of resistor R1 and one end of resistor R2, and the other end of resistor R2 is connected to pin 2; the other end of resistor R1 is connected to pin resistor R5 and pin 6; the other end of resistor R5 is connected to pin 7, which is used for the output of the signal conditioning circuit; pin 3 is connected to one end of resistor R3 and one end of resistor R6, the other end of resistor R3 is connected to the positive pole of the 5V power supply, and the other end of resistor R6 is grounded; pin 4 is connected to one end of capacitor C6 and the negative pole of the 15V power supply, and the other end of capacitor C6 is grounded; pin 5 is connected to resistor R8, and the other end of resistor R8 is connected to the input signal of the signal conditioning circuit; pin 8 is connected to one end of capacitor C1, and the other end of capacitor C1 is connected to the positive pole of the 15V power supply.

[0041] The output interface circuit is used to condition the input signal into a voltage signal that meets the preset requirements and perform amplitude limiting, so as to achieve the usage requirements that the positive amplitude-limiting voltage is not greater than 6.5V and the negative amplitude-limiting voltage is not less than -0.7V, playing a role in protecting the backend acquisition circuit. At the same time, a resistor with the set requirements is connected in series at the output port to protect the internal circuit of the measuring device.

[0042] One end of the input of the filter circuit is connected to one end of resistor R11, and the other end of resistor R11 is connected to one end of resistor R14 and one end of capacitor C8; the other end of resistor R14 is connected to one end of capacitor C9 and pin 3 of operational amplifier D3, and the other end of capacitor C8 is connected to pin 1, pin 2 of operational amplifier D3 and one end of resistor R15; the other end of resistor R15 is connected to one end of resistor R16 and one end of capacitor C14, the other end of resistor R16 is connected to one end of capacitor C12 and pin 5 of operational amplifier D3, and the other end of capacitor C14 is connected to pin 6, pin 7 of operational amplifier D3 and one end of resistor R17; the other end of resistor R17 is connected to one end of resistor R18 and one end of capacitor C15, the other end of resistor R18 is connected to one end of capacitor C13 and pin 12 of operational amplifier D3, and the other end of capacitor C15 is connected to pin 10, pin 11 of operational amplifier D3 and one end of resistor R13; the other end of resistor R13 is connected to one end of resistor R12 and one end of capacitor C10, the other end of resistor R12 is connected to one end of capacitor C11 and pin 14 of operational amplifier D3, and the other end of capacitor C10 is connected to pin 15 of operational amplifier D3, one end of capacitor C7, one end of resistor R10 and one end of resistor R9; the other end of capacitor C7 is connected to the other end of resistor R10 and pin 16 of operational amplifier D3; the other end of resistor R9 outputs the signal of the filter circuit; the other ends of capacitor C9, capacitor C12, capacitor C13 and capacitor C11 are grounded; pin 4 of operational amplifier D3 is connected to the positive pole of the 15V power supply; pin 13 of operational amplifier D3 is connected to the negative pole of the 15V power supply.

[0043] In the above circuit design process, the thermal environment conditions during the flight process are fully considered, and devices with low power consumption, small heat dissipation and a wide temperature environment tolerance range are selected. Such as resistors, capacitors and monolithic integrated circuits, which are required to have a temperature tolerance range of -55°C to +125°C and work stably under high and low temperature conditions; sensitive components should select devices with a small temperature coefficient. At the same time, derating use is carried out in accordance with GJB / Z 35-93 "Component Derating Criteria", and all components meet Class I derating, and the derating of key components reaches 0.3, which is much higher than Class I derating.

[0044] According to the high-precision pulsating pressure telemetry data obtained by the measuring device, the root mean square coefficient and power spectral density of the pulsating pressure of the telemetry result are processed.

[0045] The root mean square pulsating pressure represents the total energy of the transmitted disturbance in the rocket surface boundary layer, and its definition formula is formula (1):

[0046]

[0047] P LU —— Local unsteady pressure;

[0048] P LS —— Time-average value of local unsteady pressure;

[0049] T —— Sampling time.

[0050] The pulsating pressure coefficient reflects the strength of the pulsating pressure. The pulsating pressure coefficient obtained by the measurement device described in this article is expressed in percentage form, and its definition is shown in Formula (2):

[0051]

[0052] In the formula, the root mean square value of pulsating pressure P rms is calculated from the pulsating pressure time-domain signal, and q is the flight pulsating pressure.

[0053] Use the described asymmetric pulsating pressure measurement device to measure the asymmetric pulsating pressure of the fairing and other parts during flight. Arrange 4 measuring points in sequence along the axial direction at the shoulder of the fairing, and arrange 3 measuring points in sequence along the axial direction at the center of the bottom baffle of the first stage, respectively for completing the pulsating pressure at the installation positions of each measuring device during the flight of the aircraft.

[0054] The 4 measuring points arranged on the shoulder of the fairing are all installed on the pointed arch-shoulder shell section of one side half-shell of the fairing (on the Ⅰ half-shell) to identify the pulsating pressure load of the fairing; to obtain the position where the pulsating pressure peak of the fairing appears, the 4 measuring points are arranged in sequence along the axial direction at the shoulder, and the axial heights are staggered with those of the conventional pulse pressure sensors, and are respectively located at: 300 mm from the cone-cylinder interface in axial height, 600 mm from the cone-cylinder interface in axial height, 900 mm from the cone-cylinder interface in axial height, and 1200 mm from the cone-cylinder interface in axial height.

[0055] After selecting the installation position of the measuring device, install it according to the usage requirements of the measuring device. Before installation, check the appearance of the measuring device to ensure that there are no scratches, scuffs and corrosion marks that affect the product performance; there are no burrs, rust and damage on the outer surface and installation parts, and the connectors are in reliable contact; the markings are clear, complete and accurate, and there is no oil stain in the pressure measuring hole. During installation, it is prohibited to touch or contact the pressure-sensitive diaphragm in the pressure measuring hole with hard objects to avoid damaging the silicon sensitive surface and causing the product to fail; it is required that the end face of the pressure measuring hole is flush with the installation and test surface to reduce the influence on the test results caused by the uneven outer surface.

[0056] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

[0057] The content not described in detail in the specification of the present invention belongs to the well-known technology of those skilled in the art.

Claims

1. A fairing asymmetric pulsating pressure measurement device adapted to transonic flight, characterized in that, Comprising: A voltage reference source for receiving an external power input, converting it, and supplying power to the internal modules of the measuring device; A pressure-sensitive circuit for collecting the pulsating pressure outside the fairing during flight, eliminating the internal pressure of the fairing through the through holes provided on the body, obtaining the pulsating pressure representing the pressure difference inside and outside the fairing, and converting the pulsating pressure into an analog voltage signal and outputting it to the signal conditioning circuit; A signal conditioning circuit for receiving the analog voltage signal, amplifying and zero-adjusting the analog voltage signal, and then outputting it to the filtering circuit; A filtering circuit for filtering the input signal and then outputting it to the output interface circuit; An output interface circuit for conditioning the input signal to a voltage signal meeting the preset requirements and performing amplitude limiting to protect the backend acquisition circuit.

2. The asymmetric pulsating pressure measurement device for fairings adapted to transonic flight according to claim 1, characterized in that The signal conditioning circuit uses an operational amplifier TLE2072 chip.

3. The asymmetric pulsating pressure measurement device for fairings adapted to transonic flight according to claim 1, wherein Pin 1 of the TLE2072 chip is connected to one end of resistor R1 and one end of resistor R2, and the other end of resistor R2 is connected to pin 2; the other end of resistor R1 is connected to pin resistor R5 and pin 6; the other end of resistor R5 is connected to pin 7 for the output of the signal conditioning circuit; pin 3 is connected to one end of resistor R3 and one end of resistor R6, the other end of resistor R3 is connected to the positive pole of the 5V power supply, and the other end of resistor R6 is grounded; pin 4 is connected to one end of capacitor C6 and the negative pole of the 15V power supply, and the other end of capacitor C6 is grounded; pin 5 is connected to resistor R8, and the other end of resistor R8 is connected to the input signal of the signal conditioning circuit; pin 8 is connected to one end of capacitor C1, and the other end of capacitor C1 is connected to the positive pole of the 15V power supply.

4. The asymmetric pulsating pressure measurement device for fairings adapted to transonic flight according to claim 3, characterized in that, The filtering circuit uses an operational amplifier TLE2074 chip.

5. The asymmetric pulsating pressure measurement device for fairings adapted to transonic flight according to claim 4, wherein One end of a resistor R11 is connected to the input of the filter circuit, and the other end of the resistor R11 is connected to one end of a resistor R14 and one end of a capacitor C8; the other end of the resistor R14 is connected to one end of a capacitor C9 and pin 3 of an operational amplifier D3, and the other end of the capacitor C8 is connected to pin 1, pin 2 of the operational amplifier D3 and one end of a resistor R15; the other end of the resistor R15 is connected to one end of a resistor R16 and one end of a capacitor C14, the other end of the resistor R16 is connected to one end of a capacitor C12 and pin 5 of the operational amplifier D3, and the other end of the capacitor C14 is connected to pin 6, pin 7 of the operational amplifier D3 and one end of a resistor R17; the other end of the resistor R17 is connected to one end of a resistor R18 and one end of a capacitor C15, the other end of the resistor R18 is connected to one end of a capacitor C13 and pin 12 of the operational amplifier D3, and the other end of the capacitor C15 is connected to pin 10, pin 11 of the operational amplifier D3 and one end of a resistor R13; the other end of the resistor R13 is connected to one end of a resistor R12 and one end of a capacitor C10, the other end of the resistor R12 is connected to one end of a capacitor C11 and pin 14 of the operational amplifier D3, and the other end of the capacitor C10 is connected to pin 15 of the operational amplifier D3, one end of a capacitor C7, one end of a resistor R10 and one end of a resistor R9; the other end of the capacitor C7 is connected to the other end of the resistor R10 and pin 16 of the operational amplifier D3; the other end of the resistor R9 outputs the signal of the filter circuit; the other ends of the capacitor C9, the capacitor C12, the capacitor C13 and the capacitor C11 are grounded; pin 4 of the operational amplifier D3 is connected to the positive pole of a 15V power supply; pin 13 of the operational amplifier D3 is connected to the negative pole of the 15V power supply.

6. The asymmetric pulsating pressure measurement device for fairings adapted to transonic flight according to claim 1, wherein The pulsating pressure is where the root mean square value of the pulsating pressure is P rms calculated from the time-domain signal of the pulsating pressure, and q is the dynamic pressure of flight.

7. An asymmetric pulsating pressure measurement method implemented by using the described asymmetric pulsating pressure measurement device, characterized in that, Including: Four measuring points are arranged in sequence along the axial direction at the shoulder of the fairing, and three measuring points are arranged in sequence along the axial direction at the center of the bottom baffle of the first stage, and the measuring devices are respectively arranged. During the flight of the aircraft, the measuring devices respectively measure the pulsating pressure at their respective positions.

8. The measurement method according to claim 7, characterized in that The four measuring points at the shoulder of the fairing are all located on one side half fairing of the fairing, and are respectively located at: the axial height is 300mm away from the cone-column interface, the axial height is 600mm away from the cone-column interface, the axial height is 900mm away from the cone-column interface, and the axial height is 1200mm away from the cone-column interface.

9. The measuring method according to claim 7, wherein When installing the measuring device, do not touch or contact the pressure-sensitive diaphragm in the pressure measuring hole with hard objects to avoid damaging the silicon sensitive surface and causing product failure.

10. The measurement method according to claim 7, wherein The pressure measuring hole end of the measuring device is flush with the installation test surface.

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