Heat exchanger analysis device and heat exchanger analysis method

Abstract

A heat exchanger analysis device is provided with a time-dependent change acquisition unit, a temperature fluctuation region determination unit, a fluctuation frequency calculation unit, and a fatigue determination unit. The change over time acquisition unit acquires a change over time in the metal temperature measured at a measurement point provided on the heat exchanger. The temperature variation region specifying unit specifies a plurality of temperature variation regions having a temperature variation range on the basis of the change over time. The fluctuation frequency calculation unit calculates the fluctuation frequency of the metal temperature for a predetermined period on the basis of the plurality of temperature fluctuation regions. The fatigue determination unit determines the presence or absence of fatigue in the heat exchange unit at the measurement point on the basis of the fluctuation frequency.

Description

Technical Field

[0001] The invention relates to a heat exchanger analysis device and a heat exchanger analysis method.

[0002] This application is based on the priority of Japanese Patent Application No. 2022-138366 filed with the Japan Patent Office on August 31, 2022, and the contents thereof are incorporated herein by reference. Background Art

[0003] A heat exchanger for performing heat exchange between heat media is known (for example, a coal gasification furnace provided in a coal gasification combined power generation facility is provided with a heat exchanger for performing heat exchange between coal fuel and heat medium to gasify the coal fuel). The performance of such a heat exchanger can be analyzed based on the metal temperature of the portion where the heat exchange is performed. For example, in Patent Document 1, the heat absorption is calculated based on the data obtained by the temperature sensor provided on the heat exchanger, thereby analyzing the performance of the heat exchanger. In this document, in particular, the heat exchanger is divided into a plurality of blocks, and the heat absorption of each block is calculated based on the data detected by the temperature sensor provided on each block, thereby enabling abnormal conditions to be detected at a slight stage even in a relatively large heat exchanger with a complex structure.

[0004] Previous technical literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent No. 6840026 Summary of the invention

[0007] Technical issues to be solved by the invention

[0008] In the above-mentioned Patent Document 1, the metal temperature is measured by a temperature sensor installed on the heat exchanger. When the metal temperature shows a value lower than the representative temperature of the heat medium passing through the heat exchanger, it is determined that there is an abnormality, such as the growth of deposits on the heat transfer pipe of the heat exchanger, which leads to a decrease in thermal conductivity. Here, according to the research of the present inventors, it is found that in such a heat exchanger, when the metal temperature changes over time, a heat load will be generated in the heat exchanger accompanied by temperature changes, thereby causing fatigue. The fatigue caused by this heat load is related to the change of the metal temperature. Therefore, it is difficult to analyze it according to the high or low metal temperature as in Patent Document 1 (for example, in the temperature change including the repeated occurrence of peak temperature changes or the temperature change showing a large peak, that is, a large amplitude peak (big spike), the fatigue caused by the heat load related to the change of the metal temperature has a great influence).

[0009] At least one embodiment of the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a heat exchanger analysis device and a heat exchanger analysis method capable of appropriately analyzing the influence of a heat load caused by a change in metal temperature.

[0010] Means for solving technical problems

[0011] In order to solve the above-mentioned problems, a heat exchanger analysis device according to at least one embodiment of the present invention includes:

[0012] A heat exchanger analysis device, comprising:

[0013] a time-dependent change acquisition unit for acquiring a time-dependent change in the metal temperature measured over a predetermined period at at least one measurement point provided on a heat exchanger for performing heat exchange between heat media;

[0014] a temperature variation region determination unit, configured to determine a plurality of temperature variation regions having temperature variation ranges according to the temporal variation;

[0015] a variation frequency calculation unit configured to calculate the variation frequency of the metal temperature during the predetermined period based on the plurality of temperature variation regions; and

[0016] The fatigue determination unit is configured to determine whether the heat exchange unit at the at least one measurement point is fatigued based on the fluctuation frequency.

[0017] In order to solve the above-mentioned problems, a heat exchanger analysis method according to at least one embodiment of the present invention includes the following steps:

[0018] A heat exchanger analysis method comprising the following steps:

[0019] Acquiring a time-dependent change in a metal temperature measured over a predetermined period at at least one measuring point provided on a heat exchanger for performing heat exchange between heat media;

[0020] determining a plurality of temperature variation regions having temperature variation ranges according to the temporal variation;

[0021] calculating a frequency of variation of the metal temperature during the predetermined period based on the plurality of temperature variation regions; and

[0022] The presence or absence of fatigue of the heat exchange portion at the at least one measurement point is determined based on the frequency of fluctuation.

[0023] Effects of the Invention

[0024] According to at least one embodiment of the present invention, it is possible to provide a heat exchanger analysis device and a heat exchanger analysis method that can appropriately analyze the influence of a heat load due to a change in metal temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of a heat exchanger according to one embodiment.

[0026] Figure 2 It is a diagram showing the structure of a heat exchanger analysis device according to one embodiment.

[0027] Figure 3 It is a flowchart which shows the heat exchanger analysis method which concerns on one Embodiment.

[0028] Figure 4 For Figure 3 An example of the time-dependent change of the metal temperature acquired in step S100.

[0029] Figure 5 To express in Figure 3 A diagram of multiple temperature variation regions determined in step S101.

[0030] Figure 6 1 is a diagram showing an example of classifying a plurality of temperature fluctuation regions into a plurality of groups in step S102 .

[0031] Figure 7 for Figure 6 Statistical example of classification results.

[0032] Figure 8 for Figure 3 An example of display on the display unit in step S106. DETAILED DESCRIPTION

[0033] Hereinafter, several embodiments of the present invention will be described with reference to the drawings. However, the structures described as the embodiments or shown in the drawings are not intended to limit the scope of the present invention to these, but are merely illustrative examples.

[0034] First, a heat exchanger 1 that is an analysis target of a heat exchanger analysis device according to at least one embodiment of the present invention will be described. Figure 1 It is a schematic diagram of a heat exchanger 1 according to one embodiment.

[0035] The heat exchanger 1 is a device for performing heat exchange between heat media. In the present embodiment, as an example of the heat exchanger 1, a SGC (syngas cooler) heat exchanger that generates water vapor for driving a steam turbine by performing heat exchange with a high-temperature generated gas (e.g., coal-containing fuel) generated in a coal gasification combined power plant (IGCC: Integrated Coal Gasification Combined Cycle) is described, but the invention is not limited thereto.

[0036] In the coal gasification combined power generation facility, pulverized coal generated by pulverizing coal fuel is burned together with air in a coal gasification furnace (not shown), thereby generating high-temperature generated gas through a gasification reaction. The generated gas is transported to a heat exchanger 1 as a heat medium, and heat is exchanged with cooling water, which is another hot and cold medium, through a heat transfer wall 2 made of a metal material having thermal conductivity. The cooling water becomes steam by receiving heat from the generated gas, and is transported to a steam turbine (not shown).

[0037] At least one measuring point 4 for measuring the temperature of the heat-conducting wall 2 (hereinafter appropriately referred to as "metal temperature T") is provided on the heat-conducting wall 2 of the heat exchanger 1. A temperature sensor such as a thermocouple is provided at the measuring point 4, for example. In the present embodiment, a plurality of measuring points 4 are provided at different positions of the heat-conducting wall 2. At each of the plurality of measuring points 4, the metal temperature T is detected by a temperature sensor, and these metal temperatures T are used for calculations performed by the heat exchanger analysis device described later.

[0038] Next, a heat exchanger analysis device 100 for analyzing the heat exchanger 1 having the above-described structure will be described. Figure 2 1 is a diagram showing the structure of a heat exchanger analysis device 100 according to an embodiment.

[0039] The heat exchanger analysis device 100 is composed of, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and a computer-readable storage medium. Moreover, as for a series of processes for realizing various functions, as an example, they are stored in a storage medium in the form of a program, and the CPU reads the program into the RAM and executes information processing / calculation processing to realize various functions. In addition, the program can also be applied in a manner of being pre-installed in a ROM or other storage medium, provided in a state stored in a computer-readable storage medium, or transmitted via a wired or wireless communication mechanism. Computer-readable storage media are magnetic disks, optical magnetic disks, CD-ROMs, DVD-ROMs, semiconductor memories, and the like.

[0040] The heat exchanger analysis device 100 that realizes various functions by executing programs in this manner includes a temporal change acquisition unit 102 , a temperature fluctuation region identification unit 104 , a fluctuation frequency calculation unit 106 , a fatigue determination unit 108 , and a display unit 110 as functional components.

[0041] In the following description, the configuration of the heat exchanger analysis device 100 is described as an example in which the heat exchanger 1 at one measurement point 4 is analyzed based on the metal temperature T detected by the temperature sensor installed at the measurement point 4. Figure 1 As shown, when a plurality of measuring points 4 are provided on the heat exchanger 1 , unless otherwise described, the configuration of the heat exchanger analysis device 100 performs the analysis of the heat exchanger 1 at each measuring point 4 by performing the same processing on each measuring point 4 .

[0042] The temporal variation acquisition unit 102 is configured to acquire temporal variation of the metal temperature T measured over a predetermined period at the measurement point 4. The temporal variation acquisition unit 102 acquires temporal variation of the metal temperature T over a predetermined period by continuously acquiring detection values ​​of the temperature sensor provided at the measurement point 4.

[0043] For details on the change of the metal temperature T over time, please refer to Figure 4 This will be described later.

[0044] The temperature variation region determination unit 104 is configured to determine the temperature variation region based on the temporal variation of the metal temperature T. Generally, the metal temperature T changes moment by moment with the passage of time. The temperature variation region determination unit 104 determines a range having a predetermined temperature variation range as the temperature variation region based on the temporal variation of the metal temperature T.

[0045] Furthermore, the time-dependent change of the metal temperature T includes various forms with various temperature fluctuation ranges, and therefore, the temperature fluctuation region determination unit 104 can determine the range of temperature fluctuation ranges with a certain reference value or more as the temperature fluctuation region. Thus, as follows: regarding a small temperature change with a temperature fluctuation range smaller than the reference value, since the influence on the fatigue analysis of the heat exchanger 1 is small, it can be ignored, and the fatigue judgment of the heat exchanger can be appropriately performed based on the temperature change that has a large influence on the fatigue analysis of the heat exchanger 1.

[0046] In addition, for details on the determination of the temperature change region by the temperature change region determination unit 104, please refer to Figure 5 This will be described later.

[0047] The variation frequency calculation unit 106 is configured to calculate the variation frequency of the metal temperature T in a predetermined period based on the plurality of temperature variation regions determined by the temperature variation region determination unit 104. The variation frequency is calculated based on, for example, how many temperature variation regions determined by the temperature variation region determination unit 104 are included in the predetermined period corresponding to the temporal variation of the metal temperature T acquired by the temporal variation acquisition unit 102.

[0048] For details on the calculation of the change frequency by the change frequency calculation unit 106, please refer to Figure 6 and Figure 7 This will be described later.

[0049] The fatigue determination unit 108 is configured to determine whether fatigue exists at the measuring point 4 based on the fluctuation frequency calculated by the fluctuation frequency calculation unit 106. The fluctuation frequency refers to the frequency of fluctuation of the metal temperature T within a predetermined period, and is related to fatigue caused by the heat load to the heat exchanger. The fatigue determination unit 108 analyzes the fatigue degree corresponding to the fluctuation frequency calculated by the fluctuation frequency calculation unit 106 based on this correlation, thereby determining whether fatigue exists.

[0050] The display unit 110 is configured to display various information processed by the heat exchanger analysis device 100. The various information displayed by the display unit 110 may include, for example, the determination result of the fatigue determination unit 108. In this case, Figure 1 As shown, when multiple measuring points 4 are set, the analysis results of each measuring point 4 can be displayed, and the comprehensive analysis results of the heat exchanger 1 as a whole obtained based on the analysis results of multiple measuring points 4 can also be displayed. Figure 8 As described later, fatigue distribution obtained based on the analysis results at each measurement point 4 of the heat exchanger 1 is displayed.

[0051] Next, a heat exchanger analysis method performed by the heat exchanger analysis device 100 having the above-described structure will be described. Figure 3It is a flowchart which shows the heat exchanger analysis method which concerns on one Embodiment.

[0052] First, the time-varying acquisition unit 102 acquires the time-varying VT of the metal temperature T measured over a predetermined period t at at least one measuring point 4 provided on the heat exchanger 1 (step S100). In step S100, the time-varying acquisition unit 102 acquires the metal temperature T detected by the temperature sensor provided at the measuring point 4 in real time over the predetermined period t. In step S100, the time-varying VT of the metal temperature T may be acquired by storing the metal temperature T and time obtained by the temperature sensor over a predetermined period in the past in a storage device (not shown) together with the time, and reading the metal temperature T over a predetermined period from the storage device.

[0053] Figure 4 For Figure 3 An example of the time variation VT of the metal temperature T acquired in step S100 of FIG. In this example, the time variation of the metal temperature T detected by the temperature sensor installed at a certain measurement point 4 is displayed over a predetermined period t set in advance. The metal temperature T changes moment by moment, repeatedly rising or falling, and thus has a predetermined waveform with respect to the time axis.

[0054] Next, the temperature change region determination unit 104 determines a plurality of temperature change regions R based on the time-varying VT acquired in step S100 (step S101). The temperature change region R is determined as a range in which the temperature changes with a predetermined temperature change width in the time-varying VT of the metal temperature T. As described above, the temperature change region determination unit 104 may determine as the temperature change region R a range in which the temperature changes with a temperature change width greater than a preset reference value.

[0055] Here, Figure 5 To express in Figure 3 A diagram of the plurality of temperature variation regions R1, R2, ... determined in step S101. Figure 5 In the example, the plurality of temperature change regions R1, R2, ... determined by the temperature change region determination unit 104 are displayed in a distinguishable manner using different hatchings. Figure 4 The temporal variation VT of the metal temperature T shown is applied with rain flow analysis to determine a plurality of temperature variation regions R1, R2, ... In this way, in step S101, by applying rain flow analysis, a plurality of temperature variation regions R1, R2, ... are appropriately determined according to the temporal variation VT of the metal temperature T.

[0056] In addition, Figure 5FIG. 2 exemplifies a case where the temperature variation region R is determined by applying the rain flow analysis. The rain flow analysis is one of the methods for fatigue life analysis under irregular repeated fluctuations, and other methods such as the range pair count method may be applied instead of this method.

[0057] Next, the variation frequency calculation unit 106 calculates the variation frequency VR of the metal temperature T in the predetermined period t based on the plurality of temperature variation regions R1, R2, ... determined in step S101 (step S102). The variation frequency VR in step S102 can be calculated, for example, as follows: the plurality of temperature variation regions R1, R2, ... are classified into a plurality of groups G1, G2, ... set according to the size of the temperature variation width TW, and the variation frequency VR is calculated based on the sum of the variation frequencies vr of the temperature variation regions R under each of the plurality of groups G1, G2, ... Figure 6 2 is a diagram showing an example of classifying a plurality of temperature change regions R1, R2, ... into a plurality of groups G1, G2, ... in step S102. Figure 7 for Figure 6 Statistical example of classification results.

[0058] exist Figure 6 In the embodiment, a plurality of groups G1, G2, ... are defined according to the size of the temperature variation range TW. Group G1 is a group into which the temperature variation range R of which the temperature variation range TW is TW1≤TW<TW2 is classified, group G2 is a group into which the temperature variation range R of which the temperature variation range TW is TW2≤TW<TW3 is classified, group G3 is a group into which the temperature variation range R of which the temperature variation range TW is TW3≤TW<TW4 is classified, and group G4 is a group into which the temperature variation range R of which the temperature variation range TW is TW4≤TW<TW5 is classified (in addition, TW1<TW2<TW3<TW4<TW5, for example, TW1=0(℃), TW2=12(℃), TW3=24(℃), TW4=36(℃), TW5=48(℃)).

[0059] In addition, Figure 6 The example in which the plurality of temperature variation regions R1, R2, ... are classified into four groups is shown, but the number of groups is not limited thereto. For example, by increasing the number of groups, the accuracy of heat load calculation can be improved.

[0060] Among the multiple temperature change regions R1, R2, ... determined in step S101, the temperature change regions R1, R4, R5, R6, R8, and R9 having similar temperature change amplitudes TW are classified into group G1. The temperature change region R2 having the second largest temperature change amplitude TW is classified into group G2. The temperature change region R3 having the second largest temperature change amplitude TW is classified into group G3. The temperature change region R7 having the second largest temperature change amplitude TW is classified into group G4. In this case, the change frequency calculation unit 106 calculates the change frequency vr1 (=240) corresponding to group G1 by converting the number of classifications of group G1, i.e., the number of changes "6" for a specified time t (=1.5 minutes) into a unit time (=1 hour). Similarly, the change frequency calculation unit 106 calculates the change frequency vr2 (=40) corresponding to group G2 by converting the number of classifications of group G2, i.e., the number of changes "1" for a specified time t (=1.5 minutes) into a unit time (=1 hour). Similarly, the change frequency calculation unit 106 calculates the change frequency vr3 (=40) corresponding to the group G3 by converting the number of classifications, i.e., the number of changes "1", of the group G3 at the predetermined time t (=1.5 minutes) into the unit time (=1 hour). Similarly, the change frequency calculation unit 106 calculates the change frequency vr4 (=40) corresponding to the group G4 by converting the number of classifications, i.e., the number of changes "1" of the group G4 at the predetermined time t (=1.5 minutes) into the unit time (=1 hour). Then, the change frequency calculation unit 106 calculates the change frequency VR (=360) at the predetermined time t as the sum of the change frequencies vr1, vr2, ... of the groups G1, G2, ...

[0061] Furthermore, in step S102, the variation frequency calculation unit 106 may use a weighting coefficient set according to the temperature variation range TW corresponding to each group when calculating the variation frequency VR as the sum of the variation frequencies vr of each group. Thus, the influence of the temperature variation range TW on fatigue is reflected in the variation frequency VR based on the weighting coefficient, so that fatigue analysis can be performed better.

[0062] In this case, the weighting coefficient can be set to increase as the temperature variation range TW corresponding to each group increases. In the present embodiment, the temperature variation range TW increases in the order of groups G1, G2, ..., and therefore, the weighting coefficients corresponding to the variation frequencies vr1, vr2, ... are set to increase in sequence. According to the research of the present inventors, it is found that as the temperature variation range TW increases, the fatigue of the heat exchanger 1 brought by the temperature variation region R tends to increase. Therefore, by setting the weighting coefficient used in calculating the variation frequency VR to increase as the temperature variation range TW increases, fatigue analysis can be performed that appropriately incorporates the influence of the temperature variation range TW on fatigue.

[0063] Next, return Figure 3 , the fatigue determination unit 108 determines whether fatigue exists at the measurement point 4 based on the change frequency VR calculated in step S103 (step S103). In step S103, the presence or absence of fatigue is determined based on whether the change frequency VR calculated as described above is greater than a preset threshold VR0. Specifically, when the change frequency VR is greater than the threshold VR0 (step S103: "Yes"), it is determined that fatigue exists (step S104). In addition, when the change frequency VR is less than the threshold VR0 (step S103: "No"), it is determined that there is no fatigue (step S105).

[0064] In addition, in step S103, the fatigue determination unit 108 accumulates the change frequency VR calculated in step S102 for a predetermined period t, and when the accumulated result is greater than a preset threshold VR0, fatigue can be determined. Thus, when a heat load exceeding a predetermined amount is accumulated in the heat exchanger 1 over time, fatigue is determined, thereby enabling fatigue monitoring of the heat exchanger to be performed.

[0065] Next, the display unit 110 displays the analysis result of the fatigue determination unit 108 (step S106). The display of the analysis result in step S106 is performed in a manner that the operator can recognize, such as on a display. As one example of displaying the analysis result, Figure 1 As shown, when the metal temperature T is measured at a plurality of measurement points 4, the presence or absence of fatigue at each measurement point 4 is displayed in a distinguishable manner.

[0066] Here, Figure 8 for Figure 3 This is an example of a display on the display unit 110 in step S106. Figure 8 In FIG. 1 , a plurality of measuring points 4 are schematically shown together with Figure 1 The heat exchanger 1 shown in FIG. 1 is shown. The metal temperature T detected at each measuring point 4 is used for fatigue determination at each measuring point 4 through the above-mentioned calculation processing. In this display example, based on the fatigue determination results at each measuring point 4, the measuring point 4 determined to be fatigued is highlighted and displayed compared to the measuring point 4 determined to be non-fatigued, thereby distinguishing them. Therefore, the operator who refers to this display can easily understand which of the multiple measuring points 4 set on the heat exchanger 1 is fatigued.

[0067] As described above, according to the above-mentioned embodiments, the temperature variation region R where the temperature variation occurs is determined based on the temporal variation of the metal temperature T at the measuring point 4 provided on the heat exchanger 1, thereby calculating the variation frequency VR of the metal temperature T in the predetermined period t. The variation of the metal temperature T is the main cause of the heat load on the heat exchanger 1, and therefore, it is possible to appropriately analyze whether the heat exchanger 1 is fatigued due to the heat load based on the variation frequency VR of the metal temperature T calculated in this way.

[0068] Furthermore, the components in the above-described embodiments may be appropriately replaced with well-known components without departing from the spirit of the present invention, and the above-described embodiments may be appropriately combined.

[0069] The contents described in the above-mentioned embodiments can be understood, for example, as follows.

[0070] (1) A heat exchanger analysis device according to one embodiment comprises:

[0071] A heat exchanger analysis device, comprising:

[0072] a time-dependent change acquisition unit for acquiring a time-dependent change in the metal temperature measured over a predetermined period at at least one measurement point provided on a heat exchanger for performing heat exchange between heat media;

[0073] a temperature variation region determination unit, configured to determine a plurality of temperature variation regions having temperature variation ranges according to the temporal variation;

[0074] a variation frequency calculation unit configured to calculate the variation frequency of the metal temperature during the predetermined period based on the plurality of temperature variation regions; and

[0075] The fatigue determination unit is configured to determine whether the heat exchange unit at the at least one measurement point is fatigued based on the fluctuation frequency.

[0076] According to the method described in (1) above, the temperature variation region where the temperature variation occurs is determined based on the time-dependent variation of the metal temperature at the measuring point provided on the heat exchanger, thereby calculating the variation frequency of the metal temperature in a predetermined period. The variation of the metal temperature is the main cause of the heat load on the heat exchanger, and therefore, it is possible to appropriately analyze whether the heat exchanger is fatigued due to the heat load based on the variation frequency of the metal temperature calculated in this way.

[0077] (2) In another embodiment, in the embodiment described in (1) above,

[0078] The variation frequency calculation unit classifies the plurality of temperature variation regions into a plurality of groups set according to the magnitude of the temperature variation width, and calculates the variation frequency based on the sum of the numbers of the temperature variation regions belonging to each of the plurality of groups.

[0079] According to the method described in (2) above, the plurality of temperature variation regions included in the time-dependent variation of the metal temperature are classified into a plurality of groups set according to the magnitude of the temperature variation range. The number of the temperature variation regions classified into each group is counted for each group and the sum is calculated, thereby appropriately calculating the variation frequency for determining the presence or absence of fatigue.

[0080] (3) In another embodiment, in the embodiment described in (2),

[0081] The variation frequency calculation unit calculates the total by multiplying the number of the temperature variation regions belonging to the plurality of groups by a weighting coefficient set according to the magnitude of the temperature variation range.

[0082] According to the method described in (3) above, when obtaining the sum for calculating the variation frequency, the number of each temperature variation region is multiplied by a weighting coefficient set according to the magnitude of the temperature variation amplitude. Thus, the influence of the magnitude of the temperature variation amplitude on fatigue is reflected in the variation frequency based on the weighting coefficient, so that fatigue analysis can be performed better.

[0083] (4) In another embodiment, in the embodiment described in (3),

[0084] The weighting coefficient is set to increase as the temperature variation range corresponding to the group increases.

[0085] According to the research conducted by the present inventors, it has been found that as the temperature fluctuation range increases, the fatigue of the heat exchanger caused by the temperature fluctuation region tends to increase. According to the method described in (4) above, by setting the weighting coefficient used in calculating the fluctuation frequency to increase as the temperature fluctuation range increases, fatigue analysis can be performed that appropriately incorporates the effect of the temperature fluctuation range on fatigue.

[0086] (5) In another embodiment, in any one of the embodiments (1) to (4),

[0087] The fatigue determination unit accumulates the frequency of change in the predetermined period, and determines that the fatigue is present when the accumulated result exceeds a preset threshold value.

[0088] According to the method described in (5) above, the frequency of change calculated based on the temperature change region determined based on the time-dependent change of the metal temperature is accumulated for a predetermined period. If the accumulated result exceeds a threshold value, it is determined that the heat exchanger is fatigued. In this way, the fatigue accumulated in the heat exchanger over time can be appropriately analyzed.

[0089] (6) In another embodiment, in any one of the embodiments (1) to (5),

[0090] The temperature change region determination unit determines the plurality of temperature change regions by performing a rainflow analysis on the temporal change.

[0091] According to the aspect described in (6) above, by using the rain flow analysis, a plurality of temperature variation regions can be appropriately determined based on the temporal variation of the metal temperature. In addition, other methods such as the pair counting method may be used instead of the rain flow analysis.

[0092] (7) In another embodiment, in any one of the embodiments (1) to (6),

[0093] The at least one measuring point includes a plurality of measuring points provided at different positions of the heat exchanger.

[0094] According to the method described in (7) above, the time-dependent change of the metal temperature is obtained at a plurality of measuring points arranged at different positions of the heat exchanger. The time-dependent change of the metal temperature obtained at each measuring point is processed as described above to perform fatigue analysis at each measuring point. Thus, the fatigue distribution state at a plurality of positions of the heat exchanger can be appropriately analyzed.

[0095] (8) In another embodiment, in the embodiment described in (7),

[0096] A display unit is further provided for displaying the analysis result of the fatigue determination unit for the plurality of measurement points in a manner that allows the presence or absence of the fatigue to be distinguished.

[0097] According to the aspect described in (8) above, by displaying the analysis results obtained at a plurality of measurement points in a manner that allows the presence or absence of fatigue to be distinguished, the fatigue state of the heat exchanger can be appropriately grasped.

[0098] (9) In another embodiment, in any one of the embodiments (1) to (8),

[0099] The heat exchanger is configured to replace coal fuel with the heat medium in a coal gasification furnace provided in a coal gasification combined power plant.

[0100] According to the aspect described in (9) above, the fatigue state of the coal gasification furnace included in the coal gasification combined power plant can be appropriately analyzed.

[0101] (10) A heat exchanger analysis method according to one embodiment comprises the following steps:

[0102] A heat exchanger analysis method comprising the following steps:

[0103] Acquiring a time-dependent change in a metal temperature measured over a predetermined period at at least one measuring point provided on a heat exchanger for performing heat exchange between heat media;

[0104] determining a plurality of temperature variation regions having temperature variation ranges according to the temporal variation;

[0105] calculating a frequency of variation of the metal temperature during the predetermined period based on the plurality of temperature variation regions; and

[0106] The presence or absence of fatigue of the heat exchange portion at the at least one measurement point is determined based on the frequency of fluctuation.

[0107] According to the method described in (10) above, the temperature variation region where the temperature variation occurs is determined based on the time-dependent variation of the metal temperature at the measuring point provided on the heat exchanger, thereby calculating the variation frequency of the metal temperature in a predetermined period. The variation of the metal temperature is the main cause of the heat load on the heat exchanger, and therefore, it is possible to appropriately analyze whether the heat exchanger is fatigued due to the heat load based on the variation frequency of the metal temperature calculated in this way.

[0108] Explanation of symbols

[0109] 1- heat exchanger, 2- thermal pad, 4- measuring point, 100- heat exchanger analysis device, 102- time change acquisition unit, 104- temperature change region determination unit, 106- change frequency calculation unit, 108- fatigue determination unit, 110- display unit.

Claims

1. A heat exchanger analysis device, comprising: a time-dependent change acquisition unit for acquiring a time-dependent change in the metal temperature measured over a predetermined period at at least one measurement point provided on a heat exchanger for performing heat exchange between heat media; a temperature variation region determination unit, configured to determine a plurality of temperature variation regions having temperature variation ranges according to the temporal variation; a variation frequency calculation unit for calculating the variation frequency of the metal temperature during the specified period based on the plurality of temperature variation regions; and The fatigue determination unit is configured to determine whether the heat exchange unit at the at least one measurement point is fatigued based on the fluctuation frequency.

2. The heat exchanger analysis device according to claim 1, wherein: The variation frequency calculation unit classifies the plurality of temperature variation regions into a plurality of groups set according to the magnitude of the temperature variation width, and calculates the variation frequency based on the sum of the numbers of the temperature variation regions belonging to each of the plurality of groups.

3. The heat exchanger analysis device according to claim 2, wherein: The variation frequency calculation unit calculates the total by multiplying the number of the temperature variation regions belonging to the plurality of groups by a weighting coefficient set according to the magnitude of the temperature variation range.

4. The heat exchanger analysis device according to claim 3, wherein: The weighting coefficient is set to increase as the temperature variation range corresponding to the group increases.

5. The heat exchanger analysis device according to claim 1 or 2, wherein: The fatigue determination unit accumulates the frequency of change in the predetermined period, and determines that the fatigue is present when the accumulated result exceeds a preset threshold value.

6. The heat exchanger analysis device according to claim 1 or 2, wherein: The temperature change region determination unit determines the plurality of temperature change regions by performing a rainflow analysis on the temporal change.

7. The heat exchanger analysis device according to claim 1 or 2, wherein: The at least one measuring point includes a plurality of measuring points provided at different positions of the heat exchanger.

8. The heat exchanger analysis device according to claim 7, further comprising: The display unit is configured to display the analysis results of the fatigue determination unit for the plurality of measurement points in a manner that allows the presence or absence of the fatigue to be distinguished.

9. The heat exchanger analysis device according to claim 1 or 2, wherein: The heat exchanger is configured to replace coal fuel with the heat medium in a coal gasification furnace provided in a coal gasification combined power plant.

10. A heat exchanger analysis method comprising the following steps: Acquiring a time-dependent change in a metal temperature measured over a predetermined period at at least one measuring point provided on a heat exchanger for performing heat exchange between heat media; determining a plurality of temperature variation regions having temperature variation ranges according to the temporal variation; calculating a frequency of variation of the metal temperature during the predetermined period based on the plurality of temperature variation regions; and The presence or absence of fatigue of the heat exchange portion at the at least one measurement point is determined based on the frequency of fluctuation.

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