Device for monitoring combustion process in real time

Abstract

The invention provides a device for monitoring a combustion process in real time, and belongs to the technical field of combustion process monitoring and control. The device comprises a multispectral light source module, an optical detection module, a data processing module and a control module. The multispectral light source module can emit multispectral signals covering ultraviolet, visible and infrared bands, and multiple paths of light beams are generated through light beam shaping, frequency doubling, optical parametric oscillation and the like and are incident to a combustion area. The data processing module performs feature extraction, mode recognition and trend prediction on the signals, and recognizes parameters such as flame state, temperature, gas concentration, combustion efficiency and pollutant emission. The control module dynamically adjusts operation parameters of the combustor according to the analysis result, and closed-loop control is achieved. Through multi-band spectrum joint detection and intelligent algorithm analysis, the defect that single-band detection is prone to interference is overcome, and high-sensitivity, multi-dimensional and real-time monitoring and intelligent control over the combustion process are achieved.

Description

Technical Field

[0001] This disclosure relates to the field of combustion process monitoring and control technology, and more specifically, to a device for real-time monitoring of the combustion process. Background Technology

[0002] With the development of industrial boilers, gas turbines, internal combustion engines, incinerators, and other equipment, the stability, efficiency, and pollutant emission levels of the combustion process directly affect the safety, economy, and environmental friendliness of equipment operation. The combustion process is the core link in energy conversion, and its efficiency and stability directly affect energy utilization, equipment lifespan, and environmental pollutant emission levels. Traditional combustion monitoring methods mainly rely on thermocouples, pressure sensors, or single-band optical sensors. These methods suffer from slow response, susceptibility to environmental interference, and limited information dimensions, making it difficult to meet the demands of modern industry for high-precision, real-time, and intelligent control of the combustion process.

[0003] In recent years, with the development of optical sensing and spectral analysis technologies, the application of spectral technology in combustion monitoring has gradually attracted attention. By analyzing the characteristics of light radiation generated during combustion, information such as combustion temperature, component concentration, and flame stability can be obtained non-contactly and in real time. However, existing technologies still have the following shortcomings: single-band spectral detection is easily affected by background light, smoke, particulate matter, etc., leading to a decrease in monitoring accuracy. Furthermore, relying solely on spectral analysis or interferometry fails to fully utilize the complementarity of multi-band information, resulting in insufficient monitoring accuracy and robustness. Summary of the Invention

[0004] The purpose of this disclosure is to provide a device for real-time monitoring of the combustion process, which can solve the technical problem of low accuracy in single-band spectral monitoring. The specific solution is as follows:

[0005] According to specific embodiments of this disclosure, this disclosure provides an apparatus for real-time monitoring of the combustion process, characterized in that it includes:

[0006] A multispectral light source module is used to generate and emit multispectral signals covering ultraviolet, visible, and infrared light to the combustion zone; it includes an optical power control optical path, a beam shaping optical path, an optical parametric oscillation optical path, and a multispectral output optical path arranged sequentially along the optical path direction; the optical power control optical path is used to control the overall beam intensity in the light source and optical path; the beam shaping optical path is used to generate a vortex beam with a preset polarization direction; the optical parametric oscillation optical path is used to generate near-infrared beams and mid-infrared beams; and the multispectral output optical path is used to output visible beams, ultraviolet beams, and infrared beams.

[0007] An optical detection module is used to acquire multispectral light intensity signals passing through the combustion zone;

[0008] The data processing module is used to perform spectral feature data analysis on the received multispectral light intensity signal, obtain the combustion characteristic parameters of the flame in the combustion zone, and predict the combustion trend; the combustion characteristic parameters of the flame include at least: flame characteristic parameters, light intensity distribution, combustion temperature, temperature change, combustion state, gas concentration, combustion efficiency, pollutant emission concentration, and combustion zone pressure;

[0009] The control module is used to generate control signals based on the analysis results of the data processing module, adjust the combustion process, and achieve closed-loop control.

[0010] Preferably, the optical power control optical path includes a pump source, a first focusing lens, a first half-wave plate, a Faraday rotator, a first polarizing beam splitter, and a first light absorber arranged sequentially along the optical path direction;

[0011] The beam shaping optical path includes a second half-wave plate, a second focusing lens, a first nonlinear crystal, a first dichroic mirror, a second light absorber, a first total reflection mirror, a third focusing lens, a spiral phase plate, and a third half-wave plate arranged sequentially along the optical path direction.

[0012] The optical parametric oscillation optical path includes an input mirror, a second nonlinear crystal, and an output mirror arranged sequentially along the optical path direction;

[0013] The multispectral output optical path includes a visible spectrum output optical path, an ultraviolet spectrum output optical path, and an infrared spectrum output optical path.

[0014] Preferably, the visible spectrum output optical path includes a second dichroic mirror, a second total reflection mirror, a fourth half-wave plate, a third nonlinear crystal, a fifth dichroic mirror, and a third total reflection mirror arranged sequentially along the optical path direction;

[0015] The ultraviolet spectral output optical path includes a third dichroic mirror, a fourth total reflection mirror, a sixth dichroic mirror, a fourth nonlinear crystal, a seventh dichroic mirror, and a fifth total reflection mirror arranged sequentially along the optical path direction;

[0016] The infrared spectral output optical path includes a sixth total reflection mirror, a seventh total reflection mirror, a tenth total reflection mirror, an eighth total reflection mirror, and a ninth total reflection mirror arranged sequentially along the optical path direction.

[0017] Preferably, the optical detection module includes:

[0018] The detector array includes an ultraviolet light detector, a visible light detector, and an infrared light detector, which respectively detect and acquire multispectral signals in the corresponding bands of the combustion area;

[0019] The optical filtering noise suppression unit filters and reduces noise in the multispectral signal to reduce interference from ambient light and background light in the combustion area.

[0020] Preferably, the data processing module includes:

[0021] A multi-channel signal processing unit is used to synchronously process multispectral light intensity signals, perform photoelectric conversion, and output them to the algorithm recognition unit.

[0022] The algorithm recognition unit is used to identify different spectral feature signals, extract the combustion feature parameters of the flame from ultraviolet radiation spectral feature signals, infrared radiation spectral feature signals, and visible light radiation spectral feature signals, identify the combustion feature parameters of the flame through a pattern recognition algorithm, and match them with a pre-established combustion state model to determine whether the current combustion state of the combustion zone is in a normal or abnormal state.

[0023] An adaptive analysis unit is used to compare and analyze the combustion state with a pre-established historical database of combustion zones to predict trend changes during the combustion process. The adaptive analysis unit estimates the combustion characteristic parameters of the flame in real time through Kalman filtering, dynamically adjusts the operating parameters of the combustion zone based on the real-time estimates through an adaptive control algorithm, and transmits the analysis results of the operating parameter data to the control module.

[0024] Preferably, the pattern recognition algorithm is trained using a support vector machine or a neural network to identify the combustion characteristic parameters of the flame.

[0025] Preferably, the multi-channel signal processing unit synchronously processes multispectral light intensity signals by: eliminating interference signals from non-target bands through optical filters and fusing data from different bands to improve the monitoring accuracy of combustion status.

[0026] Preferably, the control module includes:

[0027] The closed-loop control unit is used to dynamically adjust the working parameters of the combustion zone based on the analysis results of the data processing module, thereby achieving closed-loop control.

[0028] The safety protection unit is used to issue an alarm signal or trigger an emergency shutdown function when the data processing module detects an abnormal combustion result.

[0029] Preferably, the combustion zone includes:

[0030] The turbine intake unit is located on the side of the burner and has inclined holes in the same direction as the turbine blades to improve intake efficiency;

[0031] The cooling unit, located outside the combustion chamber, includes a tightly wound metal tube for introducing coolant or cooling gas to achieve uniform cooling.

[0032] Preferably, it also includes a display and storage module for displaying the combustion characteristic parameters in real time and saving the monitoring data.

[0033] Compared with the prior art, the above-described solutions of this disclosure have at least the following beneficial effects:

[0034] 1. The device disclosed herein is for real-time monitoring of the combustion process. It simultaneously detects and collects multispectral signals of ultraviolet light, visible light and infrared light, covering the presence, structure and thermodynamic characteristics of flames. It has a small detection blind zone and can realize multispectral joint monitoring, multi-dimensional detection of combustion status, and comprehensive understanding of combustion process and combustion trend. It can significantly improve the accuracy and practicality of combustion monitoring.

[0035] 2. The device for real-time monitoring of the combustion process disclosed herein can effectively suppress interference from smoke, vibration, and background light by using both optical filtering and Kalman filtering for noise reduction, thereby improving the accuracy of monitoring.

[0036] 3. The technical solution of the multispectral light source module in the device for real-time monitoring of the combustion process disclosed herein has a compact optical structure design. After frequency doubling, optical parametric oscillation and summing of a single-band pump source, visible light, ultraviolet light and infrared light output can be realized simultaneously, simplifying and shortening the optical path. Attached Figure Description

[0037] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0038] Figure 1 This is a schematic diagram of a multispectral light source module provided in an embodiment of the present invention. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this disclosure clearer, the disclosure will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0040] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the article or device that includes said element.

[0041] The following is in conjunction with the appendix Figure 1 Detailed description of optional embodiments of the present invention.

[0042] Example 1

[0043] According to a specific embodiment of the present invention, the present invention provides a device for real-time monitoring of the combustion process, comprising the following modules: a multispectral light source module, an optical detection module, a data processing module, and a control module.

[0044] A multispectral light source module is used to generate and emit multispectral signals covering ultraviolet, visible, and infrared light to the combustion zone 36. It includes a power control optical path, a beam shaping optical path, a parametric oscillation optical path, and a multispectral output optical path arranged sequentially along the optical path. The power control optical path provides control over the overall beam intensity in the light source and optical path. The beam shaping optical path generates a vortex beam with a preset polarization direction. The parametric oscillation optical path generates near-infrared and mid-infrared beams. The multispectral output optical path outputs visible, ultraviolet, and infrared beams. An optical detection module is used to acquire multispectral light intensity signals passing through the combustion zone 36. A data processing module performs spectral characteristic data analysis on the received multispectral light intensity signals to obtain combustion characteristic parameters of the flame within the combustion zone 36 and predict combustion trends. The combustion characteristic parameters of the flame include at least: flame characteristic parameters, light intensity distribution, combustion temperature, temperature change, combustion state, gas concentration, combustion efficiency, pollutant emission concentration, and pressure in the combustion zone 36. The control module is used to generate control signals based on the analysis results of the data processing module, adjust the combustion process, and achieve closed-loop control.

[0045] In this embodiment of the invention, the multispectral light source module generates and emits multispectral signals covering ultraviolet, visible, and infrared light to the combustion zone 36, enabling full-range monitoring of the combustion process. Specifically, the ultraviolet spectral signal can monitor the presence of free radicals and flames in the combustion zone 36. Using laser-induced fluorescence (LIF) technology, free radicals (such as OH, CH, CN) or molecules in combustion are excited by an ultraviolet laser, and their fluorescence signals are measured. Ultraviolet spectroscopy can detect the absorption or fluorescence characteristics of pollutants such as NO and NO2, and the ultraviolet spectral signal is less affected by the absorption of smoke, CO2, etc., making it suitable for complex combustion environments. The visible spectral signal can monitor the flame structure and state in the combustion zone 36, using visible light to capture the turbulent structure and velocity field of the flame. The infrared radiation intensity of the infrared spectral signal is directly related to the flame temperature, can penetrate smoke, and detect the absorption characteristics of gases such as CO2 and H2O. Infrared lasers, such as near-infrared or mid-infrared, are used to measure the absorption spectra of molecules such as H2O and CO2 using TDLAS technology to estimate the combustion temperature. The multispectral light source module uses a combination of multiple bands: ultraviolet spectral signals to detect the presence of flames, visible light spectral signals to analyze the structure, and infrared spectral signals to measure temperature and gas. These three signals correspond to the presence, structure, and thermodynamic characteristics of flames through free radical radiation, thermal radiation, and gas absorption mechanisms, respectively. The three signals work together to achieve high-precision, all-weather monitoring of the combustion zone 36.

[0046] In this embodiment of the invention, the optical detection module includes: a detector array 37 comprising an ultraviolet detector, a visible light detector, and an infrared detector, which respectively detect and acquire multispectral signals in the corresponding bands of the combustion zone 36. An optical filtering and noise suppression unit filters and reduces noise in the multispectral signals to minimize interference from ambient light and background light in the combustion zone 36.

[0047] In this embodiment of the invention, the data processing module includes: a multi-channel signal processing unit, used to synchronously process multispectral light intensity signals, perform photoelectric conversion, and output the results to the algorithm recognition unit. The multi-channel signal processing unit uses optical filters to eliminate interference signals from non-target bands and fuses data from different bands to improve the signal-to-noise ratio, thereby enhancing the monitoring accuracy of the combustion state. The algorithm recognition unit is used to identify different spectral feature signals, extracting combustion feature parameters of the flame from ultraviolet radiation spectral feature signals, infrared radiation spectral feature signals, and visible light radiation spectral feature signals. It identifies the combustion feature parameters of the flame using a pattern recognition algorithm and matches them with a pre-established combustion state model to determine whether the current combustion state of combustion zone 36 is normal or abnormal. An adaptive analysis unit is used to compare and analyze the combustion state with a pre-established historical database of combustion zone 36 to predict trend changes during the combustion process. The adaptive analysis unit estimates the combustion feature parameters of the flame in real time using Kalman filtering, dynamically adjusts the operating parameters of combustion zone 36 based on the real-time estimates using an adaptive control algorithm, and transmits the analysis results of the operating parameter data to the control module. In this embodiment of the invention, the pattern recognition algorithm is trained using a support vector machine or a neural network to identify the combustion characteristic parameters of the flame.

[0048] In this embodiment of the invention, a preferred solution is provided: when the number of samples detected during the combustion process is moderate, the pattern recognition algorithm uses a support vector machine to distinguish different categories of combustion states by finding the optimal hyperplane. For example, when combustion monitoring is required for flame state classification, such as high-efficiency combustion, normal combustion, low-efficiency combustion, and unstable flame, the following applies: During normal combustion, the intensity of the ultraviolet spectral signal is strong and stable, indicating that the combustion temperature is moderate and the fuel is fully combusted. During low-efficiency combustion, the intensity of the ultraviolet spectral signal is low and fluctuates, indicating that the fuel is not completely combusted and there are unburned substances. During unstable flame, the ultraviolet spectral signal and frequency are unstable, which may mean the risk of flame fluctuation or flameout.

[0049] In this embodiment of the invention, a preferred solution is provided. When the number of samples detected during the combustion process is large and abundant, and the requirement for high recognition accuracy is high, the pattern recognition algorithm uses a convolutional neural network (CNN) of deep neural network to automatically extract features from the acquired multispectral images or signals to accurately classify the combustion state. The ultraviolet light signal of the flame exhibits different light intensity spectral distributions under normal combustion and incomplete combustion conditions. The pattern recognition algorithm can classify the combustion state into categories such as "normal combustion," "inefficient combustion," or "unstable flame" based on these characteristics. During normal combustion, the intensity of the ultraviolet light signal is strong and stable, indicating a moderate combustion temperature and complete fuel combustion. During inefficient combustion, the intensity of the ultraviolet light signal is low and fluctuates, indicating incomplete fuel combustion and the presence of unburned substances. When the flame is unstable, the signal intensity and frequency are unstable, which may indicate a risk of flame fluctuation or flameout.

[0050] In this embodiment of the invention, a preferred solution is provided. The adaptive analysis unit compares the real-time monitoring data provided by the algorithm identification unit with historical data. The Kalman filter algorithm estimates the changes in dynamic parameters such as temperature and pressure during the combustion process in real time, predicting the trend changes in the combustion state. The Kalman filter algorithm can effectively suppress sensor noise, improve the smoothness and accuracy of parameter estimation, and provide highly reliable feedback input for the control module. The adaptive analysis unit, through an adaptive control adjustment algorithm, adaptively adjusts the burner's operating parameters based on the deviation between the trend changes in the combustion state and the pre-established historical database of combustion zone 36. If abnormal temperature fluctuations occur during combustion, a comparison of the real-time signal estimation results with the pre-established historical database of combustion zone 36 reveals that the current combustion efficiency is low and may lead to increased pollutant emissions. The adaptive analysis algorithm automatically adjusts the oxygen supply in combustion zone 36 through the control system, increasing the oxygen concentration, thereby increasing the combustion temperature, reducing incomplete combustion, and lowering pollutant emissions. As the temperature rises, the combustion process becomes stable, the flame color becomes more uniform, and the ultraviolet light signal becomes stronger and more stable; the optimized combustion parameters match the historical best combustion state, improving combustion efficiency and reducing pollutant concentration. When an abnormal combustion state is detected, such as an unstable flame or excessively high temperature, the algorithm can automatically issue an alarm or adjust the combustion parameters through the control system to ensure the safety and efficiency of the combustion process.

[0051] In this embodiment of the invention, the control module generates control signals based on the analysis results of the data processing module, including a closed-loop control unit and a safety protection unit. The closed-loop control unit dynamically adjusts parameters such as fuel flow rate, air ratio, and oxygen concentration based on the analysis results output by the data processing module. It adjusts and optimizes various parameters of the burner based on the results, and regulates the output of fuel vapor from the fuel storage pressure tank in real time via a pressure valve. After fuel is output, it enters the burner in combustion zone 36. The safety protection unit is used to issue an alarm signal or trigger an emergency shutdown when it detects combustion abnormalities in the data processing module's analysis results, such as flameout, overheating, or abnormal pressure, ensuring the safe operation of the system.

[0052] In this embodiment of the invention, a preferred solution is provided: the device for real-time monitoring of the combustion process further includes a display and storage module for displaying combustion characteristic parameters in real time and saving monitoring data. Depending on the actual use, the display and storage module may also be equipped with a remote interaction unit or connected to the safety protection unit in the control module to form an alarm linkage. This embodiment of the invention does not limit this and can be selected according to the actual situation. The display and storage module realizes real-time visualization and long-term archiving of combustion parameters, significantly improving the intelligence level and engineering practicality of the device for real-time monitoring of the combustion process.

[0053] In this embodiment of the invention, a preferred solution is provided: the combustion zone 36 of the device for real-time monitoring of the combustion process includes a turbine intake unit and a cooling unit. The turbine intake unit incorporates inclined holes on the side of the burner, aligned with the direction of the turbine blades, to increase intake efficiency. During combustion, the high-temperature, high-pressure gas generated in the combustion zone 36 drives the turbine, generating positive feedback to further improve combustion efficiency. The cooling unit is located outside the combustion chamber and consists of tightly wound copper tubing filled with coolant or cooling gas, achieving uniform cooling of the combustion chamber and protecting the burner for stable operation at high temperatures.

[0054] The technical solution for real-time monitoring of the combustion process provided in this embodiment of the invention utilizes multispectral signals from ultraviolet, visible, and infrared light for simultaneous detection and acquisition, covering flame presence, structure, and thermodynamic characteristics with a small detection blind zone. The technical solution provided by this invention employs dual noise reduction through optical filtering and Kalman filtering, effectively suppressing interference from smoke, vibration, and background light. It is suitable for applications such as combustion status monitoring and optimization in industrial boilers, exhaust emission control and combustion performance optimization in internal combustion engines, and flame characteristic monitoring in gas turbine combustion chambers. Furthermore, the technical solution provided by this invention uses an adaptive control unit to adjust the air-fuel ratio and fuel flow rate in real time, effectively improving combustion efficiency and reducing pollutant emissions.

[0055] Example 2

[0056] As an optional implementation, this disclosure also provides an embodiment of the multispectral light source module as described above. The interpretation of the same names is the same as that of the above embodiments, and the same technical effects are achieved. Therefore, it will not be described again here.

[0057] In this embodiment of the invention, the multispectral light source module is used to generate and emit multispectral signals covering ultraviolet, visible, and infrared light to the combustion zone 36; it includes an optical power control optical path, a beam shaping optical path, an optical parametric oscillation optical path, and a multispectral output optical path arranged sequentially along the optical path direction; the optical power control optical path is used to provide control over the overall beam intensity in the light source and the optical path; the beam shaping optical path is used to generate a vortex beam with a preset polarization direction; the optical parametric oscillation optical path is used to generate a near-infrared beam and a mid-infrared beam; and the multispectral output optical path is used to output a visible beam, an ultraviolet beam, and an infrared beam.

[0058] like Figure 1 As shown, the optical power control optical path includes a pump source 1, a first focusing lens 2, a first half-wave plate 3, a Faraday rotator 4, a first polarizing beam splitter 6, and a first light absorber 5 arranged sequentially along the optical path direction.

[0059] In this embodiment of the invention, the pump source 1 is an Nd:YAG Q-switched solid-state laser with a center wavelength of 1064 nm for the output laser beam. The pump beam emitted from pump source 1 is focused by the first focusing lens 2 and transmitted sequentially to the first half-wave plate 3. After passing through the first half-wave plate 3, it is sequentially incident on the Faraday rotator 4 and the first polarizing beam splitter 6. The polarized beam reflected by the first polarizing beam splitter 6 is absorbed by the first light absorber 5, and the transmitted polarized beam is incident on the subsequent optical path. The Faraday rotator 4 isolates the reflected light, preventing damage to pump source 1. By adjusting the polarization direction of the incident beam on the first half-wave plate 3, the ratio of transmitted to reflected beams in the first polarizing beam splitter 6 is matched, thereby achieving adjustment and control of the total power of the laser beam in the subsequent optical path.

[0060] The beam shaping optical path includes a second half-wave plate 7, a second focusing lens 8, a first nonlinear crystal 9, a first dichroic mirror 10, a second light absorber, a first total reflection mirror 12, a third focusing lens 13, a spiral phase plate 14, and a third half-wave plate 15 arranged sequentially along the optical path direction.

[0061] In this embodiment of the invention, the polarized beam transmitted through the first polarizing beam splitter 6 is incident on the second half-wave plate 7. After the polarization direction of the beam is adjusted by the second half-wave plate 7, it is incident on the second focusing lens 8 for focusing. The focused beam is incident on the first nonlinear crystal 9, which doubles the frequency to a wavelength of 532nm. The doubled beam is incident on the first dichroic mirror 10, which splits the pump beam and the doubled beam. The pump beam is absorbed by the second light absorber 11, and the doubled beam is reflected by the first total reflection mirror 12 to the third focusing lens 13 for focusing. The focused beam is incident on the spiral phase plate 14 and shaped into a vortex beam before being incident on the third half-wave plate 15. After the polarization direction of the beam is adjusted by the third half-wave plate 15, it is incident on the subsequent optical path.

[0062] The optical parametric oscillation optical path includes an input mirror 16, a second nonlinear crystal 17, and an output mirror 18 arranged sequentially along the optical path direction.

[0063] In this embodiment of the invention, the beam whose polarization direction is adjusted by the third half-wave plate 15 is sequentially incident on the input mirror 16, the second nonlinear crystal 17, and the output mirror 18. The input mirror 16 transmits the frequency-doubled beam after high transmission, ensuring that the frequency-doubled beam enters the second nonlinear crystal 17 efficiently; the highly reflective signal beam forms resonant feedback. The signal beam, after undergoing optical parametric conversion by the second nonlinear crystal 17, is incident on the output mirror 18. The output mirror 18 reflects part of the signal beam, allowing part of the signal beam to be output while maintaining intracavity oscillation; the fully transparent idler beam outputs mid-infrared light. The beam generated by the optical parametric oscillation optical path consists of a near-infrared signal beam and a mid-infrared idler beam. At this time, the beam generated in the optical path includes near-infrared, mid-infrared, and visible light. That is, the output mirror 18 outputs a frequency-doubled beam with a wavelength of 532nm, a signal beam of 690-1050nm, and an idler beam of 1800-2150nm.

[0064] The multispectral output optical path includes a visible spectrum output optical path, an ultraviolet spectrum output optical path, and an infrared spectrum output optical path. The visible spectrum output optical path includes, along the optical path direction, a second dichroic mirror 19, a second total reflection mirror 24, a fourth half-wave plate 25, a third nonlinear crystal 26, a fourth dichroic mirror 27, and a third total reflection mirror 34, arranged sequentially. The ultraviolet spectrum output optical path includes, along the optical path direction, a third dichroic mirror 20, a fourth total reflection mirror 23, a fifth dichroic mirror 28, a fourth nonlinear crystal 29, a sixth dichroic mirror 30, and a fifth total reflection mirror 32, arranged sequentially. The infrared spectrum output optical path includes, along the optical path direction, a sixth total reflection mirror 31, a seventh total reflection mirror 33, a tenth reflection mirror 21, an eighth total reflection mirror 22, and a ninth total reflection mirror 35, arranged sequentially.

[0065] In this embodiment of the invention, near-infrared, mid-infrared, and visible light beams enter the second dichroic mirror 19, the third dichroic mirror 20, and the tenth reflecting mirror 21 for wavelength-selective reflection and transmission, achieving spatial separation and guiding them to subsequent processing optical paths. In the visible spectrum output optical path, the beam is incident on the second dichroic mirror 19, transmitting the near-infrared signal beam and the mid-infrared idler beam, reflecting the 532nm frequency-doubled beam. The transmitted beam is received by the second total reflection mirror 24 and reflected to the fourth half-wave plate 25. After the polarization state of the beam is changed by the fourth half-wave plate 25, it is incident on the third nonlinear crystal 26 for further frequency doubling, resulting in a fourth frequency-doubled beam with a wavelength of 266nm, thus extending the beam band in the optical path to the ultraviolet band. The beam is incident on the fourth dichroic mirror 27, which splits the frequency-doubled beam and the fourth frequency-doubled beam. The frequency-doubled beam after transmission and splitting is incident on the third total reflection mirror 34 and reflected to the combustion zone 36. That is, 532nm visible light is incident on the combustion zone 36.

[0066] In this embodiment of the invention, in the ultraviolet spectral output optical path, the light beam is incident on the third dichroic mirror 20, which transmits the near-infrared signal beam with wavelengths above 1050nm and reflects the beam with wavelengths below 1050nm. The reflected beam is received by the fourth total reflection mirror 23 and reflected to the fifth dichroic mirror 28. The fifth dichroic mirror 28 combines the signal beam with wavelengths below 1050nm and the fourth harmonic beam. The combined beam is incident on the fourth nonlinear crystal 29 for frequency summation, resulting in a tunable vortex beam in the vacuum ultraviolet band with a wavelength of 193nm. The vortex beam is incident on the sixth dichroic mirror 30, which transmits the ultraviolet beam and reflects beams of other wavelengths. The vacuum ultraviolet beam and the 266nm ultraviolet beam are reflected by the fifth total reflection mirror 32 to the combustion zone 36. This achieves the separation of multi-wavelength beams, facilitating their guidance to the combustion zone 36. In this embodiment of the invention, vortex beam shaping can reduce thermal damage and effectively protect the fourth nonlinear crystal 29.

[0067] In this embodiment of the invention, the infrared spectral output optical path includes a sixth total internal reflection mirror 31, a seventh total internal reflection mirror 33, a tenth total internal reflection mirror 21, an eighth total internal reflection mirror 22, and a ninth total internal reflection mirror 35. Near-infrared signal beams and idler beams with wavelengths above 1050 nm, transmitted through the third dichroic mirror 20, are incident on the tenth total internal reflection mirror 21. The tenth total internal reflection mirror 21 reflects the signal beams and idler beams, and the reflected near-infrared signal beams and mid-infrared idler beams are sequentially incident on the eighth total internal reflection mirror 22 and the ninth total internal reflection mirror 35, and then reflected to the combustion zone 36. Other wavelength beams, including near-infrared beams, separated by the sixth dichroic mirror 30, are reflected to the combustion zone 36 by the sixth total internal reflection mirror 31 and the seventh total internal reflection mirror 33.

[0068] The multispectral light source module provided in this invention features a compact optical structure. Through frequency doubling, optical parametric oscillation, and sum-frequency conversion of a single-band pump source 1, it simultaneously outputs visible, ultraviolet, and infrared light, simplifying and shortening the optical path. The technical solution provided by this invention offers continuous and adjustable optical power. The optical path design allows for stepless power adjustment from 0–20W, matching different fuels and combustion states, avoiding detector saturation or excessively weak spectral signals, and ensuring stable output power. The multispectral beam is simultaneously incident on the combustion zone 36, undergoing absorption, scattering, and excitation processes with free radicals, thermal radiation, and gas molecules in the flame, forming a more comprehensive spectrum with combustion characteristics. This enables multispectral joint monitoring, multi-dimensional detection of the combustion state, and a comprehensive understanding of the combustion process and trends, significantly improving the accuracy and practicality of combustion monitoring.

[0069] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems or apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.

[0070] The above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit it. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A device for real-time monitoring of the combustion process, characterized in that, include: A multispectral light source module is used to generate and emit multispectral signals covering ultraviolet, visible, and infrared light to the combustion zone; It includes an optical power control optical path, a beam shaping optical path, an optical parametric oscillation optical path, and a multispectral output optical path arranged sequentially along the optical path direction; The optical power control optical path is used to control the overall beam intensity in the light source and optical path; the beam shaping optical path is used to generate a vortex beam with a preset polarization direction; the optical parametric oscillation optical path is used to generate a near-infrared beam and a mid-infrared beam; and the multispectral output optical path is used to output a visible beam, an ultraviolet beam, and an infrared beam. An optical detection module is used to acquire multispectral light intensity signals passing through the combustion zone; The data processing module is used to perform spectral feature data analysis on the received multispectral light intensity signal, obtain the combustion feature parameters of the flame in the combustion zone, and predict the combustion trend. The control module is used to generate control signals based on the analysis results of the data processing module, adjust the combustion process, and achieve closed-loop control.

2. The apparatus for real-time monitoring of the combustion process according to claim 1, characterized in that, The optical power control optical path includes a pump source, a first focusing lens, a first half-wave plate, a Faraday rotator, a first polarizing beam splitter, and a first optical absorber arranged sequentially along the optical path direction; The beam shaping optical path includes a second half-wave plate, a second focusing lens, a first nonlinear crystal, a first dichroic mirror, a second light absorber, a first total reflection mirror, a third focusing lens, a spiral phase plate, and a third half-wave plate arranged sequentially along the optical path direction. The optical parametric oscillation optical path includes an input mirror, a second nonlinear crystal, and an output mirror arranged sequentially along the optical path direction; The multispectral output optical path includes a visible spectrum output optical path, an ultraviolet spectrum output optical path, and an infrared spectrum output optical path.

3. The apparatus for real-time monitoring of the combustion process according to claim 2, characterized in that, The visible spectrum output optical path includes a second dichroic mirror, a second total reflection mirror, a fourth half-wave plate, a third nonlinear crystal, a fifth dichroic mirror, and a third total reflection mirror arranged sequentially along the optical path direction; The ultraviolet spectral output optical path includes a third dichroic mirror, a fourth total reflection mirror, a sixth dichroic mirror, a fourth nonlinear crystal, a seventh dichroic mirror, and a fifth total reflection mirror arranged sequentially along the optical path direction; The infrared spectral output optical path includes a sixth total reflection mirror, a seventh total reflection mirror, a tenth total reflection mirror, an eighth total reflection mirror, and a ninth total reflection mirror arranged sequentially along the optical path direction.

4. The apparatus for real-time monitoring of the combustion process according to claim 3, characterized in that, The optical detection module includes: The detector array includes an ultraviolet light detector, a visible light detector, and an infrared light detector, which respectively detect and acquire multispectral signals in the corresponding bands of the combustion area; The optical filtering noise suppression unit filters and reduces noise in the multispectral signal to reduce interference from ambient light and background light in the combustion area.

5. The apparatus for real-time monitoring of the combustion process according to claim 4, characterized in that, The data processing module includes: A multi-channel signal processing unit is used to synchronously process multispectral light intensity signals, perform photoelectric conversion, and output them to the algorithm recognition unit. The algorithm recognition unit is used to identify different spectral feature signals, extract the combustion feature parameters of the flame from ultraviolet radiation spectral feature signals, infrared radiation spectral feature signals, and visible light radiation spectral feature signals, identify the combustion feature parameters of the flame through a pattern recognition algorithm, and match them with a pre-established combustion state model to determine whether the current combustion state of the combustion zone is in a normal or abnormal state. An adaptive analysis unit is used to compare and analyze the combustion state with a pre-established historical database of combustion zones to predict trend changes during the combustion process. The adaptive analysis unit estimates the combustion characteristic parameters of the flame in real time through Kalman filtering, dynamically adjusts the operating parameters of the combustion zone based on the real-time estimates through an adaptive control algorithm, and transmits the analysis results of the operating parameter data to the control module.

6. The apparatus for real-time monitoring of the combustion process according to claim 5, characterized in that, The pattern recognition algorithm is trained using a support vector machine or a neural network to identify the combustion characteristic parameters of the flame.

7. The apparatus for real-time monitoring of the combustion process according to claim 6, characterized in that, The multi-channel signal processing unit synchronously processes multispectral light intensity signals by: eliminating interference signals from non-target bands through optical filters and fusing data from different bands to improve the monitoring accuracy of combustion status.

8. The apparatus for real-time monitoring of the combustion process according to claim 7, characterized in that, The control module includes: The closed-loop control unit is used to dynamically adjust the working parameters of the combustion zone based on the analysis results of the data processing module, thereby achieving closed-loop control. The safety protection unit is used to issue an alarm signal or trigger an emergency shutdown function when the data processing module detects an abnormal combustion result.

9. The apparatus for real-time monitoring of the combustion process according to claim 3, characterized in that, The burner includes: The turbine intake unit is located on the side of the burner and has inclined holes in the same direction as the turbine blades to improve intake efficiency; The cooling unit, located outside the combustion chamber, includes a tightly wound metal tube for introducing coolant or cooling gas to achieve uniform cooling.

10. The apparatus for real-time monitoring of the combustion process according to any one of claims 1-9, characterized in that, It also includes a display and storage module for displaying the combustion characteristic parameters in real time and saving the monitoring data.

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