A method and device for measuring the gas-liquid interface of a liquid jet in a closed environment

Abstract

The present application provides a method and device for measuring the gas-liquid interface of a liquid jet in a closed environment, which relates to the field of measurement technology, including: obtaining the position of an ultrasonic detector in a target closed environment and a reference ultrasonic signal and a target ultrasonic signal detected by the ultrasonic detector in the closed environment; the reference ultrasonic signal and the target ultrasonic signal are ultrasonic signals collected when there is no jet in the target closed environment and when there is a jet in the target closed environment respectively; based on the reference ultrasonic signal and the target ultrasonic signal, a scattering signal and corresponding scattering information are obtained; from a pre-constructed scattering information database storing different scattering information and different positions and corresponding scattering body sizes, the target scattering body size corresponding to the scattering information and position is matched; the target scattering body size is the size of the scattering body that generates the jet. The present application can realize the dynamic measurement of the gas-liquid interface of the jet in a closed combustion chamber.

Description

Technical Field

[0001] The present application relates to the field of measurement technology, and in particular to a method and device for measuring a gas-liquid interface of a liquid jet in a closed environment. Background Art

[0002] Unstable combustion is one of the major scientific and technological challenges faced in the development of aviation and aerospace engines. Under conditions of high temperature, high pressure and high energy density, flow, combustion and acoustic disturbances are easily coupled, resulting in rapid pulsation of combustion chamber pressure and heat release, causing ablation of engine components and even explosion. The unstable combustion of liquid rocket engines is mainly caused by the coupling of sound waves, flow and heat release rate. Among them, the fluctuation of the jet gas-liquid interface is one of the sources of unstable combustion. Real-time monitoring of it can reveal the coupling mechanism of unstable combustion on the one hand, and on the other hand, it is also conducive to improving the control ability of unstable combustion.

[0003] However, due to the high temperature and high pressure closed environment in the engine combustion chamber, many existing high-precision measurement methods cannot be used. First of all, contact measurement methods cannot be used. In addition, traditional optical methods such as backlight method, shadow method, schlieren method and laser induced fluorescence method can achieve accurate measurement in laboratory models, but when applied to the combustion chamber, it is necessary to open an optical window on the wall of the combustion chamber, which is difficult to achieve on a real rocket engine. In addition, some new metal-penetrating measurement methods such as X-ray detection, terahertz wave measurement and electromagnetic fluid measurement methods cannot be truly applied to the measurement of the gas-liquid interface in the combustion chamber due to the relationship between penetration ability and gas conductivity. Therefore, there is currently no available measurement method for the gas-liquid interface in the combustion chamber.

[0004] The existing ultrasonic measurement methods are mainly used in non-destructive testing, medical testing, hydroacoustic testing and gas temperature field testing. Currently, there is no technology that can apply ultrasonic testing to the measurement of gas-liquid interface in the combustion chamber. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide a method and device for measuring the gas-liquid interface of a liquid jet in a closed environment, so as to solve the above-mentioned problems existing in the prior art, and to realize dynamic measurement of the gas-liquid interface of a liquid jet in a closed environment without opening an optical window.

[0006] In a first aspect, a method for measuring a gas-liquid interface of a liquid jet in a closed environment is provided, and the method may include:

[0007] Acquire the position of the ultrasonic detector in the target enclosed environment and the reference ultrasonic signal and the target ultrasonic signal detected by the ultrasonic detector in the enclosed environment; wherein the reference ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector in the target enclosed environment when there is no jet in the first preset time period; and the target ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector in the target enclosed environment when there is a jet in the second preset time period;

[0008] Based on the reference ultrasonic signal and the target ultrasonic signal, acquiring a scattered signal and corresponding scattering information;

[0009] The target scatterer size corresponding to the scattering information and the position is matched from a pre-constructed scattering information database; wherein the target scatterer size is the size of the scatterer that generates the jet; the scattering information database includes: different scattering information and different positions and corresponding scatterer sizes.

[0010] In an optional implementation, any target ultrasonic signal and any reference ultrasonic signal correspond to a collection time;

[0011] The starting time of the first preset time period and the second preset time period are both the time when ultrasonic waves are started to be emitted in the target closed environment.

[0012] In an optional implementation, after acquiring the reference ultrasonic signal and the target ultrasonic signal in the target closed environment, the method further includes:

[0013] Performing signal window processing on the reference ultrasonic signal and the target ultrasonic signal to obtain a processed target ultrasonic signal and a processed reference ultrasonic signal;

[0014] The time of transmitting the ultrasonic wave in the target closed environment is taken as the zero point, and the acquisition time of the processed target ultrasonic wave signal and the processed reference ultrasonic wave signal are aligned.

[0015] In an optional implementation, acquiring a scattered signal and corresponding scattering information based on the reference ultrasonic signal and the target ultrasonic signal includes:

[0016] For any acquisition time, a target voltage value and a reference voltage value are obtained; wherein the target voltage value is a voltage value corresponding to the target ultrasonic signal corresponding to the acquisition time; and the reference voltage value is a voltage value corresponding to the reference ultrasonic signal corresponding to the acquisition time;

[0017] Subtracting the reference voltage value from the target voltage value to obtain a scattering signal corresponding to the acquisition time;

[0018] Scattering information is extracted from the scattering signal to obtain scattering information corresponding to the acquisition time.

[0019] In an optional implementation, extracting scattering information from the scattering signal to obtain the scattering information corresponding to the acquisition time includes:

[0020] Extracting a plurality of pulse scattered wave packets from the scattered signal;

[0021] The first pulse scattering wave packet extracted is used as the target pulse scattering wave packet;

[0022] Performing a Hilbert transform on the target pulse scattering wave packet to obtain an envelope of the target pulse scattering wave packet;

[0023] Based on the envelope, scattering information corresponding to the acquisition time is determined.

[0024] In an optional implementation, the scattering information includes: scattering intensity;

[0025] Matching the scattering information and the target scatterer size corresponding to the position from a pre-built scattering information database includes:

[0026] The scattering intensity and the target scatterer size corresponding to the position are matched from a pre-constructed scattering information database.

[0027] In a second aspect, a device for measuring a gas-liquid interface of a liquid jet in a closed environment is provided, and the device may include:

[0028] an acquisition unit, used to acquire the position of the ultrasonic detector in the target closed environment and a reference ultrasonic signal and a target ultrasonic signal detected by the ultrasonic detector in the closed environment; wherein the reference ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector when there is no jet in the target closed environment within a first preset time period; and the target ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector when there is a jet in the target closed environment within a second preset time period;

[0029] a determination unit, configured to acquire a scattered signal and corresponding scattering information based on the reference ultrasonic signal and the target ultrasonic signal;

[0030] A matching unit is used to match the scattering information and the target scatterer size corresponding to the position from a pre-constructed scattering information database; wherein the target scatterer size is the size of the scatterer that generates the jet; the scattering information database includes: different scattering information and different positions and corresponding scatterer sizes.

[0031] In a third aspect, an electronic device is provided, the electronic device comprising a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus;

[0032] Memory, used to store computer programs;

[0033] The processor is used to implement any method step described in the first aspect when executing the program stored in the memory.

[0034] In a fourth aspect, a computer-readable storage medium is provided, wherein a computer program is stored in the computer-readable storage medium, and when the computer program is executed by a processor, any method step described in the first aspect is implemented.

[0035] The present application realizes the measurement of the gas-liquid interface of a liquid jet in a closed environment by using ultrasound, overcoming the defect that the optical measurement method in the prior art requires an optical window to be opened on the wall of the closed environment or the wall must be a transparent wall. It is not affected by the shielding effect of the gas mixture outside the jet, and only requires a very small ultrasonic pressure measuring hole to realize the dynamic measurement of the gas-liquid interface of the jet in the closed combustion chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 A flow chart of a method for measuring a gas-liquid interface of a liquid jet in a closed environment provided in an embodiment of the present application;

[0038] Figure 2 A schematic diagram of a method for measuring a gas-liquid interface of a liquid jet in a closed environment provided in an embodiment of the present application;

[0039] Figure 3 A schematic diagram of a reference ultrasonic signal measured in a closed environment without scatterers provided in an embodiment of the present application;

[0040] Figure 4 A schematic diagram of the positions of various ultrasonic detectors in a closed environment provided in an embodiment of the present application;

[0041] Figure 5 A schematic diagram of a reference ultrasonic signal measured in a closed environment with a scatterer provided in an embodiment of the present application;

[0042] Figure 6 A flowchart of a scattering information extraction method provided in an embodiment of the present application;

[0043] Figure 7 A schematic diagram of a scattered signal provided in an embodiment of the present application;

[0044] Figure 8 A schematic diagram of performing cross-correlation operation on multiple scattered signals to determine time and cross-correlation coefficients provided in an embodiment of the present application;

[0045] Figure 8 (a) is a schematic diagram of scattered signals received by two ultrasonic detectors at different positions provided in an embodiment of the present application;

[0046] Figure 8 (b) is a schematic diagram of the result of cross-correlation calculation of scattered signals received by two ultrasonic detectors at different positions provided in an embodiment of the present application;

[0047] Fig. 9 A schematic diagram of envelope extraction and acoustic energy analysis of local scattering data provided in an embodiment of the present application;

[0048] Fig.10 A graph showing the relationship between the diameter of a fixed scatterer in a closed environment and the relative scattered sound pressure obtained by ultrasonic detectors at different positions provided in an embodiment of the present application;

[0049] Fig.11 A comparison diagram of ultrasonic and optical measurement results of a jet gas-liquid interface in a closed environment provided in an embodiment of the present application;

[0050] Fig.11 (a) is a comparison diagram of scatterer sizes obtained by ultrasonic and optical measurements of the jet gas-liquid interface in a closed environment provided in an embodiment of the present application;

[0051] Fig.11 (b) is the frequency information of the jet gas-liquid interface fluctuations of the ultrasonic measurement method and the optical measurement method provided in the embodiments of the present application;

[0052] Fig.11 (c) is a relative measurement error diagram of the ultrasonic measurement method and the optical measurement method provided in the embodiment of the present application;

[0053] Fig.12 A schematic diagram of the structure of a device for measuring the gas-liquid interface of a liquid jet in a closed environment provided in an embodiment of the present application;

[0054] Fig.13 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0056] The method for measuring the gas-liquid interface of a liquid jet in a closed environment provided in the embodiment of the present application can be applied in a server or in a terminal with strong computing power. The server can be a physical server, a server cluster or a distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, content delivery networks (Content Delivery Network, CDN), and big data and artificial intelligence platforms. The terminal can be a user equipment (User Equipment, UE) such as a mobile phone, a smart phone, a laptop, a digital broadcast receiver, a personal digital assistant (PDA), a tablet computer (PAD), a handheld device, a vehicle-mounted device, a wearable device, a computing device or other processing equipment connected to a wireless modem, a mobile station (Mobile Station, MS), a mobile terminal (Mobile Terminal), etc. The terminal and the server can be directly or indirectly connected by wired or wireless communication, which is not limited in this application.

[0057] The preferred embodiments of the present application are described below in conjunction with the drawings in the specification. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In addition, the embodiments and features in the embodiments of the present application may be combined with each other if there is no conflict.

[0058] Figure 1 The present invention provides a flow chart of a method for measuring the gas-liquid interface of a liquid jet in a closed environment. Figure 1 As shown, the method may include:

[0059] Step S110, obtaining the position of the ultrasonic detector in the target enclosed environment and the reference ultrasonic signal and the target ultrasonic signal detected by the ultrasonic detector in the target enclosed environment; based on the reference ultrasonic signal and the target ultrasonic signal, obtaining the scattered signal and the corresponding scattering information.

[0060] In the embodiment of the present application, the target closed environment is a closed gas environment (ie, a closed combustion chamber).

[0061] In the embodiment of the present application, a plurality of ultrasonic sensors are arranged in the target closed environment, i.e., the closed combustion chamber, and the plurality of ultrasonic sensors include a generator and one or more ultrasonic detectors; the detection range of all ultrasonic detectors in the closed combustion chamber can cover the entire closed combustion chamber. When the number of ultrasonic detectors is 1, the placement angle of the ultrasonic detector can be determined according to the scattering principle so that the detection range of the ultrasonic detector covers the entire closed combustion chamber.

[0062] In the embodiment of the present application, the position of the ultrasonic detector for collecting the reference ultrasonic signal and the position of the ultrasonic detector for collecting the target ultrasonic signal corresponding to the reference ultrasonic signal are the same.

[0063] In an embodiment of the present application, the reference ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector when there is no jet in the target closed environment within a first preset time period. The method for obtaining the reference ultrasonic signal includes: when there is no jet in the target closed environment (that is, no scatterer is provided), controlling the ultrasonic generator to emit an ultrasonic signal at a preset time interval or continuously, and using an ultrasonic detector set at a fixed position or a known position to capture ultrasonic signals reflected from different directions and distances to obtain a reference ultrasonic signal.

[0064] In an embodiment of the present application, the target ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector when a jet exists in the target closed environment within a second preset time period; the method for acquiring the target ultrasonic signal includes: setting a scatterer in the target closed environment, at which time a jet exists in the target closed environment, controlling the ultrasonic generator to emit an ultrasonic signal again at a preset time interval or continuously, and using an ultrasonic detector set at the same position as when collecting the reference ultrasonic wave signal to capture ultrasonic signals reflected from different directions and distances to obtain the target ultrasonic signal.

[0065] In the embodiment of the present application, in the process of collecting the target ultrasonic signal, due to the presence of scatterers (including jets) in the target closed environment, there will be obvious scattered waves, which will be received by ultrasonic detectors at different positions; at this time, the ultrasonic signal received by the ultrasonic detector includes: the original signal emitted by the ultrasonic generator, the scattered signal and the signal reflected multiple times by the inner wall of the target closed environment; therefore, it is difficult to directly extract the scattered signal from the received ultrasonic signal.

[0066] In the embodiment of the present application, any target ultrasonic signal and any reference ultrasonic signal correspond to an acquisition time; the starting time of the first preset time period and the second preset time are both the time when ultrasonic waves start to be emitted in the target closed environment, and are also the time when ultrasonic waves occur in the target closed environment.

[0067] In the embodiment of the present application, the signal used for ultrasonic measurement is a short pulse signal, which can be a short pulse variable frequency or variable amplitude signal; when the ultrasonic signal is collected, a trigger signal output to the ultrasonic generator will be additionally collected synchronously, and the trigger signal is the time to start emitting ultrasonic waves in the target closed environment.

[0068] In an embodiment of the present application, after obtaining a reference ultrasonic signal, it is necessary to perform an error estimation on the obtained reference ultrasonic signal and screen the best reference ultrasonic signal. The specific steps include: obtaining a sufficient number of reference ultrasonic signals through multiple measurements; determining the repeatability, maximum absolute error and mean absolute error of the obtained reference ultrasonic signal through reference ultrasonic signal subtraction and cross-correlation algorithm, and determining the best reference ultrasonic signal through local and global averaging. The best reference ultrasonic signal should have the smallest absolute error.

[0069] In the embodiment of the present application, after obtaining the reference ultrasonic signal and the target ultrasonic signal in the target closed environment, it is necessary to unify the zero points of the reference ultrasonic signal and the target ultrasonic signal. The specific steps include:

[0070] The reference ultrasonic signal and the target ultrasonic signal are subjected to signal window processing to obtain a processed target ultrasonic signal and a processed reference ultrasonic signal; the time of transmitting the ultrasonic wave in the target closed environment is taken as the zero point, and the acquisition time of the processed target ultrasonic signal and the processed reference ultrasonic signal are aligned.

[0071] In the embodiment of the present application, based on the reference ultrasonic signal and the target ultrasonic signal, obtaining the scattered signal and the corresponding scattered information includes:

[0072] For any acquisition time, obtain the target voltage value and the reference voltage value; subtract the reference voltage value from the target voltage value to obtain the scattering information corresponding to the acquisition time; specifically, the target voltage value is the voltage value corresponding to the target ultrasonic signal corresponding to the acquisition time; the reference voltage value is the voltage value corresponding to the reference ultrasonic signal corresponding to the acquisition time.

[0073] In an embodiment of the present application, the difference between the voltage value of an ultrasonic signal with a scattered signal and the voltage value of an ultrasonic signal without a scattered signal, which are collected at the same collection time and in the same environment using an ultrasonic detector set at the same position in the same closed environment, is considered to be a scattered signal; since the reference ultrasonic signal and the target ultrasonic signal are consistent in other variables except the scattered signal, the voltage difference is actually the scattered signal.

[0074] In an embodiment of the present application, when multiple ultrasonic detectors are provided, the acquisition of scattered signals includes: for any ultrasonic detector, subtracting a reference voltage value corresponding to a reference ultrasonic signal collected by the ultrasonic detector at the corresponding collection time from a target voltage value corresponding to a target ultrasonic signal collected by the ultrasonic detector at each collection time, to obtain the scattered signals corresponding to the ultrasonic detector at different collection times.

[0075] In the embodiment of the present application, when multiple ultrasonic detectors are provided, it is necessary to determine the accuracy of scattered wave extraction for the scattered signals corresponding to different ultrasonic detectors through a cross-correlation algorithm to perform error estimation; the specific steps include: the two main determination parameters are the cross-correlation coefficient and the time difference between the scattered wave packets obtained by the two receivers. Theoretically, the cross-correlation coefficient should be 1, and the time difference is related to the relative position of the receiver. Based on this cross-correlation calculation, the accuracy of the above-mentioned scattered wave extraction process can be evaluated to ensure that the extracted scattered waves can reflect the geometric characteristics of the scatterer. In the embodiment of the present application, when the target ultrasonic signal and the reference ultrasonic signal are subtracted, the corresponding ultrasonic trigger signal will be subtracted at the same time. Since the ultrasonic trigger signals corresponding to the target ultrasonic signal and the reference ultrasonic signal are completely consistent, the subtraction result of the ultrasonic trigger signal can be used to evaluate the error in the data processing process. In addition, the above-mentioned scattered wave extraction process can also be evaluated for error based on the principle of scattering. Since the existing scattering principle believes that: the scattered wave is a wave emitted by the scatterer, the waveform of the scattered wave signal collected by the receivers at different angles should be exactly the same, and the time of the collected scattered wave is negatively correlated with its position from the scatterer. Based on this principle, the scattered wave signals collected by different receivers can be cross-correlated, the similarity between the scattered waves can be described by the cross-correlation coefficient, and the time delay between the scattered waves can be described by the position of the maximum cross-correlation coefficient. Combining the above two methods can realize the error evaluation of the scattered wave extraction process, and optimize the above scattered wave extraction process based on the error.

[0076] In the embodiment of the present application, scattering information is extracted from the scattering signal to obtain scattering information corresponding to the acquisition time, including:

[0077] Extract multiple pulse scattering wave packets from the scattering signal; use the first extracted pulse scattering wave packet as the target pulse scattering wave packet; perform Hilbert transform on the target pulse scattering wave packet to obtain the envelope of the target pulse scattering wave packet; and determine the scattering information corresponding to the acquisition time based on the envelope.

[0078] In the embodiment of the present application, multiple pulse scattered wave packets are extracted from the scattered signal, including:

[0079] The time length of the scattered wave packet is determined according to the ultrasonic trigger signal and the ultrasonic propagation time; based on the time length of the scattered wave packet, a plurality of pulse scattered wave packets are extracted from the scattered signal.

[0080] In the embodiment of the present application, the time length of the scattered wave packet should generally not be less than the time from when the ultrasonic wave is emitted from the generator (ie, the ultrasonic trigger signal) to when the probe receives the scattered wave (ie, the ultrasonic wave propagation time).

[0081] In an embodiment of the present application, based on the envelope, determining the scattering information corresponding to the acquisition time includes: performing time integration on the envelope to obtain the corresponding scattering intensity.

[0082] In the embodiment of the present application, determining the scattering information corresponding to the acquisition time based on the envelope may include:

[0083] Integrate the envelope to obtain acoustic energy data of the envelope; use the acoustic energy data of the envelope as the scattering intensity corresponding to the acquisition time;

[0084] Or, the peak value of the envelope is taken as the scattering intensity corresponding to the acquisition time;

[0085] Or, the acoustic energy data of the envelope and the peak value of the envelope are weighted averaged to obtain the scattering intensity corresponding to the acquisition time. In the embodiment of the present application, the scattering intensity value is determined based on the actual measurement conditions.

[0086] Step S120: Match the scattering information and the target scatterer size corresponding to the position from the pre-built scattering information database.

[0087] In an embodiment of the present application, the scattering information database includes: different scattering information and different positions and scatterer sizes corresponding to different scattering information; specifically, the scattering information database includes: different scattering intensities, different positions and corresponding scattering intensities and scatterer sizes corresponding to the corresponding positions.

[0088] In the embodiments of the present application, whether only one ultrasonic detector is provided or multiple ultrasonic detectors are provided, when the ultrasonic detector is located at different positions, the signals received are different, the corresponding scattering intensities are also different, and the sizes of the scatterers matched thereby are also different; therefore, the scattering information database contains the sizes of scatterers corresponding to a certain scattering intensity detected by the ultrasonic detector when it is located at different positions.

[0089] In the embodiment of the present application, the scattering information database does not store the number of ultrasonic detectors, but only stores the position of the ultrasonic detectors and the scattering intensity, and matches the size of the scatterer; that is, when there is only one ultrasonic detector in a closed environment, what is finally obtained is the scattering intensity corresponding to the ultrasonic detector located at that position, and the corresponding scatterer size; when there are multiple ultrasonic detectors in a closed environment, what is finally obtained are multiple scattering intensities corresponding to multiple ultrasonic detectors located at different positions, and multiple initial sizes of the scatterers matched based on the position and intensity.

[0090] In practical applications, since only the size of one scatterer needs to be obtained in the end, it is also necessary to process the multiple initial sizes of the scatterer obtained above and then perform weighted averaging to obtain the final size of the scatterer.

[0091] In one embodiment of the present application, processing the multiple initial sizes includes: removing abnormal values ​​using an average value or a standard deviation or a model, etc., to obtain a plurality of processed sizes.

[0092] In one embodiment of the present application, a weighted average is taken for multiple processed sizes, including: determining a weight value of each processed size based on the theoretical scattering intensity at each angle, and obtaining a final scatterer size based on the weight value of each processed size and the corresponding size.

[0093] In practical applications, the scattering intensity is actually related to the relative position (including distance and angle, etc.) between the ultrasonic detector and the scatterer in a closed environment, as well as the relative position between the ultrasonic detector and the ultrasonic generator in a closed environment. Through many experiments, it can be found that when the relative angle between the ultrasonic detector and the scatterer is a certain value, its accuracy is higher; based on this, different weights are set for the scatterer sizes detected at different positions, thereby improving the accuracy of the final result.

[0094] In the embodiment of the present application, the position of the ultrasonic detector in the target closed environment may be an actual position or a relative position between the ultrasonic detector and the ultrasonic generator and / or the scatterer.

[0095] In an embodiment of the present application, a method for constructing a scattering information database includes:

[0096] First, multiple measurements will be made on scatterers of different fixed sizes to obtain data of sufficient size (the size interval is as small as possible to improve accuracy); secondly, the experimental error evaluation method is to measure multiple times for a single scatterer of a certain size. Since the size and position of the scatterer are fixed at this time, the scattering information obtained by the scattering signal extraction module on each receiver (i.e., ultrasonic detector) should also be the same when the experiment is repeated. Therefore, the results of multiple measurements will be evaluated for absolute and relative errors, and the data extraction module of the scattering signal will be optimized based on the error evaluation results. Finally, the specific method of theoretical error evaluation is that since scatterers of different fixed sizes are measured in the experiment, and in acoustic theory, at different measurement angles, the size of the scatterer and the intensity of the scattering signal have a certain theoretical relationship. Based on this theoretical relationship, the results of experimental measurements of scatterers of different angles (different positions) and different sizes can be evaluated for errors. The data extraction module of the scattering signal is optimized based on the error evaluation results to obtain a scattering information database.

[0097] In the embodiment of the present application, the target scatterer size is the size of the scatterer placed in the target closed environment, that is, the size of the scatterer that generates the corresponding jet in the target closed environment.

[0098] In the embodiment of the present application, the scattering information includes: scattering intensity.

[0099] In an embodiment of the present application, the scattering information and the target scatterer size corresponding to the position are matched from a pre-built scattering information database, including:

[0100] From the pre-built scattering information database, match the target scatterer size corresponding to the scattering intensity and position.

[0101] In one embodiment of the present application, Figure 2 As shown, the method for measuring the gas-liquid interface of a liquid jet in a closed environment of the present application comprises the following steps:

[0102] First, when no scatterer is provided in the closed combustion chamber, an ultrasonic generator is used to emit ultrasonic waves, and multiple ultrasonic detectors are used to receive ultrasonic signals to obtain a reference ultrasonic signal, such as Figure 3 as shown; Figure 4 As shown, an ultrasonic generator and multiple ultrasonic detectors are arranged in a circular ring in a closed combustion chamber. Figure 4 Among them, M1 to M7 are all ultrasonic detectors; ultrasonic generator is used to emit ultrasonic waves, and multiple ultrasonic detectors are used to receive target ultrasonic signals, such as Figure 5 As shown, the target ultrasonic signal includes: an original signal emitted by an ultrasonic generator, a scattered signal, and a signal reflected multiple times by the inner wall of the target closed environment.

[0103] Secondly, according to Figure 6 The process shown in the figure is to perform window processing on the reference ultrasonic signal and the target ultrasonic signal respectively, determine the signal start time, and use the ultrasonic emission time as the zero point to unify the zero point of the reference ultrasonic signal and the target ultrasonic signal; subtract the target ultrasonic signal after zero point unification from the reference ultrasonic signal to obtain the scattered signal. The result is shown in Figure 7 As shown, the waveforms of scattered signals extracted from target ultrasonic signals received by ultrasonic detectors at different positions are consistent (this is because the circular layout results in the same relative position of each ultrasonic detector and ultrasonic generator).

[0104] Finally, the error estimation of the scattered signals obtained by different receivers is performed, and the results are as follows: Figure 8 As shown in the figure; the envelope extraction result of the obtained scattered signal is shown in the attached figure. Fig. 9 As shown, for the first scattered wave packet, its wave packet envelope is obtained by local Hilbert transform, and the scattered wave packet is further envelope integrated, and its integral value is used as the wave packet energy of this wave packet, and the scattering intensity of the scattered wave packet is determined based on this wave packet energy.

[0105] In one embodiment of the present application, a method for constructing a scattering information database includes:

[0106] By performing ultrasonic measurements on scatterers with different fixed diameters in a closed combustion chamber, the relationship between the scatterer size and the scattered wave intensity at each measurement position is obtained. A set of typical measurement results is shown in the attached figure. Fig.10 As shown. Fig.10 It can be seen that for certain measurement positions, within a certain range of scatterer diameters, the scatterer diameter and the relative scattered sound pressure are linearly related. The frequency of the pulse scattered wave used at this time is 50-70kHz, and this frequency can be adjusted based on the object to be measured so that the scatterer diameter and the relative scattered sound pressure are linearly related. Further, the above-mentioned measurement objects are repeated to construct a database between scatterer sizes and scattering intensities at different frequencies and measurement positions, providing a basis for jet measurement.

[0107] The technical effects of this application are further explained below in conjunction with specific experiments.

[0108] In this experiment, according to the Figure 2 The jet in the closed combustion chamber was measured synchronously using an optical measurement method and an ultrasonic measurement method (i.e., a method for measuring the gas-liquid interface of a liquid jet in a closed environment provided in an embodiment of the present application); the scattering wave was extracted from the ultrasonic measurement data, and the jet diameter was inverted in combination with the scattering information database to obtain the corresponding scattering intensity; the specific results are shown in the attached Fig.11 . Fig.11 The vertical axis is the diameter information of the jet, the measured ultrasonic scattering intensity is the amplitude information, and the scattering information database establishes the relationship between the amplitude and the scatterer diameter ( Fig.10 ), combined with the amplitude of the jet (variable scatterer) and the database, the inversion of the scatterer diameter information can be realized, and then the diameter information of the scatterer can be obtained based on the scattering signal obtained by ultrasonic measurement. Fig.11 The final ultrasonic measurement results are compared with the optical measurement results. The two measurement methods are performed simultaneously. Fig.11 The c in the figure represents the error of the ultrasonic measurement result relative to the camera measurement result at each time point, which is obtained as abs (ultrasonic measurement diameter - camera measurement diameter) / camera measurement diameter.

[0109] from Fig.11 It can be seen that in the time domain and frequency domain, the results measured by the two measurement methods are almost the same, with an average error of only 0.07 mm, an average relative error of only 3.45%, and a time resolution of ultrasonic measurement greater than 1 kHz. This proves that the measurement method for the gas-liquid interface of a liquid jet in a closed environment provided in the embodiment of the present application can be applied to the measurement of the gas-liquid interface of a jet in a gas closed environment.

[0110] The method for measuring the gas-liquid interface of a liquid jet in a closed environment provided in the embodiment of the present application can be applied to measuring the gas-liquid interface of a liquid jet in a closed environment, such as the gas-liquid interface of a jet, droplets or spray field in a rocket engine combustion chamber, the remaining oil volume and liquid level distribution in a closed tanker truck, and there is no need to open an optical window. Only a scattering information database, the position of an ultrasonic detector in a closed environment and a previously measured reference signal are required to accurately obtain the size of the scatterer.

[0111] Corresponding to the above method, the embodiment of the present application also provides a device for measuring the gas-liquid interface of a liquid jet in a closed environment, such as Fig.12 As shown, the measuring device of the gas-liquid interface of the liquid jet in the closed environment includes:

[0112] The acquisition unit 1210 is used to acquire the position of the ultrasonic detector in the target closed environment and the reference ultrasonic signal and the target ultrasonic signal detected by the ultrasonic detector in the closed environment; wherein the reference ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector in the target closed environment when there is no jet in the first preset time period; and the target ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector in the target closed environment when there is a jet in the second preset time period;

[0113] A determination unit 1220, configured to obtain a scattered signal and corresponding scattered information based on the reference ultrasonic signal and the target ultrasonic signal;

[0114] The matching unit 1230 is used to match the target scatterer size corresponding to the scattering information and position from a pre-constructed scattering information database; wherein the target scatterer size is the size of the scatterer that generates the jet; the scattering information database includes: different scattering information and different positions and corresponding scatterer sizes.

[0115] The functions of each functional unit of the device for measuring the gas-liquid interface of a liquid jet in a closed environment provided in the above-mentioned embodiments of the present application can be achieved through the above-mentioned method steps. Therefore, the specific working process and beneficial effects of each unit in the device for measuring the gas-liquid interface of a liquid jet in a closed environment provided in the embodiments of the present application will not be repeated here.

[0116] The present application also provides an electronic device, such as Fig.13 As shown, it includes a processor 1310 , a communication interface 1320 , a memory 1330 and a communication bus 1340 , wherein the processor 1310 , the communication interface 1320 , and the memory 1330 communicate with each other via the communication bus 1340 .

[0117] Memory 1330, used for storing computer programs;

[0118] The processor 1310 is used to implement the following steps when executing the program stored in the memory 1330:

[0119] Acquire the position of the ultrasonic detector in the target enclosed environment and the reference ultrasonic signal and the target ultrasonic signal detected by the ultrasonic detector in the enclosed environment; wherein the reference ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector in the target enclosed environment when there is no jet in the first preset time period; and the target ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector in the target enclosed environment when there is a jet in the second preset time period;

[0120] Based on the reference ultrasonic signal and the target ultrasonic signal, a scattered signal and corresponding scattering information are obtained;

[0121] The target scatterer size corresponding to the scattering information and position is matched from a pre-constructed scattering information database; wherein the target scatterer size is the size of the scatterer that generates the jet; the scattering information database includes: different scattering information and different positions and corresponding scatterer sizes.

[0122] The communication bus mentioned above can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The communication bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one thick line is used in the figure, but it does not mean that there is only one bus or one type of bus.

[0123] The communication interface is used for communication between the above electronic device and other devices.

[0124] The memory may include a random access memory (RAM) or a non-volatile memory (NVM), such as at least one disk memory. Optionally, the memory may also be at least one storage device located away from the aforementioned processor.

[0125] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0126] The implementation methods and beneficial effects of the components of the electronic device in the above embodiments to solve the problems can be found in Figure 1 The various steps in the illustrated embodiment are implemented, therefore, the specific working process and beneficial effects of the electronic device provided by the embodiment of the present application are not repeated here.

[0127] In another embodiment provided in the present application, a computer-readable storage medium is also provided, which stores instructions. When the computer-readable storage medium is run on a computer, the computer executes the method for measuring the gas-liquid interface of a liquid jet in a closed environment in any of the above embodiments.

[0128] In another embodiment provided in the present application, a computer program product including instructions is also provided, which, when executed on a computer, enables the computer to execute the method for measuring the gas-liquid interface of a liquid jet in a closed environment in any of the above embodiments.

[0129] Those skilled in the art will appreciate that the embodiments in the present application can be provided as methods, systems, or computer program products. Therefore, the embodiments in the present application can be in the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the embodiments in the present application can be in the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0130] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0131] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0132] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0133] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present application.

[0134] Obviously, those skilled in the art can make various changes and modifications to the embodiments in the present application without departing from the spirit and scope of the embodiments in the present application. Thus, if these modifications and variations of the embodiments in the present application fall within the scope of the claims and their equivalents in the embodiments of the present application, the embodiments of the present application are also intended to include these modifications and variations.

Claims

1. A method for measuring the gas-liquid interface of a liquid jet in a closed environment, characterized in that: The method comprises: Acquire the position of the ultrasonic detector in the target closed environment and the reference ultrasonic signal and target ultrasonic signal detected by the ultrasonic detector in the closed environment; wherein the reference ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector when there is no jet in the target closed environment within a first preset time period; the target ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector when there is a jet in the target closed environment within a second preset time period; any target ultrasonic signal and any reference ultrasonic signal correspond to a collection time; the starting time of the first preset time period and the second preset time are both the time when ultrasonic waves are started to be emitted in the target closed environment; Performing signal window processing on the reference ultrasonic signal and the target ultrasonic signal to obtain a processed target ultrasonic signal and a processed reference ultrasonic signal; Taking the time of transmitting the ultrasonic wave in the target closed environment as the zero point, aligning the acquisition time of the processed target ultrasonic wave signal and the processed reference ultrasonic wave signal; Acquire a scattered signal and corresponding scattering information based on the reference ultrasonic signal and the target ultrasonic signal after the acquisition time alignment; The target scatterer size corresponding to the scattering information and the position is matched from a pre-constructed scattering information database; wherein the target scatterer size is the size of the scatterer that generates the jet; the scattering information database includes: different scattering information and different positions and corresponding scatterer sizes.

2. The method according to claim 1, characterized in that Acquiring a scattered signal and corresponding scattering information based on the reference ultrasonic signal and the target ultrasonic signal includes: For any acquisition time, a target voltage value and a reference voltage value are obtained; wherein the target voltage value is a voltage value corresponding to the target ultrasonic signal corresponding to the acquisition time; and the reference voltage value is a voltage value corresponding to the reference ultrasonic signal corresponding to the acquisition time; Subtracting the reference voltage value from the target voltage value to obtain a scattering signal corresponding to the acquisition time; Scattering information is extracted from the scattering signal to obtain scattering information corresponding to the acquisition time.

3. The method according to claim 2, characterized in that Extracting scattering information from the scattering signal to obtain scattering information corresponding to the acquisition time includes: Extracting a plurality of pulse scattered wave packets from the scattered signal; The first pulse scattering wave packet extracted is used as the target pulse scattering wave packet; Performing a Hilbert transform on the target pulse scattering wave packet to obtain an envelope of the target pulse scattering wave packet; Based on the envelope, scattering information corresponding to the acquisition time is determined.

4. The method according to claim 1, characterized in that The scattering information includes: scattering intensity; Matching the scattering information and the target scatterer size corresponding to the position from a pre-built scattering information database includes: The scattering intensity and the target scatterer size corresponding to the position are matched from a pre-constructed scattering information database.

5. A device for measuring the gas-liquid interface of a liquid jet in a closed environment, characterized in that: The device comprises: An acquisition unit is used to acquire the position of the ultrasonic detector in the target closed environment and the reference ultrasonic signal and the target ultrasonic signal detected by the ultrasonic detector in the closed environment; wherein the reference ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector when there is no jet in the target closed environment within a first preset time period; the target ultrasonic signal is an ultrasonic signal collected by the ultrasonic detector when there is a jet in the target closed environment within a second preset time period; any target ultrasonic signal and any reference ultrasonic signal correspond to a collection time; the starting time of the first preset time period and the second preset time are both the time when ultrasonic waves are started to be emitted in the target closed environment; A processing unit is used to perform signal window processing on the reference ultrasonic signal and the target ultrasonic signal to obtain a processed target ultrasonic signal and a processed reference ultrasonic signal; taking the time of transmitting the ultrasonic wave in the target closed environment as the zero point, and aligning the acquisition time of the processed target ultrasonic signal and the processed reference ultrasonic signal; A determination unit, configured to acquire a scattered signal and corresponding scattering information based on the reference ultrasonic signal and the target ultrasonic signal after the acquisition time is aligned; A matching unit is used to match the scattering information and the target scatterer size corresponding to the position from a pre-constructed scattering information database; wherein the target scatterer size is the size of the scatterer that generates the jet; the scattering information database includes: different scattering information and different positions and corresponding scatterer sizes.

6. An electronic device, characterized in that: The electronic device comprises a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus; Memory, used to store computer programs; A processor, for implementing any of the methods described in claims 1-4 when executing a program stored in a memory.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 4 is implemented.

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