JP2013072574A - Combustion diagnostic device and method of diagnosing combustion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To not only specify an air ratio with higher accuracy regardless of an input amount of heat but also derive the input amount of heat.SOLUTION: A combustion diagnostic device 100 includes an emission intensity measuring section which measures the intensities of emission to a plurality of predetermined wavelengths featuring flame light generated by combustion, an index deriving section 130 which derives two indexes in response to each of combinations based on a difference or ratio of the emission intensity in each of different two combinations selected from the plurality of wavelengths, and an air ratio deriving section 132 which derives the air ratio with reference to a table or first function predetermined based on the two indexes.

Description

  The present invention relates to a combustion state diagnosis apparatus and a combustion state diagnosis method for diagnosing a combustion state by detecting the state of a flame.

  By detecting the state of the flame (flame state) in the combustion furnace represented by consumer boilers, industrial heating furnaces, etc., and controlling the combustion furnace according to the detection result, the operation state of the combustion furnace is kept normal. be able to. For example, if the flame condition of a pilot burner used for ignition and flame holding of a combustion furnace is detected and it is determined that the original combustion condition is not maintained due to a temporary malfunction or aging deterioration, Execute damage avoidance processing due to.

Thus, for example, techniques for detecting the self-luminous intensity of CH radicals and C ₂ radicals to determine the combustion state of the combustion furnace are disclosed (for example, Non-Patent Document 1, Patent Documents 1 to 3). In particular, Non-Patent Document 1 discloses a technique for obtaining an air ratio based on a function f (I _C2 / I _CH ) having variables of the self-emission intensity I _{CH of the CH} radical and the self-emission intensity I _C2 of the C ₂ radical. Has been.

Further, in addition to the self-emission intensity of CH radicals and C ₂ radicals, a technique for judging a combustion state with reference to a solid radiation spectrum (for example, Patent Document 4), emission intensity of H ₂ O gas (near infrared) A technique for determining a combustion state with reference to light (for example, Patent Document 5) and a technique for determining a combustion state with reference to a power spectrum (for example, Patent Document 6) are also disclosed. As a technique that does not use CH radicals or C ₂ radicals, a technique for obtaining an air ratio using OH emission intensity and fuel flow rate is also disclosed (for example, Patent Document 7).

JP-A-60-169015 Japanese Patent Laid-Open No. 3-207912 JP-A-8-270931 Japanese Patent No. 3035389 Patent No. 3423124 Japanese Patent No. 3852051 JP-A-5-029810

"Fiber-optic air ratio sensor with flame color detection-Performance evaluation by practical use and air ratio control", Takahiro Yamaguchi, Asaharu Yamada, Hironobu Uchiyama, Optics Vol. 24, No. 10 (October 1995), p.638 -p.644

According to the above-mentioned patent documents and non-patent documents, the combustion state of the combustion furnace, particularly the air ratio, can be obtained from the self-emission intensity I _{CH of the CH} radical and the self-emission intensity I _C2 of the C ₂ radical. However, in many practical burners, the air ratio also depends on the input heat amount, and the air ratio cannot be uniquely specified unless the input heat amount is constant. Further, there is a technique for estimating the air ratio alone as the combustion state of the combustion furnace, but there is no technique for comprehensively determining the air ratio and the input heat quantity.

Further, the estimation of the air ratio based on the self-emission intensity I _{CH2 of the CH} radical and the self-emission intensity I _C2 of the C ₂ radical is intended for a flame having a high blue component occupancy (blue flame). The air ratio could not be specified accurately even for a flame including a flame part.

  In view of such a problem, the present invention provides a combustion state diagnostic device and a combustion state diagnostic method capable of specifying the air ratio with higher accuracy regardless of the input heat amount and deriving the input heat amount in parallel. It is intended to provide.

  In order to solve the above problems, the combustion state diagnosis apparatus of the present invention is selected from a plurality of wavelengths, and a light emission intensity measuring unit for measuring light emission intensities with respect to a plurality of predetermined wavelengths that characterize flame light during combustion of the burner An index deriving unit for deriving two indices corresponding to each combination based on the difference or ratio of the emission intensities in two different combinations, and a table or first function determined in advance based on the two indices And an air ratio deriving unit for deriving the air ratio with reference to FIG.

  In order to solve the above-mentioned problem, another combustion state diagnosis apparatus of the present invention is a light emission intensity measuring unit that measures light emission intensity for a plurality of predetermined wavelengths that characterizes flame light during combustion of a burner, and a plurality of wavelengths selected An index deriving unit for deriving two indices corresponding to each combination based on the difference or ratio of the emission intensities in each of the two different combinations, and a table or a predetermined number based on the two indices An input heat quantity deriving unit for deriving the input heat quantity with reference to two functions.

  Flame light is light in which a plurality of light-emitting components having different characteristics are mixed, and the index deriving unit can derive two indices by eliminating the influence of light-emitting components other than the light-emitting components that form the target wavelength. Good.

  The burner may mix the combustion gas and the combustion air immediately before the flame that emits flame light, and burn the mixed premixed gas.

  In order to solve the above-mentioned problem, the combustion state diagnosis method of the present invention measures the emission intensity for a plurality of predetermined wavelengths that characterize the flame light during combustion of the burner, and combines two different combinations selected from the plurality of wavelengths. Two indexes corresponding to each combination are derived based on the difference or ratio of the emission intensity in each, and the air ratio is derived based on the two indexes with reference to a predetermined table or the first function. It is characterized by that.

  In order to solve the above-mentioned problem, another combustion state diagnosis method of the present invention measures the emission intensity for a plurality of predetermined wavelengths that characterize the flame light at the time of combustion of the burner, and selects two different ones selected from the plurality of wavelengths. Based on the difference or ratio of emission intensity in each of the two combinations, two indices corresponding to each combination are derived, and based on the two indices, the input heat quantity is determined with reference to a predetermined table or a second function. It is derived.

  According to the present invention, it is possible to specify the air ratio with higher accuracy regardless of the input heat quantity, and to derive the input heat quantity in parallel.

It is the functional block diagram which showed the schematic structure of the combustion state diagnostic apparatus. It is explanatory drawing for demonstrating five wavelengths measured by the emitted light intensity measurement part. It is explanatory drawing for demonstrating Numerical formula 3 and Numerical formula 4. FIG. It is the flowchart which showed the whole flow of the combustion state diagnostic method. It is explanatory drawing for demonstrating the estimation result of the air ratio by Numerical formula 7. FIG. It is explanatory drawing which showed the derivation | leading-out precision of the air ratio and input calorie | heat amount by a combustion state diagnostic apparatus. It is explanatory drawing for demonstrating a neural network. It is a functional block diagram for demonstrating a modification.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  The combustion state diagnosing device in the present embodiment aims to diagnose the combustion state of the combustion furnace by detecting the state of the flame (flame state), and controls the combustion furnace according to the diagnosed combustion state, and the combustion Keep the furnace operating condition normal. Here, in particular, by detecting the flame condition such as the flame light of the pilot burner and deriving the air ratio and the input heat quantity of the pilot burner, it is possible to maintain the originally required combustion state, or a temporary Comprehensively determine whether there are any problems or deterioration over time.

(Combustion state diagnostic device 100)
FIG. 1 is a functional block diagram showing a schematic configuration of the combustion state diagnostic device 100. The combustion state diagnostic device 100 diagnoses the combustion state of the pilot burner 2 in the combustion furnace 1. The pilot burner 2 is formed including a cylindrical tube 2a extending to the combustion region 3 of the combustion furnace 1, and includes an air introduction hole 2b for introducing air and a gas guide tube 2c for guiding combustion gas to the combustion region 3 side. Prepare. Therefore, since the combustion gas and the combustion air are mixed in the cylindrical tube 2a of the pilot burner 2 (premixing), the flame color of the pilot burner 2 is not only a light emission of a blue flame having a relatively short wavelength, but also a comparison. This includes the emission of luminous flames with long target wavelengths.

  Further, a monitoring window (monitoring hole) 2d is provided at the end (back side) opposite to the ejection direction of the pilot burner 2, so that the flame state of the pilot burner 2 can be monitored from the back side of the flame. The combustion state diagnosis apparatus 100 of the present embodiment detects flame light from the pilot burner 2 from the monitoring window 2d. Therefore, since the blue flame and the bright flame are observed in the extending direction from the monitoring window 2d, the flame lights of both components can be superimposed and extracted at a time.

  The combustion state diagnostic apparatus 100 includes a condenser lens 110, an optical fiber 112, a spectroscope 114, an arithmetic unit 116, and a display unit 118.

  The condensing lens 110 is disposed in the vicinity of the monitoring window 2d on the back side of the pilot burner 2, and condenses the flame light of the pilot burner 2. The optical fiber 112 is disposed at a position facing the flame with the condenser lens 110 interposed therebetween, and transmits the flame light collected by the condenser lens 110 to the spectroscope 114. The spectroscope 114 performs spectrum for each wavelength via the prism 114a and the like, and detects the emission intensity of each wavelength via the light receiving element 114b.

  The arithmetic unit 116 manages and controls the entire combustion state diagnosis apparatus 100 by a semiconductor integrated circuit including a central processing unit (CPU), a ROM storing programs, a RAM as a work area, and the like. The arithmetic unit 116 also functions as an index deriving unit 130, an air ratio deriving unit 132, an input heat amount deriving unit 134, and an abnormality determining unit 136. Such functional units will be described in detail later. The display unit 118 includes a liquid crystal display, an organic EL (Electro Luminescence) display, and the like, and notifies the operator of the combustion state of the combustion furnace 1 and the control amount for the combustion state through an image.

  The condensing lens 110, the optical fiber 112, and the spectroscope 114 function as a light emission intensity measuring unit. The emission intensity measurement unit detects the emission spectrum of the flame light of the pilot burner 2 and measures the emission intensity for a plurality of predetermined wavelengths that characterize the flame light. Here, for example, five wavelengths are given as the plurality of wavelengths.

  FIG. 2 is an explanatory diagram for explaining the five wavelengths measured by the emission intensity measuring unit. 2A shows the flame of the premixed gas targeted by this embodiment, FIG. 2B shows the emission spectrum of a flame in which a bright flame is added to the blue flame, and FIG. Then, the emission spectrum of a flame containing only blue flame is shown. In FIG. 2B and FIG. 2C, spectroscopic analysis is performed in the wavelength range of 350 to 900 nm, emission spectra in the wavelength range are obtained, and emission intensities at five wavelengths are acquired. However, when the wavelength to be measured is determined in advance as in this embodiment, the object can be achieved even if the emission intensity of only that wavelength is acquired. In addition, here, spectroscopic analysis is performed for the wavelength range of 350 to 900 nm for the convenience of the measuring device, but it goes without saying that the target of spectroscopic analysis is not limited to this range.

The target wavelengths are CH radical self-emission intensity I _CH , C ₂ radical self-emission intensity I _C2 , and solid radiation self-emission intensity I _SOOT , CH radical self-emission intensity I _CH , C ₂ radical self-emission intensity I _C2 Are the corrected emission intensities I _a and I _b for deriving a single value of. The CH radical self-emission intensity I _CH is the self-emission intensity characteristic of the blue component of the blue flame, and the C ₂ radical self-emission intensity I _C2 is the self-emission intensity characteristic of the green component of the blue flame. It is. The solid radiation self-emission intensity _ISOOT is an emission intensity of an arbitrary wavelength (here, 635 nm) that characterizes a luminous flame (soot emission) and does not interfere with other chemiluminescence. For the corrected emission intensities I _a and I _b , for example, a wavelength 2.5 nm longer than the CH radical self-emission intensity I _CH and the C ₂ radical self-emission intensity I _C2 is selected. Therefore, when CH radical wavelength I _CH = 431.5 nm and C ₂ radical wavelength I _C2 = 516.5 nm, correction wavelength I _a = 434 nm and correction wavelength I _b = 519 nm. The reason for using the emission intensity of such a correction wavelength will be described below.

In this embodiment, observation is made in the direction of flame extension from the monitoring window 2d in FIG. 1, and as shown in FIG. 2 (b) and FIG. Will be sampled. Therefore, when the luminous flame is included, not only the luminous intensity in the vicinity of the peak of luminous flame emission (in this case, for example, 635 nm) but also the luminous intensity is generated over the blue to green wavelength region. As shown by the curve 150 indicating the wavelength dependence of the light emission intensity, the emission intensity gradually increases from the blue wavelength. This means that the emission intensity of the bright flame affects the emission intensity of the blue flame. In addition to blue flame luminescence (CH radical, C ₂ radical) and luminous flame luminescence (soot blackbody radiation), emission of CO-O bond reaction, etc., which exists gently in the vicinity of 400 to 600 nm, etc. It is also known that the light-emitting components of the superimpose are superimposed.

For example, there is no extreme difference in the emission intensity between the CH radical self-emission intensity I _CH and the C ₂ radical self-emission intensity I _{C2 in} FIG. 2C, but in FIG. Depending on the spectral intensity indicated by the curve 150 rising to the right, the emission intensity of the C ₂ radical self-emission intensity I _C2 is clearly higher than the emission intensity of the CH radical self-emission intensity I _CH. Become. Therefore, here, the spectral intensity due to the luminous flame is excluded, and the independent emission intensity due to the blue flame shown protruding in FIG. 2B is derived.

Specifically, the emission intensity of the luminous flame and other components that are in the vicinity of the CH radical and not affected by the CH radical is detected (here, the emission intensity at the correction wavelength I _a = 434 nm), Subtract from CH radical self-emission intensity I _{CH of} radical = 431.5 nm. In this way, it is possible to eliminate the influence of an unintended light emitting component other than the target blue flame light emission and derive the emission intensity of pure CH radicals. Similarly, a C ₂ radical vicinity, and detects the emission intensity of C ₂ radicals luminous flame or other components unaffected of (in this case, the emission intensity of the compensation wavelength I _{a =} 519 nm), it By subtracting from the C ₂ radical self-emission intensity I _{C2 of} C ₂ radical = 516.5 nm, the emission intensity of the pure C ₂ radical shown protruding in FIG. 2B is derived.

In the present embodiment, the two correction wavelengths use a wavelength obtained by adding 2.5 nm to the CH radical or C ₂ radical. However, the present invention is not limited to this, and if the amount of protrusion of the CH radical or C ₂ radical can be expressed, CH 2 The wavelength to be added to the radical or C ₂ radical can be arbitrarily set, and may be subtracted instead of added.

Further, the wavelength region of the luminous flame emission is also affected by other emission components such as a CO—O bonding reaction. Therefore, the emission intensity at the correction wavelength I _a = 519 nm in the vicinity of the C ₂ radical is expressed by the frequency of solid radiation = Subtract from the solid radiant self-emission intensity _{ISOOT at} 635 nm. In this way, it is possible to derive the emission intensity of pure solid radiation by eliminating the influence of unintended emission components other than the target luminous flame emission.

The index deriving unit 130 derives two indexes corresponding to each combination based on the difference or ratio of the emission intensity in each of the two different combinations selected from the plurality of wavelengths measured by the emission intensity measuring unit. To do. Here, an example is given in which two indices corresponding to two combinations are derived. However, at least two indices are sufficient, and it is also possible to derive many indices by more combinations. Category. Of these two indicators, the first indicator is the ratio between the CH radical self-emission intensity I _CH and the C ₂ radical self-emission intensity I _C2 , but excludes the influence of the luminous flame or other components as described above. Therefore, the ratio is expressed by the following formula 1.
... (Formula 1)
Further, the second index is the emission intensity of solid radiation, but this also excludes the influence of light emission from other components such as CO-O, and its value is expressed by the following mathematical formula 2.
... (Formula 2)

Here, reference is made to the relationship between the first index and the second index, the air ratio λ, and the input heat quantity E, which are preconditions for the processing of the air ratio deriving unit 132 described later. The first index and the second index can be represented by functions using the air ratio λ and the input heat quantity E as variables, as shown in Expression 3 and Expression 4.
... (Formula 3)
... (Formula 4)

  FIG. 3 is an explanatory diagram for explaining the above formulas 3 and 4. FIG. 3A shows the relationship between the air ratio λ and the input heat quantity E and the first index, and FIG. b) shows the relationship between the air ratio λ, the input heat quantity E, and the second index.

Equations 3 and 4 described above are obtained as follows in the preparation stage for carrying out the present embodiment. For example, the air ratio λ to the flame of the pilot burner 2 and the input heat quantity E are objectively obtained by separate means, and five emission intensities (CH radical self-emission intensity I _CH , C ₂ radical self-emission) at that time are obtained. Intensity I _C2 , solid radiation self-emission intensity I _SOOT , corrected emission intensity I _a , I _b ) are measured. Then, when the first index is plotted against the air ratio λ and the input heat quantity E and the approximate curved surface is generated, the relationship between the air ratio λ and the input heat quantity E versus the first index can be derived as shown in FIG. . Similarly, when the second index is plotted against the air ratio λ and the input heat amount E and the approximate curved surface is generated, the relationship between the air ratio λ and the input heat amount E versus the second index is derived as shown in FIG. it can.

  As can be understood with reference to FIG. 3, when the air ratio λ and the input heat quantity E are determined, the first index and the second index each have a value of 1. Below, using such a relationship, conversely, the air ratio λ and the input heat quantity E are derived from the first index and the second index.

The air ratio deriving unit 132 derives the air ratio based on two indices (first index and second index). The air ratio λ can be derived from Equation 5 as the first function, which is the solution of the simultaneous equations of Equation 3 and Equation 4.
... (Formula 5)

Therefore, if the relationship between Equation 3 and Equation 4 is obtained in advance by experiments or the like, Equation 5 can be derived therefrom. Thus, the first index is determined by the emission intensity of five wavelengths in flame light (CH radical self-emission intensity I _CH , C ₂ radical self-emission intensity I _C2 , solid radiation self-emission intensity I _SOOT , corrected emission intensity I _a , I _b ). As long as the second index is specified, the air ratio λ can be easily derived.

The input heat quantity deriving unit 134 derives the input heat quantity based on two indices (first index and second index). The input heat quantity E can be derived by Expression 6 as a second function, which is a solution of the simultaneous equations of Expression 3 and Expression 4.
... (Formula 6)

  Therefore, as in Equation 5, if the relationship between Equation 3 and Equation 4 is obtained in advance by experiments or the like, Equation 6 can be derived therefrom. In this way, the input heat quantity E can be easily derived as long as the first index and the second index are specified by the five emission intensities in the flame light.

  However, since Equation 5 and Equation 6 correspond to the solutions of the simultaneous equations of Equation 3 and Equation 4, the order often extends to a higher order, and when the processing capability of the arithmetic unit 116 is low, the air ratio deriving unit 132 or There is a possibility that the processing load in the input heat quantity deriving unit 134 may increase. Therefore, here, the mathematical formula 5 and the mathematical formula 6 are a table that uniquely derives the air ratio λ and the input heat quantity E from the plurality of equally divided first indexes and the plurality of equally divided second indexes. Let's represent. By using such a table, the air ratio λ and the input heat quantity E can be accurately and quickly derived without performing calculation with a high processing load. At this time, for a portion that is not a representative value of the first index or the second index, that is, for a portion for which no specific numerical value is set in the table, a value in the vicinity of the air ratio λ or the input heat amount E is used. Interpolation (for example, linear interpolation) may be performed. However, it goes without saying that Formula 5 and Formula 6 may be directly derived.

  The abnormality determining unit 136 determines whether or not the air ratio λ derived by the air ratio deriving unit 132 and the input heat amount E derived by the input heat amount deriving unit 134 are included in a predetermined allowable range. In this case, for example, the operator is notified through the display unit 118. Below, the flow of the whole operation | movement of the combustion state diagnostic apparatus 100 is demonstrated.

(Combustion state diagnosis method)
FIG. 4 is a flowchart showing the overall flow of the combustion state diagnosis method. The combustion state diagnosing method is started by a periodic timer interruption at a predetermined time interval.

When the timer interruption occurs, first, the emission intensity measurement unit of the combustion state diagnostic device 100 emits the emission intensities (CH radical self-emission intensity I _CH , C ₂ radical) for the five wavelengths that characterize the flame light during combustion of the pilot burner 2. Self-luminous intensity I _C2 , solid-radiation self-luminous intensity I _SOOT , corrected luminous intensity I _a , I _b ) are measured (S200), and the index deriving unit 130 in each of two different combinations selected from a plurality of wavelengths , The difference or ratio of emission intensity (the ratio of the values obtained by subtracting the corrected emission intensity I _a and I _b from the CH radical spontaneous emission intensity I _CH and the C ₂ radical spontaneous emission intensity I _C2 shown in Equation 1, respectively, and shown in equation 2, it derives the two indices based on the solid radiation self-emission intensity _{I SOOT} difference correction luminous intensity _{I b)} (S202).

  Subsequently, the air ratio deriving unit 132 derives the air ratio λ by referring to a predetermined table based on the two indexes (S204), and the input heat quantity deriving unit 134 based on the two indexes. The input heat quantity E is derived with reference to a predetermined table (S206). Then, the abnormality determination unit 136 determines whether the air ratio λ derived by the air ratio deriving unit 132 and the input heat amount E derived by the input heat amount deriving unit 134 are included in a predetermined allowable range (S208). If not included (NO in S208), the fact is notified to the outside (S210). If it is included in the allowable range (YES in S208), the process ends and returns to the interrupt standby state.

  With such a combustion state diagnostic device 100 and a combustion state diagnostic method, it is possible to specify the air ratio with higher accuracy regardless of the input heat amount and to derive the input heat amount in parallel.

(Verification of effect)
Hereinafter, the effect of the combustion state diagnosis apparatus 100 according to the present embodiment will be verified. The air ratio λ depends on the CH radical self-emission intensity I _CH and the C ₂ radical self-emission intensity I _C2 . Conventionally, the air ratio λ has been obtained based on Equation 7, which is a function having the CH radical self-emission intensity I _CH and the C ₂ radical self-emission intensity I _C2 as variables.
... (Formula 7)
However, although Equation 7 is satisfied under a condition where the input heat quantity is constant, the air ratio cannot be uniquely specified when the input heat quantity is unknown.

FIG. 5 is an explanatory diagram for explaining the estimation result of the air ratio according to Equation 7. For example, in the pilot burner 2 that is the subject of the present embodiment, as shown in FIG. 5A, five air ratios (0.30, 0.40, 0.50, 0.60, 0.70) 5 radicals multiplied by 5 input calories (3.07 kW, 3.45 kW, 3.84 kW, 4.22 kW, 4.61 kW) are used to generate a flame, and CH radical spontaneous emission intensity The I _CH and C ₂ radical spontaneous emission intensity I _C2 was detected, and the peak ratio of the index I _C2 / I _CH was derived as shown in FIG.

According to Equation 7, the air ratio λ is uniquely determined by the index I _C2 / I _CH . Therefore, if the index I _C2 / I _CH indicates a fixed value, the air ratio λ should also be a fixed value. However, in FIG. 5B, for example, at the position of the index I _C2 / I _CH = 1.4, the air ratio has three values of 0.5, 0.6, and 0.7 according to the input heat quantity. Can take. That is, it can be understood that the air ratio λ cannot be specified from the index I _C2 / I _CH even if the index I _C2 / I _CH is a fixed value.

On the other hand, in the combustion state diagnosis apparatus 100 in the present embodiment, the following effects can be obtained. Here, the air ratio λ to the flame of the pilot burner 2 and the input heat quantity E are objectively obtained by separate means, and the five emission intensities of the flame light at that time are measured. Equation 9 corresponding to Equation 4 is derived in advance.
... (Formula 8)
... (Formula 9)
Then, based on Equation 8 and Equation 9, the values of the first index and the second index when the air ratio λ and the input heat amount E are changed in various combinations are taken, and the table regarding the air ratio λ and the input heat amount E is obtained. Turn into.

After preparation for measurement, a flame is generated by the 25 combinations shown in FIG. 5A as before, and emission intensities for five wavelengths (CH radical self-emission intensity I _CH , C ₂ radical self-emission intensity I _C2 , solid radiation self-emission intensity _ISOOT , corrected emission intensity _Ia , _Ib ), the first index and the second index are obtained, and the air that satisfies Formula 8 and Formula 9 consistently with reference to the above table The ratio λ and the input heat quantity E are obtained.

  FIG. 6 is an explanatory diagram showing the accuracy of deriving the air ratio λ and the input heat quantity E by the combustion state diagnostic device 100 in the present embodiment. 6A shows the accuracy of the air ratio λ, and FIG. 6B shows the accuracy of the input heat quantity E. 6A and 6B, it is possible to grasp an error between the actually set true values of the air ratio λ and the input heat quantity E and the estimated values obtained by the combustion state diagnostic device 100 of the present embodiment. According to FIGS. 6A and 6B, it can be understood that the error of the air ratio λ is included in a range of approximately ± 0.1, and the error of the input heat quantity E is included in a range of approximately ± 1 kW. Therefore, conventionally, the value may be different from the true value by 0.2 or more depending on the amount of input heat. However, in the combustion state diagnosis apparatus 100 of the present embodiment, it is possible to estimate with high accuracy such as 0.1 or less. .

  With the combustion state diagnostic device 100 and the combustion state diagnostic method described above, it is possible to specify the air ratio λ with higher accuracy and derive the input heat amount E regardless of the input heat amount E. Since the air ratio λ and the input heat quantity E can be obtained from the same two indexes (first index and second index), the air ratio can be easily obtained by deriving the first index and the second index. It is possible to derive λ and the input heat quantity E at the same time.

  In addition, since the flame state of the pilot burner 2 installed in the combustion furnace 1 can be easily diagnosed by the external combustion state diagnostic apparatus 100, the air ratio λ and the input heat quantity E can be estimated with high accuracy regardless of whether the flame burner is newly installed or existing. In addition, since the constituent elements are small and light, they are excellent in portability, and can be applied to either permanent installation or mobile use.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

For example, in the above-described embodiment, Equation 5 is obtained from five emission intensities (CH radical self-emission intensity I _CH , C ₂ radical self-emission intensity I _C2 , solid radiation self-emission intensity I _SOOT , corrected emission intensity I _a , I _b ). In addition, the example in which the air ratio λ and the input heat quantity E are uniquely obtained has been described using Equation 6 or a table. And the input heat quantity E may be derived. Here, the following formulas 10 and 11 are used.
... (Formula 10)
... (Formula 11)
First, a network is constructed using the input signal P and the teacher signal T. That is, the weights V and W and the biases B and C are obtained. And the output layer R is calculated | required only by the input of the input signal P using the constructed | assembled network. The output layer R is an estimated value and should be close to the teacher signal T. Here, the input signal P corresponds to the indexes 1 and 2 of the present embodiment, and the output layer R corresponds to the air ratio λ and the input heat amount E.

  In the above-described embodiment, the emission intensity measurement unit is configured by a combination of the condenser lens 110, the optical fiber 112, and the spectroscope 114. However, the present invention is not limited to this, and an optical fiber as illustrated in FIG. A configuration in which a spectroscopic element 160 such as a diffraction grating is disposed instead of 112 and the dispersed light is received by each of the plurality of light receiving elements 162, or in place of the spectroscopic element 160 such as a diffraction grating as shown in FIG. In addition, various configurations such as a configuration in which a plurality of wavelength filters 164 that reflect only a specific wavelength are arranged and light is received by the light receiving element 162 can be applied. In addition to the spectroscopic measurement method described above, an image measurement method using a color imaging device or the like can be used.

  Also provided are a program that causes the computer to function as the combustion state diagnostic apparatus 100 and a storage medium such as a computer-readable flexible disk, magneto-optical disk, ROM, EPROM, EEPROM, CD, DVD, or BD on which the program is recorded. Is done. Here, the program refers to data processing means described in an arbitrary language or description method.

  Note that each step in the combustion state diagnosis method of the present specification does not necessarily have to be processed in time series in the order described in the flowchart, and may include processing in parallel or by a subroutine.

  INDUSTRIAL APPLICABILITY The present invention can be used for a combustion state diagnosis apparatus and a combustion state diagnosis method that diagnose a combustion state by detecting a flame state.

DESCRIPTION OF SYMBOLS 1 ... Combustion furnace 2 ... Pilot burner 100 ... Combustion state diagnostic apparatus 110 ... Condensing lens 112 ... Optical fiber 114 ... Spectroscope 116 ... Calculation unit 118 ... Display part 130 ... Indicator | lead-out part 132 ... Air ratio derivation part 134 ... Input heat amount Derived part

Claims (6)

A light emission intensity measuring unit that measures light emission intensity for a plurality of predetermined wavelengths that characterize flame light during burner combustion;
An index deriving unit for deriving two indices corresponding to each combination based on a difference or ratio of emission intensity in each of two different combinations selected from the plurality of wavelengths;
An air ratio deriving unit for deriving an air ratio with reference to a predetermined table or a first function based on the two indexes;
A combustion state diagnosis apparatus comprising: A light emission intensity measuring unit that measures light emission intensity for a plurality of predetermined wavelengths that characterize flame light during burner combustion;
An index deriving unit for deriving two indices corresponding to each combination based on a difference or ratio of emission intensity in each of two different combinations selected from the plurality of wavelengths;
An input heat quantity deriving unit that derives an input heat quantity with reference to a predetermined table or a second function based on the two indexes;
A combustion state diagnosis apparatus comprising: The flame light is light in which a plurality of light emitting components having different characteristics are mixed,
3. The combustion state diagnosis apparatus according to claim 1, wherein the index deriving unit derives the two indices by excluding the influence of a light emitting component other than a light emitting component that forms a target wavelength. 4.   4. The burner according to claim 1, wherein the burner mixes combustion gas and combustion air immediately before the flame that emits the flame light, and burns the mixed pre-mixed gas. 5. Combustion state diagnostic device. Measure the emission intensity for a given number of wavelengths that characterize the flame light when burning the burner,
Deriving two indices corresponding to each combination based on a difference or ratio of emission intensity in each of two different combinations selected from the plurality of wavelengths,
A combustion state diagnosing method, wherein an air ratio is derived based on the two indexes with reference to a predetermined table or a first function. Measure the emission intensity for a given number of wavelengths that characterize the flame light when burning the burner,
Deriving two indices corresponding to each combination based on a difference or ratio of emission intensity in each of two different combinations selected from the plurality of wavelengths,
A combustion state diagnosing method, wherein the input heat quantity is derived by referring to a predetermined table or a second function based on the two indexes.