Heat flux acquisition device, heat flux acquisition system, and heat flux acquisition method for heating furnace

Abstract

[Problem] To easily obtain the local heat flux of an object in a heating furnace. [Solution] A heat flux acquisition device 4 comprises a processor that executes a process for acquiring the heat flux of an object 12 in a heating furnace 2. The processor acquires an object point temperature measured by a temperature sensor 23 for the object point on the outer surface of the object 12, acquires the environmental temperature corresponding to the object point, and calculates the local heat flux for the object point on the basis of the object point temperature and the corresponding environmental temperature.

Description

Heat flux acquisition device, heat flux acquisition system, and heat flux acquisition method for heating furnace

[0001] The present invention relates to a heat flux acquisition device, a heat flux acquisition system, and a heat flux acquisition method for acquiring the heat flux of an object in a heating furnace.

[0002] A conventional method for estimating the outer surface temperature of a coil in an ethylene cracking furnace is known, which estimates the outer surface temperature of the coil by reflecting the temperature of a relatively high-temperature portion in the imaged region, even if that portion has a relatively high temperature (see Patent Document 1). In this conventional method, an imaging camera for imaging the imaged region of the coil is used, which may be a color video camera that outputs the luminance at each light-receiving pixel for each RGB wavelength, a monochrome video camera that measures the luminance at a single wavelength of 1 μm or more and less than 3 μm, or a dual-sensor camera that measures the ratio of the luminance at a first wavelength and a second wavelength of 1 μm or more and less than 3 μm.

[0003] Furthermore, a method for measuring the radiant heat flux on the exterior surface of a building is known, which aims to quantitatively measure the radiant heat flux on the exterior surface of a building based on infrared imaging technology (see Patent Document 2). In this conventional method, to determine the net radiant heat flow on the exterior surface of a building, infrared thermography images are taken and the obtained images are analyzed.

[0004] Patent No. 7111583 Chinese Patent Application Publication No. 113970388

[0005] In a heating furnace used as a plant facility, the heat flux on the heating pipes and the like is an important index relating to various phenomena in the heating furnace (for example, the occurrence of coking and film boiling).

[0006] On the other hand, while methods for estimating or measuring the temperature or heat flux of an object using a camera or thermography are known, such as the conventional techniques described in Patent Documents 1 and 2 above, methods for easily obtaining the heat flux (i.e., local heat flux) at a desired location of an object inside a heating furnace are not widely used.

[0007] In view of the above background, an object of the present invention is to provide a heat flux acquisition device, a heat flux acquisition system, and a heat flux acquisition method that can easily acquire the local heat flux of an object in a heating furnace.

[0008] In order to solve the above problem, one aspect of the present invention is a heat flux acquisition device (4) that acquires the heat flux of an object (12) in a heating furnace (2), and includes a processor that executes processing to acquire the heat flux of the object, wherein the processor acquires an object point temperature measured by a temperature sensor (23) for an object point on the outer surface of the object, acquires an environmental temperature corresponding to the object point, and calculates a local heat flux for the object point based on the object point temperature and the corresponding environmental temperature.

[0009] According to this aspect, the local heat flux of the object in the heating furnace can be easily obtained.

[0010] In the above aspect, the local heat flux may be calculated based on the energy radiated toward the object, which is calculated based on the ambient temperature, and the energy radiated from the object, which is calculated from the object point temperature.

[0011] According to this aspect, the local heat flux of the object in the heating furnace can be easily calculated based on the environmental temperature and the temperature at the object point.

[0012] In the above aspect, the heating furnace may be a tubular heating furnace (2), and the object may include a heating tube (12) of the tubular heating furnace.

[0013] According to this aspect, the local heat flux of the heating tube in the heating furnace can be easily obtained.

[0014] In the above aspect, the environmental temperature may be an estimated environmental temperature estimated based on the temperature of the corresponding target point when the target point is measured by a thermograph (22).

[0015] According to this aspect, the accuracy of the environmental temperature can be improved by obtaining an environmental temperature estimated based on measurements of the target point using thermography (i.e., estimated environmental temperature).

[0016] In the above aspect, the environmental temperature is a corrected environmental temperature obtained by calculation, and the heating pipe has one or more segments (G １ -G ９ ) and a plurality of target points (P １－１ -P １－８ ), and the corrected ambient temperature may be calculated based on at least the target point temperatures measured by the temperature sensors for each of the target points, the heat quantity of the heated fluid flowing into the heating pipe, and the heat quantity of the heated fluid flowing out of the heating pipe.

[0017] According to this aspect, the accuracy of the environmental temperature can be improved by acquiring the environmental temperature corrected based on the heat quantity of the fluid to be heated (i.e., corrected environmental temperature).

[0018] In the above aspect, the processor may acquire each of the target point temperatures, acquire an estimated environmental temperature inside the furnace corresponding to each of the segments, which is estimated based on the corresponding target point temperatures, calculate an estimated local heat flux for each of the target points based on each of the target point temperatures and the estimated environmental temperature corresponding thereto, calculate an estimated segment average heat flux or estimated segment heat input for each of the segments based on the estimated local heat flux, acquire an estimated average heat flux or estimated heat input for the heating pipe based on the estimated segment average heat flux or estimated segment heat input, calculate an actual average heat flux or actual heat input for the heating pipe based on the heat quantity of the heated fluid flowing into the heating pipe and the heat quantity of the heated fluid flowing out of the heating pipe, and calculate the corrected environmental temperature by correcting the estimated average heat flux to match the actual average heat flux or the estimated heat input to match the actual heat input.

[0019] According to this aspect, the accuracy of the environmental temperature can be improved by calculating a corrected environmental temperature (i.e., corrected environmental temperature) using the heat flux or heat input of each segment based on each target point temperature and the corresponding estimated environmental temperature (i.e., estimated segment heat flux or estimated segment heat input) and the heat flux or heat input based on the heat quantity of the heated fluid (i.e., actual average heat flux or actual heat input).

[0020] In the above aspect, each of the segments includes a sub-segment (G １－１ -G １－８ ), and the processor calculates the surface area (s １－１ -s １－８ ) as weights of the local heat fluxes for the corresponding points of interest, and the estimated segment average heat flux for each of the segments is calculated based on a weighted average.

[0021] According to this aspect, by taking into consideration the surface area of ​​each sub-segment set corresponding to each target point, the heat flux for each segment can be obtained with high accuracy.

[0022] In the above aspect, the heating pipe has a plurality of segments including one representative segment and subordinate segments other than the representative segment, the estimated ambient temperature of the subordinate segment is expressed using a temperature ratio to the estimated ambient temperature of the representative segment, and the processor calculates the corrected ambient temperature of the representative segment and calculates the corrected ambient temperature of the subordinate segment based on the corrected ambient temperature of the representative segment and the temperature ratio.

[0023] According to this aspect, the corrected environmental temperature of the subordinate segment is calculated based on the corrected environmental temperature of the representative segment, so that the corrected environmental temperature of each segment can be easily obtained.

[0024] In the above aspect, it is preferable to further include a storage device (32) that stores the temperature ratio between the estimated environmental temperature of the subordinate segment and the estimated environmental temperature of the representative segment.

[0025] According to this aspect, it becomes easy to use the temperature ratio between the estimated environmental temperature of the subordinate segment and the estimated environmental temperature of the representative segment.

[0026] In the above aspect, the processor may acquire the temperature of each target point, acquire the corrected ambient temperature of the representative segment and the corrected ambient temperature of the subordinate segment, and calculate the local heat flux for the target point based on the target point temperature and the corresponding corrected ambient temperature of the representative segment and the corrected ambient temperature of the subordinate segment.

[0027] According to this aspect, by utilizing the temperature ratios obtained in the past, even if the operating conditions of the heating furnace 2 are changed, the corrected ambient temperature of each subordinate segment can be easily calculated from the corrected ambient temperature of the representative segment, thereby reducing the load of the calculation process of the local heat flux for each target point.

[0028] In the above aspect, the processor may further calculate a target point temperature for the target point based on the corrected environmental temperature of the representative segment and the corrected environmental temperature of the subordinate segment.

[0029] According to this aspect, the target point temperature can be obtained without the need for measurement.

[0030] In the above aspect, the system may further include a storage device (32), and the processor may further calculate an actual average heat flux related to the heating pipe based on the heat quantity of the heated fluid flowing into the heating pipe and the heat quantity of the heated fluid flowing out of the heating pipe, calculate a heat flux ratio between the actual average heat flux and the local heat flux, and store the heat flux ratio in the storage device.

[0031] According to this aspect, it becomes easy to utilize the heat flux ratio between the actual average heat flux and the local heat flux.

[0032] In the above aspect, the processor may acquire the heat flux ratio stored in the storage device, calculate an actual average heat flux for the heating pipe based on the heat quantity of the heated fluid flowing into the heating pipe and the heat quantity of the heated fluid flowing out of the heating pipe, and acquire the local heat flux based on the heat flux ratio and the actual average heat flux.

[0033] According to this aspect, by using the heat flux ratio obtained in the past, the load of the calculation process of the local heat flux is reduced. In particular, there is an advantage that it is not necessary to measure the target point temperature of the heating pipe, and it is not necessary to obtain the environmental temperature or to correct it.

[0034] In the above aspect, the present invention may further include a storage device, and the processor may store the operating conditions of the heating furnace and the environmental temperature under those operating conditions in the storage device, and construct a machine learning model that uses the operating conditions stored in the storage device as input and outputs the environmental temperature.

[0035] According to this aspect, it is possible to accurately obtain the corresponding environmental temperature from the current operating conditions (or planned operating conditions) using a machine learning model constructed based on the past operating conditions of the heating furnace and the environmental temperature under those operating conditions.

[0036] In the above aspect, the processor may acquire the ambient temperature by inputting new operating conditions of the heating furnace into the machine learning model, and calculate the local heat flux based on the acquired ambient temperature and the target point temperature on the outer surface of the object.

[0037] According to this aspect, the local heat flux can be calculated with high accuracy based on the environmental temperature acquired by the machine learning model.

[0038] In the above aspect, the operating conditions may include combustion conditions of the heating furnace and operating conditions of a burner in the heating furnace.

[0039] According to this aspect, the environmental temperature (and therefore the local heat flux) can be obtained with high accuracy using appropriate operating conditions.

[0040] In the above aspect, the temperature sensor may include a wavelength distribution type radiation thermometer.

[0041] According to this aspect, even if the measurement is performed without contact with the measurement target, the temperature at the target point can be obtained with high accuracy.

[0042] In the above aspect, the processor may generate an image that visualizes the distribution of the local heat flux.

[0043] According to this aspect, the user can easily check various phenomena occurring inside the heating furnace (for example, the occurrence of coking or film boiling) based on the image that visualizes the distribution of local heat flux.

[0044] In the above aspect, the heating tube has one or more segments (G １ -G ９ ) and a plurality of target points set for each of the segments, and the processor may use the estimated environmental temperature to obtain a temperature distribution of the object measured by a thermograph (32).

[0045] According to this aspect, it is possible to obtain the temperature of an object in a heating furnace over a wide range using thermography.

[0046] In the above aspect, the processor may acquire the temperature in the temperature distribution of the object as the object point temperature.

[0047] This embodiment provides a greater degree of freedom in setting the target point on the object, and also has the advantage of making it possible to easily obtain the temperature of the target point over a wide range of the object.

[0048] In order to solve the above problem, one aspect of the present invention is a heat flux acquisition system including the above heat flux acquisition device, which is configured to include a wavelength distribution type radiation thermometer (23) included in the temperature sensor and a thermograph (22) for acquiring the environmental temperature.

[0049] According to this aspect, the local heat flux of the object in the heating furnace can be easily obtained.

[0050] In order to solve the above problem, one aspect of the present invention is a heat flux acquisition method for acquiring the heat flux of an object (12) in a heating furnace (2), in which a computer (4) acquires an object point temperature measured by a temperature sensor (12) for an object point on the outer surface of the object, acquires an environmental temperature corresponding to the object point, and calculates a local heat flux for the object point based on the object point temperature and the corresponding environmental temperature.

[0051] According to this aspect, the local heat flux of the object in the heating furnace can be easily obtained.

[0052] According to the above aspect, the local heat flux of the object in the heating furnace can be easily obtained.

[0053] 1. Overall configuration diagram of a heat flux acquisition system 1 according to an embodiment. 2. Block diagram of a heat flux acquisition device 4. 3. Schematic diagram showing an example of the configuration inside a heating furnace 2. 4. Flow diagram showing the flow of heat flux acquisition processing by the heat flux acquisition device 4. 5. Flow diagram showing a first modified example of the heat flux acquisition processing shown in FIG. 4. 6. Flow diagram showing a second modified example of the heat flux acquisition processing shown in FIG. 4.

[0054] Hereinafter, a heat flux acquisition device, a heat flux acquisition system, and a heat flux acquisition method for a heating furnace according to an embodiment of the present invention will be described with reference to the drawings.

[0055] 1 , the heat flux acquisition system 1 includes an on-site facility 3 for acquiring various information and measurement data related to the heating furnace 2. The heat flux acquisition system 1 also includes a heat flux acquisition device 4 for acquiring the heat flux of an object in the heating furnace 2. The on-site facility 3 and the heat flux acquisition device 4 can communicate with each other via a communication network 5 such as a local area network (LAN) or the Internet. However, the on-site facility 3 and the heat flux acquisition device 4 may also be directly connected by a communication cable.

[0056] The heating furnace 2 has a known configuration used as plant equipment. Here, the heating furnace 2 is a tubular heating furnace, but it may have other configurations. A heating pipe 12 through which the fluid to be heated flows and a combustion device 13 including a burner are provided inside the casing 11 (i.e., inside the heating furnace 2). The heating pipe 12 is formed of a circular pipe, but it may have other configurations. The heating pipe 12 is heated by the heat of the flame or combustion gas of the combustion device 13. The heating furnace 2 is provided with an upper area 14 that heats (or preheats) the fluid to be heated, and a lower area 15 that heats the fluid to be heated that has been heated in the upper area 14. Although not shown, a plurality of observation windows are provided in appropriate positions (e.g., on the side wall) of the casing 11 to allow observation inside the heating furnace 2.

[0057] In this embodiment, the heating tube 12, which is heated mainly by radiative heat transfer (i.e., radiation heat transfer), will be described as an example of the target (i.e., object) from which heat flux is acquired in the heating furnace 2. However, the target from which such heat flux is acquired is not limited to the heating tube 12, and may be another component (e.g., the inner wall of the casing 11) in the heating furnace 2. Furthermore, for example, a slab in a heating furnace for slab heating may be the target from which heat flux is acquired.

[0058] The field equipment 3 includes a measuring device 21 for the heated fluid, a thermograph 22, a two-color thermometer 23 (an example of a temperature sensor), and a terminal device 24.

[0059] The measuring instruments 21 for the heated fluid are attached to appropriate positions of the heating pipe 12 (for example, the inlet, outlet, and intermediate portion of the heated fluid in the heating pipe 12). The measuring instruments 21 may include a thermometer, a flow meter, a pressure gauge, etc. for measuring the temperature, flow rate, and pressure of the heated fluid, respectively.

[0060] The thermograph 22 has a known configuration and measures the outer surface temperature of the heating tube 12 in a predetermined measurement area in a non-contact manner based on infrared rays radiated from the heating tube 12 in the heating furnace 2. Measurement by the thermograph 22 is performed through a viewing window in the heating furnace 2. A plurality of thermographs 22 may be provided to simultaneously measure a plurality of measurement areas on the heating tube 12.

[0061] The two-color thermometer 23 has a known configuration and measures the temperature (hereinafter referred to as the target point temperature) of a predetermined portion on the outer surface of the heating tube 12 (hereinafter referred to as the target point) in a non-contact manner based on two different measurement wavelengths. Measurement by the two-color thermometer 23 is performed through a sight glass, similar to the thermography 22. Multiple two-color thermometers 23 may be provided to simultaneously measure multiple target points on the heating tube 12. Note that measurement of the target point temperature of the heating furnace 2 is not limited to the two-color thermometer 23, and may also be performed by other wavelength distribution type radiation thermometers. In some cases, measurement of the target point temperature of the heating furnace 2 may be performed by a known thermometer (e.g., a thermocouple) installed in advance in the heating furnace 2.

[0062] The terminal device 24 collects various measurement data measured regarding the heating furnace 2. Such measurement data includes data measured by the heated fluid measuring device 21, the thermograph 22, and the two-color thermometer 23. Furthermore, the measurement data may include data obtained by performing predetermined arithmetic processing using the measured data (i.e., indirectly measured data). The terminal device 24 is communicatively connected to the heat flux acquisition device 4 via the communication network 5 and transmits the collected measurement data to the heat flux acquisition device 4 as appropriate. The terminal device 24 also stores specification data of the heating furnace 2 and can transmit the data to the heat flux acquisition device 4. The specification data of the heating furnace 2 includes data required for arithmetic processing to acquire the heat flux by the heat flux acquisition device 4 (e.g., data related to the physical properties, size, position, etc. of the heating pipe 12). The terminal device 24 may be used as a control device for controlling the operation of the heating furnace 2.

[0063] The terminal device 24 is configured by a computer equipped with known hardware. The terminal device 24 appropriately includes known hardware such as one or more processors, memory, display, input device, network interface, and storage. At least some of the functions of the terminal device 24 can be realized by the processor executing a predetermined control program. Note that in the heat flux acquisition system 1, at least some of the functions of the terminal device 24 described above may be realized by multiple computers working together.

[0064] The terminal device 24 may be a mobile device such as a tablet PC or smartphone with a communication function carried by a user of the heat flux acquisition system 1 (e.g., an operator or manager of the heating furnace 2). Furthermore, at least some of the functions of the terminal device 24 (e.g., a function to transmit measurement data to the heat flux acquisition device 4) may be included in the measuring instrument 21, the thermograph 22, and the two-color thermometer 23.

[0065] Next, the heat flux acquisition device 4 will be described in detail.

[0066] As shown in FIG. 2 , the heat flux acquisition device 4 includes a control unit 31 , a storage unit 32 , and a communication unit 33 .

[0067] In the control unit 31, the data acquisition unit 41 acquires measurement data and specification data related to the heating furnace 2 received from the terminal device 24 via the communication unit 33. The measurement data obtained by the measuring instrument 21 and the specification data of the heating furnace 2 are stored in the memory unit 32 as heating furnace data 51. Measurement data related to the temperature of the heating tube 12 obtained by the thermograph 22 and the two-color thermometer 23 is stored in the memory unit 32 as heating tube temperature data 52. Measurement data related to the environmental temperature (i.e., the temperature around the heating tube 12 in the heating furnace 2) obtained by the thermograph 22 is stored in the memory unit 32 as environmental temperature data 53. Within the heating furnace 2, the corresponding environmental temperature varies depending on the position of the heating tube 12 (e.g., its position relative to the flame of the combustion device 13). As described below, the environmental temperature is indirectly measured by the thermograph 22 (i.e., calculated or estimated based on other measured data).

[0068] The heating furnace data 51 includes position data within the heating furnace 2. Such position data may include, for example, global coordinate data corresponding to the position of each target point on the heating pipe 12. The positions of the measurement points measured by the thermograph 22 or two-color thermometer 23 can also be determined using global coordinates (i.e., the measured temperature, etc. can be associated with the global coordinates). However, coordinate data uniquely set for the heating furnace 2 may also be used as the position data within the heating furnace 2.

[0069] The heat flux calculation unit 42 calculates a local heat flux (an example of an estimated local heat flux) at a target point on the heated pipe 12 based on the heated pipe temperature data 52 (here, the target point temperature of each target point) and the environmental temperature data 53 (here, the environmental temperature corresponding to each target point). As will be described later, the heat flux calculation unit 42 may calculate the local heat flux based on a corrected environmental temperature. Furthermore, the heat flux calculation unit 42 can calculate an average heat flux for the entire heated pipe 12 (hereinafter referred to as an estimated average heat flux) based on the local heat fluxes at a plurality of target points. However, the estimated average heat flux does not necessarily have to be a heat flux for the entire heated pipe 12, but may be a heat flux for a predetermined section of the heated pipe 12 (for example, a segment G described later). １ -G ９ ) may be the heat flux with respect to

[0070] Note that the heat flux calculation unit 42 may calculate the amount of heat input to the entire heating pipe 12 (hereinafter referred to as the estimated average heat input amount) based on the heat input amounts at a plurality of target points, instead of or together with the estimated average heat flux.

[0071] Furthermore, the heat flux calculation unit 42 can calculate an average heat flux for the entire heating pipe 12 (hereinafter referred to as actual average heat flux) based on the heat quantity of the heated fluid flowing into the heating pipe 12 and the heat quantity of the heated fluid flowing out of the heating pipe 12 (i.e., the heat input quantity to the heated fluid that has flowed through the heating pipe 12). The actual average heat flux does not necessarily have to be the heat flux for the entire heating pipe 12, but can be calculated for a predetermined section of the heating pipe 12 (for example, a segment G described later). １ -G ９) may be the heat flux with respect to

[0072] The heat flux calculation unit 42 may calculate or estimate the amount of heat input to the entire heating pipe 12 (hereinafter referred to as the actual average heat input amount) from the amount of heat input to the heated fluid that has flowed through the entire heating pipe 12, instead of or together with the actual average heat flux. １ -G ９ The actual average heat input may be calculated or estimated from the sum of the heat inputs to the heated fluid flowing through the

[0073] Data regarding the local heat flux, estimated average heat flux, estimated average heat input, actual average heat flux, actual average heat input, etc. calculated by the heat flux calculation unit 42 are stored in the memory unit 32 as heat flux data 54.

[0074] As will be described in detail later, the heat flux calculation unit 42 can calculate the heat flux ratio between the actual average heat flux and the local heat flux at each target point and store the calculated heat flux data 54 in the storage unit 32. This allows the heat flux calculation unit 42 to calculate the local heat flux based on the previously calculated heat flux ratio data and the actual average heat flux, even if the operating conditions are changed. The heat flux ratio data is stored in the storage unit 32 as part of the heat flux data 54.

[0075] The environmental temperature correction unit 43 obtains a corrected environmental temperature by correcting the environmental temperature received from the terminal device 24 based on the estimated average heat flux and the actual average heat flux. The corrected environmental temperature data calculated by the environmental temperature correction unit 43 is stored in the storage unit 32 as environmental temperature data 53. More specifically, when the corrected environmental temperature is calculated by the environmental temperature correction unit 43, the environmental temperature already stored in the storage unit 32 is updated with the corrected environmental temperature. Note that the environmental temperature correction unit 43 may obtain the corrected environmental temperature by correcting an initial value of the environmental temperature previously stored in the storage unit 32, instead of the environmental temperature received from the terminal device 24.

[0076] The heat flux distribution generating unit 44 generates an image (hereinafter referred to as a heat flux visualization image) that visualizes the distribution of local heat fluxes at multiple target points on the heating pipe 12 using a color scheme (i.e., color changes) based on the data of the local heat flux calculated by the heat flux calculating unit 42. The heat flux visualization image is transmitted to the terminal device 24 and displayed on the display of the terminal device 24. This allows the user to easily check various phenomena occurring in the heating furnace 2 (for example, the occurrence of coking or film boiling on the heating pipe 12) based on the heat flux visualization image. Data related to the heat flux visualization image generated by the heat flux distribution generating unit 44 is stored in the storage unit 32 as heat flux image data 55.

[0077] Note that it is preferable that local heat fluxes at a larger number of target points are used when the heat flux distribution generation unit 44 generates a heat flux visualization image. Therefore, the control unit 31 acquires temperature measurement data of the thermographer 22 (i.e., the temperature distribution of the heating pipe 12 in a predetermined measurement area) corrected using the corrected ambient temperature, and can acquire the temperature in the temperature distribution as the target point temperature. This enables the control unit 31 to calculate the local heat flux for a larger number of locations (locations on the outer surface of the heating pipe 12 other than the target points measured by the two-color thermometer 23) based on the target point temperatures acquired by measurement with the thermographer 22 and the corresponding ambient temperatures.

[0078] With the above-described configuration, the control unit 31 can execute a process for acquiring the heat flux of the heating pipes 12 in the heating furnace 2 (hereinafter referred to as a heat flux acquisition process).

[0079] The storage unit 32 can be configured by hardware such as storage (an example of a storage device) for storing data and information required for the heat flux acquisition process by the heat flux acquisition device 4 as described above.

[0080] The communication unit 33 may be configured by hardware including an antenna, a communication circuit, etc., for the heat flux acquisition device 4 to communicate with the terminal device 24, etc. via the communication network 5. The control unit 31 may also function as a communication control unit that controls communication between the communication unit 33 and the terminal device 24, etc.

[0081] The heat flux acquisition device 4 is composed of a computer such as a server equipped with known hardware. The heat flux acquisition device 4 is appropriately equipped with known hardware such as one or more processors, memory, display, input device, network interface, and storage. At least some of the functions of each unit 41-44 in the control unit 31 can be realized by the processor executing a predetermined control program. Note that in the heat flux acquisition system 1, at least some of the functions of the heat flux acquisition device 4 described above may be realized by multiple computers working together. Furthermore, at least some of the functions of the heat flux acquisition device 4 may be included in the terminal device 24.

[0082] Next, the details of the heat flux acquisition method using the heat flux acquisition system 1 will be described with reference to the schematic diagram of the inside of the heating furnace 2 shown in FIG.

[0083] As shown in Figure 3, nine areas A1-A9 in which heating tubes 12 are arranged are defined within the heating furnace 2. Strictly speaking, the heating tubes 12 are arranged in a three-dimensional space, but for the sake of convenience, they are assumed to be arranged in planar rectangular areas A1-A9 observed from one side of the heating furnace 2 (e.g., the side from the observation window). The heating tubes 12 extend from top to bottom while reciprocating left and right within the heating furnace 2. The fluid to be heated flows into the heating tube 12 through an inlet 12A, flows through the heating tube 12, is heated, and then flows out through an outlet 12B of the heating tube 12. The heating tube 12 and the fluid to be heated flowing through it are heated by the flame or exhaust gas of a burner arranged below.

[0084] In FIG. 3, the portions of the heating tube 12 in areas A1-A9 (hereinafter referred to as segments G １ -G ９ The outer surface area (i.e., the surface area of ​​the outer periphery) of each １ -S ９ In addition, the segment G of the heating tube 12 is set to １ -G ９ The environmental temperatures of the areas A1-A9 corresponding to Ｂ１ -T Ｂ９ In addition, segment G １ -G９ In each segment G １ -G ９ By dividing the area into a plurality of segments in the longitudinal direction, a plurality of sub-segments can be set for each segment. In FIG. 3, as an example of the sub-segments, eight sub-segments G1 are set for the segment G1 in the area A1. １－１ -G １－８ The target point P of the heating pipe 12 is １－１ -P １－８ For example, the subsegment G １－１ -G １－８ The target point P １－１ -P １－８ The target point temperature T Ｒ１－１ -T Ｒ１－８ is the subsegment G １－１ -G １－８ The representative temperature is set for each of the other areas A2-A9. Target points and sub-segments are set for each of the other areas A2-A9 in the same manner as for area A1.

[0085] The number and size (i.e., range) of the areas, segments, and sub-segments set for the heating furnace 2 are not limited to those shown in Fig. 3 and may be modified in various ways. Also, sub-segments may be omitted.

[0086] As shown in FIG. 4, in the heat flux acquisition process by the heat flux acquisition device 4, first, each target point P １－１ -P １－８ , the target point temperature T measured by the two-color thermometer 23 Ｒ１－１ -T Ｒ１－８ is acquired (ST101).

[0087] Next, the heat flux acquisition device 4 acquires the heat flux at each target point P １－１ -P １－８ The environmental temperature T obtained by tuning during measurement using the thermography 22 described later Ｂ１ (an example of estimated environmental temperature) is acquired (ST102).

[0088] Then, the heat flux acquisition device 4 acquires the heat flux at each target point P １－１ -P １－８Regarding the target point temperature T Ｒ１－１ -T Ｒ１－８ and the environmental temperature T Ｂ１ Based on this, each local heat flux q １－２ -q １－８ For example, the target point P １－１ Local heat flux q in １－１ [W / m ２ ] can be calculated from the following formula (1): １－１ = ε σ (T Ｂ１ ４ -T Ｒ１－１ ４ ) ... (1) where the symbols are as follows: T Ｒ１－１ : Target point P of the heating pipe 12 １－１ External surface temperature [K] T Ｂ１ : Environmental temperature of area A1 [K] ε: Emissivity of heating tube 12 σ: Stefan-Boltzmann constant (5.67 × 10 －８ [W / (m ２ ・K ４ )])

[0089] In addition, other target points P １－２ -P １－８ Local heat flux q in １－２ -q １－８ [W / m ２ ], the target point P １－１ Local heat flux q in １－１ can be calculated in the same way.

[0090] The heat flux acquisition device 4 can acquire the local heat flux over the entire heating pipe 12 by repeatedly executing the same processes as steps ST101 to ST103 described above for the other areas A2 to A9.

[0091] Here, the acquisition of the environmental temperature in step ST102 will be described. The radiant energy E(T) [J] of the infrared rays incident on the thermography 22 in measuring the temperature of the heating pipe 12 can be expressed by the following equation (2): E(T) = ε E(T Ｒ )+(1-ε)・E(T Ｂ ) ... (2) where the symbols are as follows: E(TＲ ): Radiant energy [J] E(T Ｂ ): Environmental reflected energy [J] on the outer surface of the heating pipe 12 T: Temperature reading [K] T by the thermograph 22 Ｒ : outer surface temperature of the heating tube 12 (i.e., true temperature) [K] T Ｂ : Environmental temperature [K] ε: Emissivity of heating tube 12

[0092] Outer surface temperature T of heating tube 12 Ｒ The measurement value of the two-color thermometer 23 can be used as the temperature measurement value. The two-color thermometer 23 (i.e., a wavelength distribution type radiation thermometer) is independent of the emissivity and the environmental conditions, and therefore can provide more accurate measurements than the measurement by the thermograph 22.

[0093] In tuning the thermography 22 for measurement, the user may compare the temperature reading T from the thermography 22 at a certain target point with the measurement T from the two-color thermometer 23 at the same target point. Ｒｍ and the environmental temperature T Ｂ can be set.

[0094] For example, for area A1, the environmental temperature T Ｂ１ is set.

[0095] Here, each symbol is as follows: T １－ｊ : Temperature indication value [K] of the target point by the thermograph 22 T Ｒ１－ｊ : Temperature of target point where j (= 1, 2, ..., 8) is the sub-segment number.

[0096] In addition, the environmental temperature T Ｂ２ -T Ｂ９ Regarding the environmental temperature T Ｂ１ The set environmental temperature T Ｂ１ -T Ｂ９ is input to the terminal device 24 and transmitted to the heat flux acquisition device 4.

[0097] Such tuning during measurement by the thermography 22 may be performed automatically without user operation. In this case, the thermography 22 may, for example, transmit the target point temperature T measured by the two-color thermometer 23 through short-distance communication with the two-color thermometer 23. Ｒｉ－ｊ can be obtained.

[0098] The local heat flux (for example, the local heat flux q １－２ -q １－８ [W / m ２ ]) is a heat flux value at a predetermined portion in the circumferential direction of the heating tube 12 made of a circular tube. On the other hand, in the heating tube 12, the heat flux and temperature in the circumferential direction may differ depending on the relative position of the heating tube 12 with respect to the flame of the combustion device 13.

[0099] The heat flux distribution in the circumferential direction of the tube can be determined based on the tube diameter, the tube spacing, and the arrangement, for example, in accordance with API (American Petroleum Institute) 530. Similarly, by appropriately setting the ratio to the local heat flux obtained in ST103, the heat flux (i.e., three-dimensional heat flux distribution) at each part in the circumferential direction of the heating tube 12 can be obtained. In addition, the average local heat flux in the circumferential direction in a predetermined subsegment can be obtained using, for example, the flame front ratio γ1, and the average local heat flux in the subsegment G of the area A1 can be obtained using, for example, the flame front ratio γ1. １－１ If the flame surface ratio at is γ1, the average local heat flux q １－１ａｖｅ , q １－１ / γ1.

[0100] Next, a first modified example of the heat flux acquisition process shown in Fig. 4 will be described with reference to Fig. 5. In the first modified example, matters not specifically mentioned below are the same as those in the heat flux acquisition method described above.

[0101] In the heat flux acquisition process according to the first modified example, as shown in Fig. 5, steps ST201 to ST203 similar to steps ST101 to ST103 in Fig. 4 are executed. As a result, the local heat flux over the entire heating pipe 12 (i.e., in areas A1 to A9) is acquired.

[0102] Next, the heat flux acquisition device 4 calculates the estimated average heat flux (ST204). In calculating the estimated average heat flux, the heat flux acquisition device 4 first calculates the estimated average heat flux for each sub-segment G １－１ -G １－８ External surface area S １－１ -S １－８ and the corresponding target points P １－１ -P １－８ Local heat flux q with respect to １－１ -q １－８ The estimated segment-averaged heat flux q for segment G1 is calculated based on the weighted average of １total where q １－１ -q １－８ The value of may be the average local heat flux in the circumferential direction described above.

[0103] More specifically, the estimated segment average heat flux q for segment G1 １total [W / m ２ ] can be calculated from the following formula (4).

[0104] Here, each symbol is as follows: q １－ｊ : Target point P １－ｊ Local heat flux [W / m ２ ] S １－ｊ : Subsegment G １－ｊ External surface area [m ２ ] where j (= 1, 2, ..., 8) is the sub-segment number.

[0105] The estimated segment average heat flux q for segments G2-G9 in areas A2-A9 ２total -q ９total For the segment G1, the estimated segment average heat flux q １total can be calculated in the same way.

[0106] The heat flux acquisition device 4 calculates the estimated segment average heat flux q １total -q ９total The average value of the estimated average heat flux q ＡＶＧ It can be calculated as:

[0107] Next, the heat flux acquisition device 4 calculates the actual average heat flux (ST205). The heat flux acquisition device 4 calculates the actual average heat flux q ＲＥＡＬ [W / m ２ ] can be calculated. ＲＥＡＬ =M Ｆ ・(H ＯＵＴ -H ＩＮ ) / S ＡＬＬ ... (5) where the symbols are as follows: M Ｆ : Mass flow rate of heated fluid [kg / s] H ＩＮ : specific enthalpy [J / kg] of the heated fluid flowing into the heating pipe 12 H ＯＵＴ : specific enthalpy [J / kg] of the heated fluid flowing out of the heating tube 12 S ＡＬＬ : total surface area of ​​the heating tube 12 (= S １ +S ２ +...+S ９ ) [m ２ ]

[0108] Next, the heat flux acquisition device 4 calculates the estimated average heat flux q of equation (4) ＡＶＧ The actual average heat flux q in equation (5) ＲＥＡＬ In other words, the heat flux acquisition device 4 corrects the environmental temperature acquired in ST202 so that the estimated average heat flux q ＡＶＧ is the actual average heat flux q ＲＥＡＬ The corrected ambient temperature is calculated so that it matches the

[0109] Furthermore, the heat flux acquisition device 4 calculates a corrected local heat flux based on the calculated corrected ambient temperature, similar to step ST202 (ST207).

[0110] In this way, the heat flux acquisition device 4 can acquire the local heat flux over the entire heating tube 12 .

[0111] <Alternative Method 1> Next, an alternative method 1 in which the heat flux acquisition process is partially modified will be described. Matters of alternative method 1 that are not specifically mentioned below are the same as steps ST201 to ST207 in the heat flux acquisition process described above.

[0112] In Alternative Method 1, the heat flux acquisition device 4 acquires the heat flux from the segment G in step ST202. １ -G ９ (here, segment G １ ) is the representative segment, and other segments (here, segment G ２ -G ９ ) can be set as a subordinate segment. Furthermore, the heat flux acquisition device 4 can set the subordinate segment G ２ -G ９ The environmental temperatures T Ｂ２ -T Ｂ９ and representative segment G １ The corresponding environmental temperature T Ｂ１ The temperature ratios set can be stored in the storage unit 32 as part of the environmental temperature data 53.

[0113] For example, the environmental temperature T Ｂ２ and the environmental temperature T corresponding to the representative segment G1 Ｂ１ Temperature ratio α Ｂ２ can be expressed as the ratio of their fourth powers as in the following equation (6): Ｂ２ ４ = α Ｂ２ ・T Ｂ１ ４ ...(6)

[0114] In addition, other subordinate segments G ３ -G ９ The environmental temperatures T Ｂ３ -T Ｂ９ and the environmental temperature T Ｂ１ Temperature ratio α Ｂ３ -α Ｂ９ Regarding the temperature ratio α for the subordinate segment G2, Ｂ２ can be expressed similarly as:

[0115] As a result, the heat flux acquisition device 4 obtains the temperature ratio α Ｂ２ -α Ｂ９ After acquiring the temperature, even if the operating conditions of the heating furnace 2 are changed, the environmental temperature T Ｂ１ By acquiring (or calculating) the environmental temperature T Ｂ１to the environmental temperature T of the subordinate segments G2-G9 Ｂ２ -T Ｂ９ This reduces the load of the heat flux acquisition device 4 in calculating the environmental temperature (and therefore the local heat flux).

[0116] To calculate the local heat flux when the operating conditions are changed using the above-mentioned environmental temperature ratio, the environmental temperature of the subordinate segment is calculated from the environmental temperature of the representative segment and the environmental temperature ratio obtained from the operating data, and the heat flux at each target point is obtained using the target point temperatures and the environmental temperatures at each target point of all segments.

[0117] In this case, the target point temperature may be a value measured by a temperature sensor, or may be a value calculated by a separate calculation.

[0118] Next, a method for calculating the target point temperature value will be described.

[0119] Local heat flux q at the target point (segment i, subsegment j) ｉ－ｊ is the outer surface temperature of the heating pipe 12 at the target point (i.e., the target point temperature) T Ｒｉ－ｊ [K] and inner surface temperature T Ｉｉ－ｊ [K] and thermal resistance R ｉ―ｊ [m ２ .K / W] can be expressed as the following equation (7).

[0120] q ｉ－ｊ = (1 / R ｉ－ｊ )・(T Ｒｉ－ｊ -T Iｉ－ｊ ) ... (7) where R ｉ－ｊ =R Ｗｉ－ｊ +R Ｒｉ－ｊ +R Ｉｉ－ｊ + (1 / h ｉ－ｊ ) and each symbol is as follows. ｉ－ｊ can be obtained based on the API 530. Ｗｉ－ｊ : Thermal resistance of heating tube = t Ｗｉｊ / λ[m 2 ・K / W] (where t Ｗｉｊ : pipe thickness [m], λ: pipe thermal conductivity [W / (m・K)]) R Ｒｉ－ｊ: Thermal resistance of scale attached to the outer surface of the heating tube [m 2 ・K / W] R Ｉｉ－ｊ : Thermal resistance of scale attached to the inner surface of the heating tube [m 2 ・K / W] h ｉ－ｊ : Heat transfer coefficient of the flow inside the pipe [W / (m・K)]

[0121] Inner surface temperature T Ｉｉ－ｊ [K] corresponds to the temperature of the heated fluid in the pipe at the target point, and can be expressed as the following equation (8).

[0122] Here, each symbol is as follows: q ｉ－ｊ : Local heat flux [W / m2] T first : Temperature at the time of inflow of heated fluid (initial temperature) [K] S ｉ－ｊ : Surface area of ​​the pipeline to the target point [m ２ ] γ: Flame surface ratio M Ｆ : Mass flow rate of heated fluid [kg / s] Cp: Specific heat [J / (kg・K)]

[0123] Based on the above equations (1) and (7), the target point P near the inlet of the heating tube 12 １－１ For (i=1, j=1), the following equation (9) holds: I１－１ =T first Let's say.

[0124]

[0125] As a result, T Ｒ１－１ (The target point P of the heating pipe 12 １－１ The outer surface temperature [K] at the target point P １－１ It can be calculated in the same way.

[0126] Alternative Method 2 Next, an alternative method 2 in which the heat flux acquisition process is partially modified will be described. Matters not specifically mentioned below regarding Alternative Method 2 are the same as those in the heat flux acquisition process described above (see FIG. 5).

[0127] In Alternative Method 2, the past operating conditions of the heating furnace 2 and the environmental temperatures T Ｂ１ -T Ｂ９The above data is prepared, and the heat flux acquisition device 4 constructs a machine learning model using the prepared data as training data. The constructed machine learning model is stored in the storage unit 32 of the heat flux acquisition device 4. Although not particularly limited, a known algorithm such as a neural network can be used for the machine learning model.

[0128] The operating conditions of the heating furnace 2 include combustion conditions (e.g., fuel composition, fuel pressure, fuel flow rate, etc.) in the heating furnace 2. The operating conditions may also include operating conditions of each burner (fuel supply (injection) pressure, air volume, etc.) and conditions inside the furnace (furnace temperature, flame shape and size).

[0129] The heat flux acquisition device 4 acquires data on the current operating conditions (or planned operating conditions) of the heating furnace 2, and calculates the environmental temperature T Ｂ１ -T Ｂ９ The data can be estimated.

[0130] In Alternative Method 2, the machine learning model may be stored in a server or the like that can communicate with the heat flux acquisition device 4 via the communication network 5. Alternatively, data on past operating conditions of the heating furnace 2 and on each local heat flux under each operating condition may be prepared, and the heat flux acquisition device 4 may construct the machine learning model using this data as training data. Alternatively, the heat flux acquisition device 4 may use a machine learning model constructed by a computer such as another information processing device.

[0131] Although the description of the specific embodiment has been completed above, the present invention is not limited to the above embodiment and its modifications, and can be implemented in a wide variety of modifications. The components of the heat flux acquisition device, heat flux acquisition system, and heat flux acquisition method shown in the above embodiment are not necessarily all essential, and at least those skilled in the art can select appropriate components as long as they do not deviate from the scope of the present invention.

[0132] 1: Heat flux acquisition system 2: Heating furnace 3: On-site equipment 4: Heat flux acquisition device 5: Communication network 11: Casing 12: Heating pipe 12A: Inlet 12B: Outlet 13: Combustion device 14: Upper area 15: Lower area 21: Measuring instrument 22: Thermography 23: Two-color thermometer 24: Terminal device 31: Control unit 32: Memory unit 33: Communication unit 41: Data acquisition unit 42: Heat flux calculation unit 43: Environmental temperature correction unit 44: Heat flux distribution generation unit 51: Heating furnace data 52: Heating pipe temperature data 53: Environmental temperature data 54: Heat flux data 55: Heat flux image data A1-A9: Area G １ -G ９ : Segment G １－１ -G １－８ : Subsegment

Claims

1. A heat flux acquisition device for acquiring a heat flux of an object in a heating furnace, a processor that executes processing to acquire the heat flux of the object; The processor: acquiring a target point temperature measured by a temperature sensor at a target point on the outer surface of the object; Obtaining an environmental temperature corresponding to the target point; calculating a local heat flux for the target point based on the target point temperature and the corresponding environmental temperature; The heating furnace is a tubular heating furnace, The heat flux acquisition device, wherein the object includes a heating tube of the tube furnace.

2. The heat flux acquisition device according to claim 1, wherein the local heat flux is calculated based on energy radiated toward the object, which is calculated based on the ambient temperature, and energy radiated from the object, which is calculated from the object point temperature.

3. The heat flux acquisition device according to claim 1 or 2, wherein the environmental temperature is an estimated environmental temperature estimated based on the temperature of the corresponding target point in thermography measurement of the target point.

4. the environmental temperature is a corrected environmental temperature obtained by calculation, the heating pipe has one or more segments and a plurality of target points set for each of the segments; 2. The heat flux acquisition device according to claim 1, wherein the corrected ambient temperature is calculated based on at least the target point temperatures measured by the temperature sensors for each of the target points, the heat quantity of the heated fluid flowing into the heating pipe, and the heat quantity of the heated fluid flowing out of the heating pipe.

5. The processor: acquiring the temperature of each of the target points; obtaining an estimated environmental temperature in the furnace corresponding to each of the segments, the estimated environmental temperature being estimated based on the corresponding target point temperatures; calculating an estimated local heat flux for each of the target points based on the target point temperature and the corresponding estimated ambient temperature; calculating an estimated segment average heat flux or an estimated segment heat input amount for each of the segments based on the estimated local heat flux, and acquiring an estimated average heat flux or an estimated heat input amount for the heating pipe based on the estimated segment average heat flux or the estimated segment heat input amount; calculating an actual average heat flux or an actual heat input amount related to the heating pipe based on a heat amount of the heated fluid flowing into the heating pipe and a heat amount of the heated fluid flowing out of the heating pipe; 5. The heat flux acquisition device according to claim 4, wherein the corrected ambient temperature is calculated by correcting the estimated ambient temperature so that the estimated average heat flux coincides with the actual average heat flux or so that the estimated heat input coincides with the actual heat input.

6. Each of the segments includes sub-segments set corresponding to the respective target points, The processor: The heat flux acquisition device according to claim 5 , wherein the estimated segment average heat flux for each of the segments is calculated based on a weighted average using the surface area of ​​each of the sub-segments as a weight of the local heat flux for the corresponding target point.

7. the heating tube has a plurality of segments including one representative segment and subordinate segments other than the representative segment, the estimated environmental temperature of the subordinate segment is expressed using a temperature ratio to the estimated environmental temperature of the representative segment; The processor: calculating a corrected ambient temperature of the representative segment so that the estimated average heat flux coincides with the actual average heat flux or so that the estimated heat input coincides with the actual heat input; The heat flux acquisition device according to claim 6 , further comprising: calculating a corrected ambient temperature of the subordinate segment based on the corrected ambient temperature of the representative segment and the temperature ratio.

8. The heat flux acquisition device according to claim 7 , further comprising a storage device that stores the temperature ratio between the estimated environmental temperature of the subordinate segment and the estimated environmental temperature of the representative segment.

9. The processor: acquiring the temperature of each of the target points; acquiring the corrected environmental temperature of the representative segment and the corrected environmental temperature of the subordinate segment; The heat flux acquisition device according to claim 8 , wherein a local heat flux for the target point is calculated based on the target point temperature and the corresponding corrected environmental temperatures of the representative segment and the corresponding corrected environmental temperatures of the subordinate segment.

10. The heat flux acquisition device of claim 9 , wherein the processor further calculates a target point temperature for the target point based on the corrected ambient temperature of the representative segment and the corrected ambient temperature of the subordinate segment.

11. Further comprising a storage device; The processor further comprises: calculating an actual average heat flux related to the heating pipe based on a heat quantity of the heated fluid flowing into the heating pipe and a heat quantity of the heated fluid flowing out of the heating pipe; The heat flux acquisition device according to claim 1 , further comprising: a heat flux ratio between the actual average heat flux and the local heat flux calculated; and the heat flux ratio stored in the storage device.

12. The processor: acquiring the heat flux ratio stored in the storage device; calculating an actual average heat flux related to the heating pipe based on a heat quantity of the heated fluid flowing into the heating pipe and a heat quantity of the heated fluid flowing out of the heating pipe; The heat flux acquisition device according to claim 11 , wherein the local heat flux is acquired based on the heat flux ratio and the actual average heat flux.

13. Further comprising a storage device; The processor: storing the operating conditions of the heating furnace and the environmental temperature under the operating conditions in the storage device; constructing a machine learning model that inputs the operating conditions stored in the storage device and outputs the environmental temperature; The heat flux acquisition device according to claim 1 .

14. The processor: inputting new operating conditions of the heating furnace into the machine learning model to obtain the environmental temperature; calculating a local heat flux based on the acquired environmental temperature and a target point temperature on the outer surface of the object; The heat flux acquisition device according to claim 13 .

15. The heat flux acquisition device according to claim 13 or 14, wherein the operating conditions include combustion conditions of the heating furnace and operating conditions of burners in the heating furnace.

16. The processor: The heat flux acquisition device according to claim 1 , wherein an image visualizing the distribution of the local heat flux is generated.

17. the heating pipe has one or more segments and a plurality of target points set for each segment; The heat flux acquisition device according to claim 5 , wherein the processor acquires a temperature distribution of the object measured by thermography using the estimated environmental temperature.

18. The processor: The heat flux acquisition device according to claim 17 , wherein a temperature in the temperature distribution of the object is acquired as the object point temperature.

19. The heating pipe has one or more segments and a plurality of target points respectively set for each of the segments; the environmental temperature is set for each of the segments, The heat flux acquisition device according to claim 1 , wherein the local heat flux is calculated for each of the segments based on the target point temperature of the segment and the environmental temperature of the segment.

20. A heat flux acquisition method for acquiring a heat flux of an object in a heating furnace, comprising: The computer acquiring a target point temperature measured by a temperature sensor at a target point on the outer surface of the object; Obtaining an environmental temperature corresponding to the target point; calculating a local heat flux for the target point based on the target point temperature and the corresponding environmental temperature; The heating furnace is a tubular heating furnace, The heat flux acquisition method, wherein the object includes a heating tube of the tube heating furnace.