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

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

[Technical Field]

[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. [Background technology]

[0002] Conventionally, a method for estimating the outer surface temperature of a coil in an ethylene production and decomposition furnace is known that reflects the temperature of areas with relatively higher temperatures within the area to be imaged (see Patent Document 1). In this conventional method, a color video camera that outputs the brightness at each light-receiving pixel for each RGB wavelength, a monochrome video camera that measures the brightness at a single wavelength of 1 μm to less than 3 μm, or a two-sensor camera that measures the ratio of the brightness at a first wavelength and a second wavelength of 1 μm to less than 3 μm is used as the imaging camera for imaging the area to be imaged of the coil.

[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, in order to determine the net radiant heat flux on the exterior surface of a building, an infrared thermographic image is taken and the obtained image is analyzed. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 7111583 [Patent Document 2] Chinese Patent Application Publication No. 113970388 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Incidentally, in heating furnaces used as plant equipment, the heat flux related to heating tubes, etc., is an important indicator related 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 cameras or thermography are known, as described in the prior art documents 1 and 2 above, there is no widespread method for easily obtaining the heat flux (i.e., local heat flux) at a desired location of an object inside a heating furnace.

[0007] In view of the above background, the present invention aims 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. [Means for solving the problem]

[0008] To solve the above problems, one aspect of the present invention is a heat flux acquisition device (4) for acquiring the heat flux of an object (12) inside a heating furnace (2), comprising a processor that performs processing for acquiring the heat flux of the object, wherein the processor acquires the temperature of a target point measured by a temperature sensor (23) for a target point on the outer surface of the object, acquires the ambient temperature corresponding to the target point, and calculates the local heat flux for the target point based on the target point temperature and the corresponding ambient temperature.

[0009] According to this embodiment, the local heat flux of an object inside a heating furnace can be easily obtained.

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

[0011] According to this embodiment, the local heat flux of an object inside a heating furnace can be easily calculated based on the ambient temperature and the temperature of the target point.

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

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

[0014] In the above embodiment, the ambient temperature is preferably an estimated ambient temperature estimated based on the temperature of the corresponding target point in the measurement of the target point by thermography (22).

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

[0016] In the above embodiment, the ambient temperature is a corrected ambient temperature determined by calculation, and the heating tube has one or more segments (G1-G9) and a plurality of target points (P) set for each of the segments. 1-1 -P 1-8 The corrected ambient temperature is preferably calculated based on at least the target point temperature measured by the temperature sensor for each of the target points, the amount of heat in the heated fluid flowing into the heating tube, and the amount of heat in the heated fluid flowing out of the heating tube.

[0017] According to this embodiment, the accuracy of the ambient temperature can be improved by obtaining an ambient temperature corrected based on the heat quantity of the heated fluid (i.e., a corrected ambient temperature).

[0018] In the above embodiment, the processor may obtain the temperature of each target point, obtain an estimated ambient temperature in the furnace corresponding to each segment, which is estimated based on the corresponding temperature of each target point, calculate an estimated local heat flux for each target point based on the temperature of each target point and the corresponding estimated ambient temperature, calculate an estimated segment average heat flux or estimated segment heat input for each segment based on the estimated local heat flux, obtain an estimated average heat flux or estimated heat input for the heating tube 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 tube based on the heat amount of the heated fluid flowing into the heating tube and the heat amount of the heated fluid flowing out of the heating tube, and calculate the corrected ambient temperature by correcting the estimated ambient temperature so that the estimated average heat flux matches the actual average heat flux, or the estimated heat input matches the actual heat input.

[0019] According to this embodiment, the accuracy of the ambient temperature can be improved by calculating a corrected ambient temperature (i.e., a corrected ambient temperature) based on the heat flux or heat input of each segment (i.e., estimated segment heat flux or estimated segment heat input) based on the temperature of each target point and the corresponding estimated ambient temperature, 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 embodiment, each segment includes a subsegment (G) set to correspond to each of the target points. 1-1 -G 1-8 ) is included, and the processor includes the surface area (s) of each subsegment. 1-1 -s 1-8 The estimated segment-average heat flux for each segment is calculated based on a weighted average in which the respective local heat fluxes for the target points are used as weights.

[0021] According to this embodiment, by considering the surface area of ​​each sub-segment set to correspond to each target point, the heat flux for each segment can be obtained with high accuracy.

[0022] In the above embodiment, the heating tube has a plurality of segments, including one representative segment and dependent segments other than the representative segment, the estimated ambient temperature of the dependent segment is expressed using a temperature ratio to the estimated ambient temperature of the representative segment, and the processor may calculate the corrected ambient temperature of the representative segment and calculate the corrected ambient temperature of the dependent segment based on the corrected ambient temperature of the representative segment and the temperature ratio.

[0023] According to this embodiment, the corrected ambient temperature of the dependent segment is calculated based on the corrected ambient temperature of the representative segment, making it easy to obtain the corrected ambient temperature of each segment.

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

[0025] According to this embodiment, it becomes easier to utilize the temperature ratio between the estimated ambient temperature of the dependent segment and the estimated ambient temperature of the representative segment.

[0026] In the above embodiment, 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 dependent 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 dependent segment.

[0027] According to this embodiment, by utilizing previously acquired temperature ratios, even if the operating conditions of the heating furnace 2 are changed, the corrected ambient temperature of each dependent segment can be easily calculated from the corrected ambient temperature of the representative segment, thereby reducing the processing load for calculating the local heat flux for each target point.

[0028] In the above embodiment, the processor may further calculate the target point temperature based on the corrected ambient temperature of the representative segment and the corrected ambient temperature of the dependent segment.

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

[0030] In the above embodiment, the device further comprises a memory device (32), wherein the processor further calculates the actual average heat flux for the heating tube based on the amount of heat of the fluid to be heated flowing into the heating tube and the amount of heat of the fluid to be heated flowing out of the heating tube, calculates the heat flux ratio between the actual average heat flux and the local heat flux, and stores the heat flux ratio in the memory device.

[0031] According to this embodiment, the use of the heat flux ratio between the actual average heat flux and the local heat flux becomes easier.

[0032] In the above embodiment, the processor may obtain the heat flux ratio stored in the memory device, calculate the actual average heat flux for the heating tube based on the amount of heat of the fluid to be heated flowing into the heating tube and the amount of heat of the fluid to be heated flowing out of the heating tube, and obtain the local heat flux based on the heat flux ratio and the actual average heat flux.

[0033] According to this embodiment, the processing load for calculating local heat flux is reduced by utilizing previously acquired heat flux ratios. In particular, it has the advantage of eliminating the need to measure the target point temperature of the heating tube, and also eliminating the need to acquire and correct for ambient temperature.

[0034] In the above embodiment, the processor may further include a memory device, store the operating conditions of the heating furnace and the ambient temperature under those operating conditions in the memory device, and construct a machine learning model that takes the operating conditions stored in the memory device as input and outputs the ambient temperature.

[0035] According to this embodiment, the ambient temperature corresponding to the current operating conditions (or planned operating conditions) can be accurately obtained using a machine learning model constructed based on past operating conditions of the heating furnace and the ambient temperature under those operating conditions.

[0036] In the above embodiment, the processor may input new operating conditions for the heating furnace into the machine learning model to obtain the ambient temperature, and calculate the local heat flux based on the obtained ambient temperature and the temperature of a target point on the outer surface of the object.

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

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

[0039] According to this embodiment, ambient temperature (and consequently local heat flux) can be accurately obtained using appropriate operating conditions.

[0040] In the above embodiment, the temperature sensor may include a wavelength-distributed radiation thermometer.

[0041] According to this embodiment, even with non-contact measurement of the object to be measured, the temperature of the target point can be obtained with high accuracy.

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

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

[0044] In the above embodiment, the heating tube has one or more segments (G1-G9) and a plurality of target points set for each segment, and the processor may acquire the temperature distribution of the target object measured by thermography (32) using the estimated ambient temperature.

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

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

[0047] This embodiment offers greater flexibility in setting the target point of an object. It also has the advantage of easily acquiring the target point temperature over a wide area of ​​the object.

[0048] To solve the above problems, one aspect of the present invention is a heat flux acquisition system including the heat flux acquisition device, comprising a wavelength distribution type radiation thermometer (23) included in the temperature sensor and a thermograph (22) for acquiring the ambient temperature.

[0049] According to this embodiment, the local heat flux of an object inside a heating furnace can be easily obtained.

[0050] To solve the above problems, one aspect of the present invention is a heat flux acquisition method for acquiring the heat flux of an object (12) inside a heating furnace (2), wherein a computer (4) acquires the temperature of a target point measured by a temperature sensor (12) at a target point on the outer surface of the object, acquires the ambient temperature corresponding to the target point, and calculates the local heat flux for the target point based on the target point temperature and the corresponding ambient temperature.

[0051] According to this embodiment, the local heat flux of an object inside a heating furnace can be easily obtained. [Effects of the Invention]

[0052] According to the above embodiment, the local heat flux of an object inside a heating furnace can be easily obtained. [Brief explanation of the drawing]

[0053] [Figure 1] Overall configuration diagram of the heat flux acquisition system 1 according to this embodiment. [Figure 2] Block diagram of heat flux acquisition device 4 [Figure 3] Schematic diagram showing an example of the configuration inside heating furnace 2. [Figure 4] Flowchart showing the process of acquiring heat flux using the heat flux acquisition device 4. [Figure 5] Flowchart showing the first modified example of the heat flux acquisition process shown in Figure 4. [Figure 6] Flowchart showing a second modified example of the heat flux acquisition process shown in Figure 4. [Modes for carrying out the invention]

[0054] Hereinafter, with reference to the drawings, 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.

[0055] As shown in Figure 1, the heat flux acquisition system 1 includes field equipment 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 within the heating furnace 2. The field equipment 3 and the heat flux acquisition device 4 can communicate with each other via a communication network 5 such as a LAN (Local Area Network) or the Internet. However, the field equipment 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 forms. Inside the casing 11 (i.e., inside the heating furnace 2), there is a heating tube 12 through which the fluid to be heated flows, and a combustion device 13 including a burner. The heating tube 12 is made of a cylindrical tube, but it may have other forms. The heating tube 12 is heated by the heat of the flame or combustion gas of the combustion device 13. Inside the heating furnace 2, there is an upper area 14 for heating (or preheating) the fluid to be heated, and a lower area 15 for heating the fluid heated in the upper area 14. Although not shown in the figures, there are also multiple viewing windows in appropriate places on the casing 11 (e.g., on the side walls) for observing the inside of the heating furnace 2.

[0057] In this embodiment, the heating tube 12, which is mainly heated by radiant heat transfer, is described as the target (i.e., object) for acquiring the heat flux within the heating furnace 2. However, the target for acquiring such heat flux is not limited to the heating tube 12, but may be other components within the heating furnace 2 (for example, the inner wall of the casing 11). Alternatively, for example, the slab in a heating furnace for slab heating may be used as the target for acquiring the heat flux.

[0058] The on-site equipment 3 includes measuring instruments 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 locations on the heating tube 12 (for example, at the inlet, outlet, and intermediate sections of the heating fluid in the heating tube 12). The measuring instruments 21 may include thermometers, flow meters, and pressure gauges 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 within a predetermined measurement area in a non-contact manner based on infrared radiation emitted from the heating tube 12 inside the heating furnace 2. The measurement by the thermograph 22 is performed through a viewing window of the heating furnace 2. Multiple thermographs 22 may be provided to measure multiple measurement areas on the heating tube 12 simultaneously.

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

[0062] The terminal device 24 collects various measurement data measured with respect to the heating furnace 2. Such measurement data includes data measured by the measuring instrument 21 for the heated fluid, the thermograph 22, and the two-color thermometer 23. Furthermore, the measurement data may include data obtained by performing predetermined calculations using the measured data (i.e., indirectly measured data). The terminal device 24 is communicably 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 can also store specification data of the heating furnace 2 and transmit this data to the heat flux acquisition device 4. The specification data of the heating furnace 2 includes data required for calculations to acquire heat flux by the heat flux acquisition device 4 (for example, data regarding the physical properties, size, and position of the heating tube 12). The terminal device 24 may also be used as a control device for controlling the operation of the heating furnace 2.

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

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

[0065] Next, we will explain the details of the heat flux acquisition device 4.

[0066] As shown in Figure 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, specification data, etc., 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 storage unit 32 as heating furnace data 51. The measurement data regarding the temperature of the heating tube 12 obtained by the thermograph 22 and the two-color thermometer 23 are stored in the storage unit 32 as heating tube temperature data 52. The measurement data regarding the ambient temperature (i.e., the temperature around the heating tube 12 inside the heating furnace 2) obtained by the thermograph 22 is stored in the storage unit 32 as ambient temperature data 53. Inside the heating furnace 2, the corresponding ambient temperature differs depending on the location of the heating tube 12 (for example, its relative position to the flame of the combustion device 13). As will be described later, the ambient temperature is measured indirectly 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 of the heating tube 12. The positions of measurement points by the thermograph 22 and the two-color thermometer 23 can also be determined by global coordinates (i.e., the measured temperature, etc., can be associated with global coordinates). However, for the position data within the heating furnace 2, coordinate data uniquely set for the heating furnace 2 may be used.

[0069] The heat flux calculation unit 42 calculates the local heat flux at the target points of the heating tube 12 (an example of estimated local heat flux) based on the heating tube temperature data 52 (here, the target point temperature of each target point) and the ambient temperature data 53 (here, the ambient temperature corresponding to each target point). Furthermore, as will be described later, the heat flux calculation unit 42 may also calculate the local heat flux based on the corrected ambient temperature. In addition, the heat flux calculation unit 42 can calculate the average heat flux for the entire heating tube 12 (hereinafter referred to as estimated average heat flux) based on the local heat fluxes at multiple target points. However, the estimated average heat flux does not necessarily have to be the heat flux for the entire heating tube 12, but may be the heat flux for a predetermined area of ​​the heating tube 12 (for example, segments G1-G9 described later).

[0070] The heat flux calculation unit 42 may calculate the total amount of heat input to the heating tube 12 (hereinafter referred to as the estimated average heat input) based on the heat input amounts at multiple target points, either instead of or together with the estimated average heat flux.

[0071] Furthermore, the heat flux calculation unit 42 can calculate the average heat flux for the entire heating tube 12 (hereinafter referred to as the actual average heat flux) based on the amount of heat in the fluid to be heated flowing into the heating tube 12 and the amount of heat in the fluid to be heated flowing out of the heating tube 12 (i.e., the amount of heat input to the fluid to be heated that has flowed through the heating tube 12). The actual average heat flux does not necessarily have to be the total heat flux for the heating tube 12, but may be the heat flux for a predetermined area of ​​the heating tube 12 (for example, segments G1-G9 described later).

[0072] The heat flux calculation unit 42 may calculate or estimate the total heat input to the heating tube 12 (hereinafter referred to as the actual average heat input) from the amount of heat input to the heated fluid that flowed through the entire heating tube 12, instead of, or together with, the actual average heat flux. Alternatively, the actual average heat input may be calculated or estimated from the sum of the amounts of heat input to the heated fluid that flowed through each region of the heating tube 12 including multiple target points (for example, segments G1-G9 described later).

[0073] The local heat flux, estimated average heat flux, estimated average heat input, and data related to the actual average heat flux and actual average heat input calculated by the heat flux calculation unit 42 are stored in the storage 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 this as 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 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 ambient temperature correction unit 43 obtains a corrected ambient temperature by correcting the ambient temperature received from the terminal device 24 based on the estimated average heat flux and the actual average heat flux. The corrected ambient temperature data calculated by the ambient temperature correction unit 43 is stored in the storage unit 32 as ambient temperature data 53. More specifically, when the ambient temperature correction unit 43 calculates a corrected ambient temperature, the ambient temperature already stored in the storage unit 32 is updated with that corrected ambient temperature. Alternatively, the ambient temperature correction unit 43 may obtain the corrected ambient temperature by correcting an initial value of the ambient temperature previously stored in the storage unit 32, instead of the ambient temperature received from the terminal device 24.

[0076] The heat flux distribution generation unit 44 generates an image (hereinafter referred to as a heat flux visualization image) that visualizes the distribution of local heat flux at multiple target points on the heating tube 12 by color scheme (i.e., color change) based on the local heat flux data calculated by the heat flux calculation 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 confirm various phenomena inside the heating furnace 2 (for example, the occurrence of coking or film boiling in the heating tube 12) based on the heat flux visualization image. The data related to the heat flux visualization image generated by the heat flux distribution generation unit 44 is stored in the storage unit 32 as heat flux image data 55.

[0077] Furthermore, in the generation of heat flux visualization images by the heat flux distribution generation unit 44, it is preferable to use local heat flux at a larger number of target points. Therefore, the control unit 31 can acquire temperature measurement data from the thermograph 22 corrected using the corrected ambient temperature (i.e., the temperature distribution of the heating tube 12 within a predetermined measurement area), and acquire the temperature in that temperature distribution as the target point temperature. As a result, the control unit 31 can calculate local heat flux for a larger number of locations (locations on the outer surface of the heating tube 12 other than the target points measured by the two-color thermometer 23) based on the target point temperatures acquired by the thermograph 22 measurement and the corresponding ambient temperatures.

[0078] With the configuration described above, the control unit 31 can perform a process to acquire the heat flux of the heating tube 12 inside the heating furnace 2 (hereinafter referred to as the heat flux acquisition process).

[0079] As described above, the memory unit 32 may be composed of hardware such as storage (an example of a memory device) for storing data and information necessary for the heat flux acquisition process by the heat flux acquisition device 4.

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

[0081] The heat flux acquisition device 4 consists of a computer such as a server equipped with known hardware. The heat flux acquisition device 4 appropriately includes one or more known hardware such as a processor, memory, display, input device, network interface, and storage. At least some of the functions of each part 41-44 in the control unit 31 can be realized by the processor executing a predetermined control program. In addition, 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 provided by the terminal device 24.

[0082] Next, the details of the heat flux acquisition method using the heat flux acquisition system 1 will be explained based on the schematic diagram of the inside of the heating furnace 2 shown in Figure 3.

[0083] As shown in Figure 3, nine areas A1-A9 are set up inside the heating furnace 2 where the heating tubes 12 are located. More precisely, the heating tubes 12 are arranged in a three-dimensional space, but for the sake of explanation, they are assumed to be arranged in planar rectangular areas A1-A9 that can be observed from one side of the heating furnace 2 (for example, the viewing window side). The heating tubes 12 extend from top to bottom, reciprocating from left to right inside the heating furnace 2. The fluid to be heated flows in from the inlet 12A of the heating tubes 12, flows through the heating tubes 12 and is heated, and then flows out from the outlet 12B of the heating tubes 12. The heating tubes 12 and the fluid flowing through them are heated by the flame or exhaust gas of a burner located below.

[0084] In Figure 3, the external surface area (i.e., the surface area of ​​the outer periphery) of the heating tube 12 in areas A1-A9 (hereinafter referred to as segments G1-G9, respectively) is set to S1-S9, respectively. The ambient temperature of areas A1-A9 corresponding to segments G1-G9 of the heating tube 12 is set to T B1 -T B9is set. Also, in segments G1 - G9, a plurality of sub - segments can be set for each of segments G1 - G9 by dividing each segment G1 - G9 in the longitudinal direction. In FIG. 3, as an example of sub - segments, eight sub - segments G 1-1 -G 1-8 are shown for the segment G1 in area A1. The target points P 1-1 -P 1-8 of the heating pipe 12, for example, can be set at the representative positions (e.g., the center in the longitudinal direction) of sub - segments G 1-1 -G 1-8 . Also, the target point temperature T 1-1 -T 1-8 of the target points P R1-1 -T R1-8 is the representative temperature of sub - segments G 1-1 -G 1-8 . For the other areas A2 - A9, target points and sub - segments are set in the same way as in area A1.

[0085] Note that the number and size (i.e., range) of areas, segments, and sub - segments set for the heating furnace 2 are not limited to those shown in FIG. 3, and various changes are possible. 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, for each target point P 1-1 -P 1-8 in area A1 that is the acquisition target of heat flux, the target point temperature T R1-1 -T R1-8 measured by the two - color thermometer 23 is acquired for each (ST101). <​​​​​​​​​​​​Subsequently, the heat flux acquisition device 4 acquires the heat flux from each target point P. 1-1 -P 1-8 Regarding the temperature T of the target point, R1-1 -T R1-8 and ambient temperature T B1 Based on this, each local heat flux q 1-2 -q 1-8 Calculate (ST103). For example, target point P 1-1 Local heat flux q 1-1 [W / m 2 ] can be found from the following equation (1). q 1-1 =ε·σ(T B1 4 -T R1-1 4 ) ···(1) Here, the symbols are as follows: T R1-1 : Target point P of the heating tube 12 1-1 Outer surface temperature [K] T B1 Ambient temperature in area A1 [K] ε: Emissivity of heating tube 12 σ: Stefan-Boltzmann constant (5.67 × 10⁻⁶) -8 [W / (m 2 ·K 4 )])

[0089] Note that there are other target points P. 1-2 -P 1-8 Local heat flux q 1-2 -q 1-8 [W / m 2 Regarding ], the target point P 1-1 Local heat flux q 1-1 It can be calculated in the same way.

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

[0091] Here, we will explain how to obtain the ambient temperature in step ST102 described above. The infrared radiation energy E(T)[J] incident on the thermograph 22 during the measurement of the temperature of the heating tube 12 can be expressed as shown in the following equation (2). E(T) = ε·E(T) R )+(1-ε)·E(T B ) ···(2) Here, the symbols are as follows: E(T R Radiant energy from heating tube 12 [J] E(T B ): Environmental reflected energy [J] at the outer surface of the heating tube 12 T: Temperature reading [K] from thermography 22 T R : The outer surface temperature (i.e., true temperature) of the heating tube 12 [K] T B :Environmental temperature [K] ε: Emissivity of heating tube 12

[0092] Outer surface temperature T of heating tube 12 R For this purpose, the measurement values ​​from the two-color thermometer 23 can be used. The two-color thermometer 23 (i.e., a wavelength-distributed radiation thermometer) does not depend on emissivity and environmental conditions, so it is possible to perform more accurate measurements compared to those of the thermograph 22.

[0093] When tuning measurements using the thermograph 22, the user sets the temperature reading T from the thermograph 22 at a certain target point to the measured value T from the two-color thermometer 23 at the same target point. Rm To make them match, the ambient temperature T B You can set this.

[0094] For example, for area A1, the ambient temperature T that minimizes the error e shown in equation (3) below is... B1 This will be set.

[0095]

number

[0096] Note that the ambient temperature T of other areas A2-A9 B2 -T B9 Regarding the ambient temperature T in area A1, B1 It can be set in the same way. The set ambient temperature T B1 -T B9 This is input to terminal device 24 and transmitted to heat flux acquisition device 4.

[0097] The tuning of the thermographic image 22 during measurement may be performed automatically without user intervention. In that case, the thermographic image 22 will, for example, communicate with the two-color thermometer 23 via short-range communication to obtain the target point temperature T measured by the two-color thermometer 23. Ri-j You can obtain it.

[0098] The local heat flux (for example, local heat flux q) obtained in step ST103 above 1-2 -q 1-8 [W / m 2 ]) is the heat flux value in a predetermined portion in the circumferential direction of the heating tube 12, which is made of a circular pipe. 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 with respect to the flame of the combustion device 13.

[0099] The circumferential heat flux distribution of the pipe can be determined based on, for example, the pipe diameter, pipe spacing, and arrangement in accordance with API (American Petroleum Institute) 530. Similarly, by appropriately setting the ratio with respect to the local heat flux obtained by ST103, the heat flux in each part in the circumferential direction in the heating pipe 12 (that is, the three-dimensional heat flux distribution) can be obtained. Further, the circumferential average local heat flux in a predetermined sub-segment can be obtained, for example, using the flame surface ratio γ1. When the flame surface ratio in the sub-segment G 1-1 in the area A1 is γ1, the average local heat flux q 1-1ave can be obtained as q 1-1 / γ1.

[0100] Next, referring to FIG. 5, a first modification of the heat flux acquisition process shown in FIG. 4 will be described. In the first modification, matters not particularly mentioned below are the same as those in the above-described heat flux acquisition method.

[0101] In the heat flux acquisition process according to the first modification, as shown in FIG. 5, steps ST201 - ST203 similar to steps ST101 - ST103 in FIG. 4 are executed. Thereby, the local heat flux is acquired over the entire heating pipe 12 (that is, in areas A1 - A9).

[0102] Next, the heat flux acquisition device 4 calculates an estimated average heat flux (ST204). In this calculation of the estimated average heat flux, the heat flux acquisition device 4 first, for area A1, based on the weighted average using the outer surface areas S 1-1 -S 1-8 of each sub-segment G 1-1 -G 1-8 as the weights for the local heat fluxes q 1-1 -q 1-8 corresponding to the target points P 1-1 -P [[ID=۳۳]] 1-8 calculates the estimated segment average heat flux q 1total for segment G1. Here, q 1-1 -q 1-8As the value, it is advisable to use the above-mentioned circumferential average local heat flux.

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

[0104] [Equation]] Here, each symbol is as shown below. q 1-j : Local heat flux [W / m 1-j for the target point P 2 S 1-j : Outer surface area [m 1-j of the sub-segment G 2 However, j (= 1, 2, ···, 8) is the sub-segment number.

[0105] Note that the estimated segment average heat fluxes q 2total -q 9total for segments G2 - G9 in areas A2 - A9 can also be obtained in the same way as the estimated segment average heat flux q 1total for segment G1.

[0106] The heat flux acquisition device 4 can calculate the average value of those estimated segment average heat fluxes q 1total -q 9total as the estimated average heat flux q AVG for the entire heating pipe 12.

[0107] Next, the heat flux acquisition device 4 calculates the actual average heat flux (ST205). The heat flux acquisition device 4 can calculate the actual average heat flux q REAL [W / m 2 from the following equation (5). q REAL = M F ·(H OUT - H IN ) / S​ALL ...(5) Here, the symbols are as follows: M F :Mass flow rate of heated fluid [kg / s] H IN : Specific enthalpy of the fluid to be heated flowing into the heating tube 12 [J / kg] H OUT Specific enthalpy [J / kg] of the heated fluid flowing out of the heating tube 12 S ALL :Total surface area of ​​heating tube 12 (=S1+S2+···+S9) [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 The ambient temperature obtained by ST202 is corrected to match (ST206). In other words, the heat flux acquisition device 4 obtains the estimated average heat flux q AVG is the real average heat flux q REAL The corrected ambient temperature is calculated to match the value.

[0109] Furthermore, the heat flux acquisition device 4 calculates the 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 local heat flux over the entire heating tube 12.

[0111] <Alternative Method 1> Next, we will describe Alternative Method 1, which modifies part of the heat flux acquisition process. Regarding Alternative Method 1, unless otherwise specified, the steps ST201-ST207 in the heat flux acquisition process described above are the same.

[0112] In alternative method 1, the heat flux acquisition device 4 can, in step ST202 above, set one of segments G1-G9 (in this case, segment G1) as the representative segment and the other segments (in this case, segments G2-G9) as subordinate segments. Furthermore, the heat flux acquisition device 4 sets the ambient temperature T corresponding to each of the subordinate segments G2-G9. B2 -T B9 And the ambient temperature T corresponding to representative segment G1 B1 Each temperature ratio can be set. Each set temperature ratio is stored in the storage unit 32 as part of the ambient temperature data 53.

[0113] For example, the ambient temperature T corresponding to the dependent segment G2 B2 And the ambient temperature T corresponding to representative segment G1 B1 The temperature ratio α B2 This can be expressed as the ratio of their fourth powers, as shown in equation (6) below. T B2 4 =α B2 ·T B1 4 ...(6)

[0114] Note that the ambient temperature T corresponds to the other dependent segments G3-G9. B3 -T B9 and ambient temperature T B1 The temperature ratio α B3 -α B9 Regarding the temperature ratio α of the dependent segment G2, B2 It can be expressed in the same way as above.

[0115] As a result, the heat flux acquisition device 4 determines the temperature ratio α B2 -α B9 After obtaining this, for example, even if the operating conditions of heating furnace 2 are changed, the ambient temperature T of representative segment G1 will remain unchanged. B1 By obtaining (or calculating) the ambient temperature T, B1 From the dependent segments G2-G9, ambient temperature T B2 -T B9This allows for the calculation of a new value. This reduces the processing load on the heat flux acquisition device 4 for calculating ambient temperature (and consequently, local heat flux).

[0116] To calculate the local heat flux when operating conditions are changed using the ambient temperature ratio described above, the ambient temperature of the dependent segment is calculated from the ambient temperature of the representative segment and the ambient temperature ratio obtained from the operating data. Furthermore, the heat flux at each target point is obtained using the target point temperature and ambient temperature at each target point in all segments.

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

[0118] Next, we will explain how to calculate the temperature value at the target point.

[0119] Local heat flux q at the target point (segment i, subsegment j) i-j This is the outer surface temperature of the heating tube 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 Using [·K / W], it can be expressed as follows in equation (7).

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

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

[0122]

number

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

[0124]

number

[0125] Therefore, from equation (9), T R1-1 (Point P of the heating tube 12) 1-1The outer surface temperature [K] at point P can be calculated. Furthermore, the outer surface temperature at other target points can also be calculated for point P. 1-1 It can be calculated in the same way.

[0126] <Alternative Method 2> Next, we will describe Alternative Method 2, which modifies part of the heat flux acquisition process. Unless otherwise specified, Alternative Method 2 is the same as the heat flux acquisition process described above (see Figure 5).

[0127] In alternative method 2, the past operating conditions of heating furnace 2 and the ambient temperature T of each segment G1-G9 under each operating condition are specified. B1 -T B9 Once the data is prepared, the heat flux acquisition device 4 uses this data as training data to construct a machine learning model. The constructed machine learning model is stored in the memory unit 32 of the heat flux acquisition device 4. While not particularly limited, the machine learning model can use known algorithms such as neural networks.

[0128] The operating conditions for the heating furnace 2 include the combustion conditions within the heating furnace 2 (e.g., fuel composition, fuel pressure, fuel flow rate, etc.). The operating conditions may also include the operating conditions of each burner (fuel supply (injection) pressure, air volume, etc.) and internal furnace conditions (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 uses a machine learning model to determine the ambient temperature T of each segment G1-G9. B1 -T B9 It is possible to estimate the data.

[0130] In addition, under alternative method 2, the machine learning model may be stored on 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 in the heating furnace 2 and local heat flux data for each operating condition may be prepared, and the heat flux acquisition device 4 may construct a machine learning model using this data as training data. Furthermore, the heat flux acquisition device 4 can also utilize a machine learning model constructed by a computer such as another information processing device.

[0131] This concludes the description of specific embodiments. However, the present invention is not limited to the above embodiments or modifications and can be broadly modified and implemented. The components of the heat flux acquisition device, heat flux acquisition system, and heat flux acquisition method for a project shown in the above embodiments are not necessarily all essential, and at least those skilled in the art can appropriately select and omit them as long as they do not deviate from the scope of the present invention. [Explanation of symbols]

[0132] 1: Heat flux acquisition system 2:Heating furnace 3: Field equipment 4: Heat flux acquisition device 5: Communication Network 11: Casing 12:Heating tube 12A: Entrance 12B: Exit 13: Combustion device 14: Upper area 15: Lower area 21: Measuring Instruments 22: Thermography 23: Two color thermometer 24: Terminal device 31: Control Unit 32: Storage section 33: Communications Department 41: Data Acquisition Unit 42:Heat flux calculation section 43:Environmental temperature correction section 44:Heat flux distribution generation part 51: Furnace data 52: Heating tube temperature data 53: Ambient temperature data 54:Heat flux data 55: Heat flux image data A1-A9: Area G1-G9: Segments G 1-1 -G 1-8 : subsegment

Claims

1. A heat flux acquisition device for acquiring the heat flux of an object inside a heating furnace, The system includes a processor that performs processing to obtain the heat flux of the object, The aforementioned processor, The temperature of a target point on the outer surface of the object is obtained by a temperature sensor, The ambient temperature corresponding to the aforementioned target point is obtained, Based on the temperature of the target point and the corresponding ambient temperature, the local heat flux for the target point is calculated. The aforementioned heating furnace is a tubular heating furnace, The object in question is a heat flux acquisition device, including the heating tubes of the tubular heating furnace.

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

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

4. The aforementioned ambient temperature is a corrected ambient temperature determined by calculation. The heating tube has one or more segments and a plurality of target points set for each of the segments. The heat flux acquisition device according to claim 1, wherein the corrected ambient temperature is calculated based on at least the target point temperature measured by the temperature sensor for each of the target points, the amount of heat in the heated fluid flowing into the heating tube, and the amount of heat in the heated fluid flowing out of the heating tube.

5. The aforementioned processor, The temperature of each of the aforementioned target points is obtained, The estimated ambient temperature inside the furnace corresponding to each of the aforementioned segments is obtained, which is estimated based on the temperature of each corresponding target point. Based on the temperatures of each target point and the corresponding estimated ambient temperatures, the estimated local heat flux for each target point is calculated. Based on the estimated local heat flux, the estimated segment average heat flux or estimated segment heat input for each segment is calculated, and based on the estimated segment average heat flux or estimated segment heat input, the estimated average heat flux or estimated heat input for the heating tube is obtained. Based on the amount of heat in the fluid to be heated flowing into the heating tube and the amount of heat in the fluid to be heated flowing out of the heating tube, the actual average heat flux or actual heat input amount for the heating tube is calculated. 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 matches the actual average heat flux, or so that the estimated heat input matches the actual heat input.

6. Each of the aforementioned segments includes a subsegment set to correspond to each of the aforementioned target points, The aforementioned processor, The heat flux acquisition apparatus according to claim 5, wherein the estimated segment average heat flux for each segment is calculated based on a weighted average obtained by using the surface area of ​​each subsegment as the weight of the local heat flux with respect to the corresponding target point.

7. The heating tube has a plurality of segments, including one representative segment and dependent segments other than the representative segment. The estimated ambient temperature of the dependent segment is expressed using the temperature ratio to the estimated ambient temperature of the representative segment. The aforementioned processor, The corrected ambient temperature of the representative segment is calculated so that the estimated average heat flux matches the actual average heat flux, or so that the estimated heat input matches the actual heat input. The heat flux acquisition device according to claim 6, which calculates the corrected ambient temperature of the dependent segment based on the corrected ambient temperature and temperature ratio of the representative segment.

8. The heat flux acquisition device according to claim 7, further comprising a storage device for storing the temperature ratio between the estimated ambient temperature of the dependent segment and the estimated ambient temperature of the representative segment.

9. The aforementioned processor, The temperature of each of the aforementioned target points is obtained, The corrected ambient temperature of the representative segment and the corrected ambient temperature of the dependent segment are obtained. A heat flux acquisition device according to claim 8, which calculates a local heat flux relating to the target point based on the target point temperature, the corrected ambient temperature of the corresponding representative segment, and the corrected ambient temperature of the dependent segment.

10. The heat flux acquisition apparatus according to claim 9, wherein the processor further calculates the target point temperature for the target point based on the corrected ambient temperature of the representative segment and the corrected ambient temperature of the dependent segment.

11. Equipped with additional memory, The aforementioned processor further, Based on the amount of heat in the fluid to be heated flowing into the heating tube and the amount of heat in the fluid to be heated flowing out of the heating tube, the actual average heat flux for the heating tube is calculated. The heat flux acquisition device according to claim 1, which calculates the heat flux ratio between the actual average heat flux and the local heat flux and stores the heat flux ratio in the memory device.

12. The aforementioned processor, The heat flux ratio stored in the memory device is obtained, Based on the amount of heat in the fluid to be heated flowing into the heating tube and the amount of heat in the fluid to be heated flowing out of the heating tube, the actual average heat flux for the heating tube is calculated. The heat flux acquisition device according to claim 11, which acquires the local heat flux based on the heat flux ratio and the actual average heat flux.

13. Equipped with additional storage, The aforementioned processor, The operating conditions of the heating furnace and the ambient temperature under those operating conditions are stored in the storage device. A machine learning model is constructed that takes the operating conditions stored in the memory device as input and outputs the ambient temperature. The heat flux acquisition device according to claim 1.

14. The aforementioned processor, By inputting the new operating conditions of the heating furnace into the machine learning model, the ambient temperature is obtained. Based on the acquired ambient temperature and the temperature at a target point on the outer surface of the object, the local heat flux is calculated. The heat flux acquisition device according to claim 13.

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

16. The aforementioned processor, The heat flux acquisition apparatus according to claim 1, which generates an image visualizing the distribution of the local heat flux.

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

18. The aforementioned processor, The heat flux acquisition device according to claim 17, which acquires the temperature in the temperature distribution of the object as the target point temperature.

19. The heating tube has one or more segments and a plurality of target points set for each segment, The ambient 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 segment based on the target point temperature of each segment and the ambient temperature of each segment.

20. A method for obtaining the heat flux of an object inside a heating furnace, Computers The temperature of a target point on the outer surface of the object is obtained by a temperature sensor, The ambient temperature corresponding to the aforementioned target point is obtained, Based on the temperature of the target point and the corresponding ambient temperature, the local heat flux for the target point is calculated. The aforementioned heating furnace is a tubular heating furnace, The object in question is a method for obtaining heat flux, which includes the heating tubes of the tubular heating furnace.

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