An online analysis method for the heat pipe heat transfer state and an electronic device

Abstract

The present invention discloses an online analysis method and an electronic device for the heat pipe heat exchange state, which respectively detect the states of the media on the flue gas side and the water side, and calculate Q 烟 and Q 水 , to obtain the actual heat transfer efficiency η 实 at the current moment. By comparing the actual heat transfer efficiency η 实 with the set heat exchange efficiency, it can be known whether the heat exchange state of the heat pipe has decreased. Using two calculation forms of the actual heat transfer efficiency, by setting the values of the ash fouling influence factor k1 and the heat exchange influence factor k2, the ash fouling degree evaluation value X1 and the heat exchange attenuation evaluation value X2 at the current moment can be calculated. Then, by substituting each data into the observation state equation, the heat transfer efficiency η` at the next moment can be calculated, and then the optimal estimated values of X1 and X2 can be deduced inversely. By using the Kalman filter to filter the state variables, the optimal estimated values of the ash fouling degree evaluation value and the heat exchange attenuation evaluation value can be obtained, realizing the online analysis of the heat exchange state of the heat pipe.

Description

Technical Field

[0001] The present invention relates to the technical field of heat exchange detection, and particularly to an online analysis method for the heat exchange state of heat pipes and an electronic device. Background Art

[0002] In various coal-fired units and metallurgical and chemical equipment, a large amount of flue gas with high temperature and high enthalpy value at the tail is generally generated. When recovering and utilizing waste heat, a heat exchanger with a high negative pressure axial heat transfer conductor, also known as a heat pipe, is often used for heat exchange.

[0003] A heat pipe is a high-vacuum heat transfer pipe that operates independently. It is divided into a heat absorption side and a heat release side. The heat absorption side is inserted into the flue gas side, and the heat release side is inserted into the cooling water tank. The cooling water tank is isolated from the flue gas side. By using the phase change heat transfer of the heat transfer medium inside the heat pipe, the heat of the flue gas side is transferred to the cooling water tank, and the bottom of the cooling water tank serves as the partition between the flue gas side and the water side.

[0004] However, due to the very complex composition of the tail flue gas, it often contains dust and corrosive gases. The dust will adhere to the surface of the heat pipe on the flue gas side, affecting the heat exchange efficiency. The corrosive gas will corrode the heat pipe and the bottom of the water tank, causing leakage. And often in the initial stage of leakage, due to the large number of heat pipes, when a small amount of heat leaks with a small flow rate, the impact on the overall heat exchange effect is small, and it is not easy for the staff to detect. By the time the staff notices that the heat exchange effect has deteriorated, large-area corrosion and leakage may have occurred, resulting in high maintenance costs and the inability to analyze the heat exchange state of the heat pipe online in real time. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. For this purpose, the object of the present invention is to provide an online analysis method for the heat exchange state of heat pipes and an electronic device to solve the problems such as the inability to analyze the heat exchange state of heat pipes online when recovering waste heat using heat pipes in the prior art.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect, an embodiment of the present application provides an online analysis method for the heat exchange state of heat pipes, including:

[0008] According to the heat absorption Q 烟 of the heat pipe on the flue gas side and the heat exchange Q 水 of the heat pipe on the water side, calculate the actual heat transfer efficiency η 实 = Q 水 / Q 烟 ;

[0009] When the actual heat transfer efficiency η 实 is less than the set heat exchange efficiency η 设 , perform the following analysis:

[0010] Set the dust accumulation influence factor k1 and the heat transfer influence factor k2, and use a linear function for fitting to obtain the actual heat transfer efficiency η 实 = k1*X1 + k2*X2, where X1 is the evaluation value of the dust accumulation degree and X2 is the evaluation value of the heat transfer attenuation;

[0011] Establish the observation state equation η` = A*X + e, where A is the observation matrix, X is the state variable, X = [X1 X2] T , and e is the error matrix;

[0012] Filter the state variable X through Kalman filtering to obtain the optimal estimated values of X1 and X2.

[0013] In some embodiments, set the pressure difference ΔP of the flue gas before and after passing through the heat pipe, and the flue gas resistance influence factor k3. According to linear function fitting, the evaluation value of the dust accumulation degree X1 = k3*ΔP, and the observation matrix A = [k1*k3 k2].

[0014] In some embodiments, on the flue gas side, detect the inlet temperature t of the flue gas inlet state 烟进 、inlet flow rate G 烟进 , detect the outlet temperature t of the flue gas outlet state 烟出 、outlet flow rate G 烟出 ;

[0015] According to Q 烟 = C 烟 *G 烟进 *t 烟进 -C 烟 *G 烟出 *t 烟出 , calculate the heat Q absorbed by the heat pipe on the flue gas side 烟 .

[0016] In some embodiments, on the water side, detect the inlet temperature t of the circulating water inlet state 水进 、inlet flow rate G 水进 , detect the outlet temperature t of the circulating water outlet state 水出 、outlet flow rate G 水出 ;

[0017] According to Q 水 = C 水 *G 水出 *t 水出 -C 水 *G 水进 *t 水进 , calculate the heat Q released by the heat pipe on the water side 水 .

[0018] In some embodiments, on the flue gas side, detect the pressure P of the flue gas inlet state烟进 , detect the pressure P of the flue gas outlet state 烟出 , calculate to obtain ΔP = P 烟进 - P 烟出 ;

[0019] Combine the inlet temperature t 烟进 , the inlet flow rate G 烟进 , the outlet temperature t 烟出 , the outlet flow rate G 烟出 , calculate the reduced resistance ΔP of the heat pipe on the flue gas side 折 , compare it with the theoretical resistance of the heat pipe on the flue gas side to obtain the fouling influence factor k1.

[0020] In some embodiments, determine whether G 水出 is less than G 水进 ;

[0021] If so, it proves that the water tank where the heat pipe is located leaks, then calculate the leakage amount G according to the water flow difference between the inlet and outlet of the water side 水泄 = G 水进 - G 水出 ;

[0022] Calculate the heat absorption Q of the leaked water on the flue gas side 水泄 ;

[0023] Then Q 烟 = Q 水 + Q 水泄 , the actual heat transfer efficiency η of the heat pipe 实 = (Q 水+ Q 水泄 ) / Q 烟 .

[0024] In some embodiments, determine whether G 烟出 is greater than G 烟进 ;

[0025] If so, it proves that the water tank where the heat pipe is located leaks, then calculate the leakage amount G according to the flue gas flow difference between the inlet and outlet of the flue gas side 烟泄 = G 烟出 - G 烟进 ;

[0026] Calculate the heat absorption Q of the leaked water on the flue gas side 烟泄 ;

[0027] Then Q 烟 = Q 水 + Q 烟泄 , the actual heat transfer efficiency η of the heat pipe 实 = (Q 水+ Q 烟泄 ) / Q 烟 .

[0028] In some embodiments, when G is satisfied simultaneously 水出 less than G 水进 and G 烟出 greater than G 烟进 ;

[0029] Calculate Q 均泄 =(Q 水泄 +Q 烟泄 ) / 2;

[0030] Then Q 烟 =Q 水 +Q 均泄 , and the actual heat transfer efficiency η of the heat pipe 实 =(Q 水+ Q 均泄 ) / Q 烟 .

[0031] In some embodiments, the temperature at the end of the condensation section of each heat pipe is detected, a temperature change curve is plotted for each heat pipe, and the wall temperature of each heat pipe is detected;

[0032] Combined with t 烟进 , t 烟出 , t 水进 , t 水出 , Q 水 , Q 烟 , analyze the heat transfer attenuation state of each heat pipe.

[0033] In a second aspect, an embodiment of the present application provides an electronic device, including a processor and a memory. At least one instruction, at least one program, a code set, or an instruction set is stored in the memory, and the at least one instruction, at least one program, the code set, or the instruction set is loaded and executed by the processor to implement the online analysis method as described above.

[0034] Compared with the prior art, the present invention at least includes the following beneficial effects:

[0035] The online analysis method and electronic device for the heat transfer state of the heat pipe provided by the embodiment of the present application respectively detect the states of the media on the flue gas side and the water side, calculate Q 烟 and Q 水 , obtain the actual heat transfer efficiency η at the current moment 实， The actual heat transfer efficiency η 实By comparing with the set heat exchange efficiency, it can be known whether the heat exchange state of the heat pipe has decreased. Using two calculation forms of the actual heat transfer efficiency, by setting the values of the fouling influence factor k1 and the heat exchange influence factor k2, the fouling degree evaluation value X1 and the heat exchange attenuation evaluation value X2 at the current moment can be calculated. Then, substituting each data into the observation state equation, the heat transfer efficiency η` at the next moment can be calculated, and then the optimal estimated values of X1 and X2 can be deduced. Using the Kalman filter to filter the state variables, the optimal estimated values of the fouling degree evaluation value and the heat exchange attenuation evaluation value can be obtained, realizing the online analysis of the heat exchange state of the heat pipe.

[0036] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present invention will be further described with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation to the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the following drawings.

[0038] Figure 1 It is a schematic structural diagram of the waste heat recovery system applied to the online analysis method of the heat exchange state of a heat pipe provided by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0040] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0041] In the description of the present invention, when it is described that a specific device is located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device. When it is described that a specific device is connected to other devices, the specific device may be directly connected to the other devices without an intermediate device, or may not be directly connected to the other devices but have an intermediate device.

[0042] Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such technologies, methods, and devices shall be regarded as part of the specification.

[0043] In a first aspect, referring to Figure 1 , this embodiment provides an online analysis method for the heat transfer state of heat pipes. This online analysis method is applied to a waste heat recovery system with multiple heat pipes. More specifically, the evaporation section of each heat pipe extends into the flue gas duct, where high-temperature and high-enthalpy flue gas flows. The flue gas passes through the evaporation sections of multiple heat pipes, and its temperature drops. The heat pipes absorb heat on the flue gas side; the condensation section of each heat pipe extends into the cooling water tank, where a cooling medium, generally water, flows. The cooling water passes through the condensation sections of multiple heat pipes, and its temperature rises. The heat pipes release heat on the water side. Between the flue gas side and the water side, they are separated by an adiabatic partition, which is generally arranged at the bottom of the water tank; under a certain heat transfer state, each heat pipe has its corresponding relatively stable heat transfer efficiency.

[0044] In this embodiment, the online analysis method for the heat transfer state of heat pipes includes:

[0045] According to the heat absorption Q 烟 on the flue gas side of the heat pipe and the heat transfer amount Q 水 on the water side of the heat pipe, calculate the actual heat transfer efficiency η 实 = Q 水 / Q 烟 ; The heat absorption Q 烟 on the flue gas side of the heat pipe and the heat transfer amount Q 水 on the water side of the heat pipe are both calculated from the media outside the heat pipe;

[0046] Among them, on the flue gas side, a temperature sensor and a flow sensor are respectively arranged at the inlet end and the outlet end of the flue gas to detect the inlet temperature t 烟进 and the inlet flow rate G 烟进 of the flue gas inlet state, and detect the outlet temperature t 烟出 and the outlet flow rate G 烟出 of the flue gas outlet state;

[0047] According to Q 烟 = C 烟 * G 烟进 * t 烟进 - C 烟 * G 烟出 * t 烟出 , calculate the heat Q 烟 absorbed by the heat pipe on the flue gas side, C 烟is the specific heat of the flue gas on the flue gas side. According to the states of the flue gas at both ends of the inlet and outlet of the flue, the heat released by the flue gas can be calculated, which is also the heat absorption of the heat pipe on the flue gas side, Q 烟 .

[0048] On the water side, a temperature sensor and a flow sensor are respectively set at the inlet end and the outlet end of the circulating water to detect the inlet temperature t 水进 and the inlet flow rate G 水进 of the circulating water inlet state, and to detect the outlet temperature t 水出 and the outlet flow rate G 水出 of the circulating water outlet state;

[0049] According to Q 水 =C 水 *G 水出 *t 水出 -C 水 *G 水进 *t 水进 , calculate the heat released by the heat pipe on the water side, Q 水 , C 水 is the specific heat of the cooling water on the water side. According to the states of the cooling water at both ends of the inlet and outlet of the water tank, the heat absorbed by the cooling water can be calculated, which is also the heat exchange amount of the heat pipe on the water side, Q 水 .

[0050] Since the specific heat absorption and heat release of the heat transfer medium inside the heat pipe cannot be measured, in order to evaluate its heat exchange efficiency, it is necessary to measure from the flue gas side and the water side outside the heat pipe and transfer to the side that is easier to measure and calculate.

[0051] When the actual heat transfer efficiency η 实 is less than the set heat exchange efficiency η 设 , it indicates that the heat pipe surface is fouled or the heat pipe fails or the heat exchange efficiency decreases, etc. Then the following analysis is carried out:

[0052] Set the fouling influence factor k1 and the heat exchange influence factor k2. Since the heat transfer efficiency is a function of the fouling degree and the heat exchange capacity, use a linear function for fitting to obtain the actual heat transfer efficiency η 实 =k1*X1 + k2*X2, where X1 is the fouling degree evaluation value and X2 is the heat exchange attenuation evaluation value;

[0053] Establish the observation state equation of this heat exchange system η` = A*X + e, where A is the observation matrix, the observation matrix is related to k1 and k2, X is the state variable, X = [X1 X2] T , and e is the error matrix;

[0054] Filter the state variable X through Kalman filtering to obtain the optimal estimated values of X1 and X2.

[0055] It should be noted that the Kalman filter is an algorithm that makes the obtained data continuously approach the actual data. The state variables and the observation matrix are used for data fusion to obtain a value close to the true heat transfer efficiency, which is then used as the state variable for the next process. This is then fused with the observation matrix of the next process, and so on. The final data value will be very close to the true heat transfer efficiency at the next moment.

[0056] Therefore, when the heat absorption Q on the flue gas side of the heat pipe is calculated 烟 and the heat transfer amount Q on the water side of the heat pipe 水 are obtained, the actual heat transfer efficiency η at the current moment can be calculated 实 . By setting the values of the fouling influence factor k1 and the heat transfer influence factor k2, the fouling degree evaluation value X1 and the heat transfer attenuation evaluation value X2 at the current moment can be calculated. Then, substituting each data into the observation state equation, the heat transfer efficiency η' at the next moment can be calculated, and then the optimal estimated values of X1 and X2 can be deduced. By continuously iteratively predicting and updating the state variable X, the fouling degree evaluation value X1 and the heat transfer attenuation evaluation value X2 at the next moment can be analyzed online without stopping the heat exchange system, predicting the heat transfer state of the heat pipe in the heat exchange system, enabling online analysis and early prediction, and avoiding major safety accidents.

[0057] In this embodiment, on the flue gas side, pressure sensors are respectively arranged at the inlet end and the outlet end of the flue gas to detect the pressure P of the flue gas inlet state 烟进 and the pressure P of the flue gas outlet state 烟出 . The calculated ΔP = P 烟进 - P 烟出 . ΔP is the pressure difference before and after the flue gas passes through the heat pipe. Since the fouling degree of the heat pipe will form different flue gas resistances, which in turn affect the pressure difference before and after the flue gas passes through, a flue gas resistance influence factor k3 is set. According to linear function fitting, the fouling degree evaluation value X1 = k3 * ΔP, and the observation matrix A = [k1 * k3 k2]. Adding k3 to the observation matrix means adding the factor of flue gas resistance, improving the accuracy of prediction.

[0058] In addition, according to the pressure difference ΔP of the flue gas, combined with the inlet temperature t 烟进 , the inlet flow rate G 烟进 , the outlet temperature t 烟出 , and the outlet flow rate G 烟出 , the equivalent resistance ΔP of the heat pipe on the flue gas side is calculated 折 . By comparing it with the theoretical resistance of the heat pipe on the flue gas side, the fouling situation of the heat pipe on the flue gas side can be obtained, and the fouling influence factor k1 can be calculated by conversion.

[0059] As an implementation method, if there is a leak at the bottom of the water tank and water leaks from the bottom of the water tank into the flue gas side, then the outlet flow rate G 水出 will be less than the inlet flow rate G水进 , so it is determined whether G 水出 is less than G 水进 ;

[0060] If so, it is proved that the water tank where the heat pipe is located leaks, and the leakage amount G is calculated according to the water flow difference between the water inlet and outlet 水泄 = G 水进 - G 水出 ;

[0061] Since the flue gas temperature on the flue gas side is high, the water leaking into the flue gas side will absorb heat and vaporize. According to the heat of vaporization of the cooling water and the leakage amount, the heat absorption Q of the leaked water on the flue gas side is calculated 水泄 ;

[0062] Since the cooling water leaking into the flue gas side will absorb a part of the heat of the flue gas, but this part of the heat absorption Q 水泄 will not be reflected in Q 水 , which is equivalent to Q 水 becoming smaller. At this time, Q 烟 = Q 水 + Q 水泄 , and the actual heat transfer efficiency η of the heat pipe 实 = (Q 水+ Q 水泄 ) / Q 烟 .

[0063] In the initial stage of the leakage at the beginning, the hole in the water tank is not large, the leakage amount is not much, and a small amount of water will be vaporized quickly on the flue gas side, which is not easy to observe and judge. If the heat transfer efficiency η of the heat pipe is calculated in the conventional way 实 = Q 水 / Q 烟 , assuming that Q 烟 remains unchanged, the value of Q 水 becomes smaller, and η 实 also decreases. However, in fact, the leaked water is also absorbing heat, so the actual heat transfer efficiency η of the heat pipe should be corrected to 实 = (Q 水+ Q 水泄 ) / Q 烟 . By calculating the change value of the water flow, the heat transfer efficiency under the leakage condition can be calculated more accurately to avoid misjudgment

[0064] As an implementation method, similarly, when the bottom of the water tank leaks, the water leaking into the flue gas side will form water vapor after vaporization, and the outlet flow rate G 烟出 will be greater than the inlet flow rate G 烟进 , so it is determined whether G 烟出 is greater than G 烟进 ;

[0065] If so, it is proved that the water tank where the heat pipe is located leaks, and the leakage amount G is calculated according to the difference in flue gas flow at the inlet and outlet of the flue gas side 烟泄 = G 烟出 - G 烟进 ;

[0066] Since the flue gas temperature on the flue gas side is high, the water leaking into the flue gas side will absorb heat and vaporize. According to the heat of vaporization of the cooling water and the leakage amount, the heat absorption Q of the leaked water on the flue gas side is calculated 烟泄 ;

[0067] Then Q 烟 = Q 水 + Q 烟泄 The actual heat transfer efficiency η of the heat pipe 实 = (Q 水+ Q 烟泄 ) / Q 烟 .

[0068] Compared with the previous embodiment, this embodiment detects and calculates from the flue gas side

[0069] Preferably, when G 水出 is less than G 水进 and G 烟出 is greater than G 烟进 ;

[0070] Calculate Q 均泄 = (Q 水泄 + Q 烟泄 ) / 2;

[0071] Then Q 烟 = Q 水 + Q 均泄 The actual heat transfer efficiency η of the heat pipe 实 = (Q 水+ Q 均泄 ) / Q 烟 .

[0072] Combining the advantages of the above two embodiments, detecting and technology are carried out separately from the water side and the flue gas side, averaging the obtained Q 水泄 and Q 烟泄 , and the finally obtained heat transfer efficiency η 实 is closer to the actual situation

[0073] As an embodiment, when the heat pipe is fouled and the heat exchange capacity decays, the temperature at the end of the condensation section of each heat pipe is detected, a temperature change curve is plotted for each heat pipe, and the wall temperature of each heat pipe is detected;

[0074] Combined with t 烟进 , t 烟出 , t 水进 , t 水出 , Q水 and Q 烟 to analyze the heat transfer attenuation state of each heat pipe.

[0075] Since there are multiple heat pipes in the heat transfer system at the same time and each heat pipe exists independently, the heat transfer calculation results from the flue gas side and the water side can only reflect the overall heat transfer state of all heat pipes. If it is necessary to accurately determine which specific heat pipe has attenuation, it is necessary to use an infrared temperature sensor to detect the temperature at the end of the condensation section of each heat pipe. When it is analyzed online that the heat transfer state of the heat pipe has attenuation, especially when the ash accumulation degree evaluation value X1 is lower than the set evaluation value, the infrared temperature sensor is turned on for detection, and the temperature change curve is mapped to accurately locate the abnormal heat pipe and perform point-to-point repair and replacement.

[0076] It should be noted that a lower temperature at the end of the heat pipe does not mean that the heat pipe has attenuation, and it is also possible to have a lower temperature under normal circumstances. Only when it is measured by the online analysis method of the above embodiments that the ash accumulation degree is large and the overall heat transfer effect has been affected, the infrared temperature sensor is used for detection. Further, for the convenience of temperature detection, most of the condensation section of the heat pipe is immersed in the water tank, but its end extends out of the water tank, and the infrared temperature sensor can directly measure the temperature at the end to avoid the influence of the presence of cooling water on the temperature measurement environment.

[0077] In a second aspect, an embodiment of the present application provides an electronic device, including a processor and a memory, where at least one instruction, at least one program, a code set or an instruction set is stored in the memory, and the at least one instruction, at least one program, the code set or the instruction set is loaded and executed by the processor to implement the online analysis method as described above.

[0078] The systems, devices, modules or units illustrated in the above embodiments can be specifically implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer, and the specific form of the computer can be a personal computer, a laptop computer, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email receiving and sending device, a game console, a tablet computer, a wearable device, or a combination of any several of these devices.

[0079] In a typical configuration, a computer includes one or more processors (CPUs), an input / output interface, a network interface, and a memory.

[0080] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of, for example, read-only memory (ROM) or flash memory (flash RAM). The memory is an example of a computer-readable medium.

[0081] A computer-readable medium includes permanent and non-permanent, removable and non-removable media that can implement information storage by any method or technology. The information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory, or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD), or other optical storage, magnetic cassette tapes, disk storage, quantum memory, graphene-based storage media, or other magnetic storage devices, or any other non-transmission media that can be used to store information accessible by a computing device. As defined herein, a computer-readable medium does not include transitory computer-readable media, such as modulated data signals and carrier waves.

[0082] Compared with the prior art, the above embodiments provide an online analysis method for the heat pipe heat transfer state and an electronic device, which respectively detect the states of the media on the flue gas side and the water side, and calculate Q 烟 and Q 水 , and obtain the actual heat transfer efficiency η at the current moment 实， Compare the actual heat transfer efficiency η 实 with the set heat transfer efficiency to know whether the heat transfer state of the heat pipe has decreased. By using two calculation forms of the actual heat transfer efficiency and setting the values of the fouling influence factor k1 and the heat transfer influence factor k2, the fouling degree evaluation value X1 and the heat transfer attenuation evaluation value X2 at the current moment can be calculated. Then, substituting each data into the observation state equation, the heat transfer efficiency η` at the next moment can be calculated, and then the optimal estimated values of X1 and X2 can be deduced. Using the Kalman filter to filter the state variables, the optimal estimated values of the fouling degree evaluation value and the heat transfer attenuation evaluation value can be obtained, realizing the online analysis of the heat transfer state of the heat pipe.

[0083] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0084] The above embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. An on-line analysis method for the heat pipe heat transfer state, characterized in that Including: According to the heat absorption amount Q on the flue gas side of the heat pipe 烟 and the heat transfer amount Q on the water side of the heat pipe 水 , calculate the actual heat transfer efficiency η 实 =Q 水 / Q 烟 ; When the actual heat transfer efficiency η 实 is less than the set heat exchange efficiency η 设 the following analysis is carried out: Set the dust accumulation influence factor k1 and the heat transfer influence factor k2, and use a linear function for fitting to obtain the actual heat transfer efficiency η 实 = k1*X1 + k2*X2, where X1 is the evaluation value of the dust accumulation degree and X2 is the evaluation value of the heat transfer attenuation; Establish the observation state equation η ˋ = A * X + e, where A is the observation matrix, X is the state variable, X = [X1 X2] T , and e is the error matrix; Filter the state variable X through Kalman filtering to obtain the optimal estimated values of X1 and X2; Wherein, the pressure difference before and after the flue gas passes through the heat pipe is set as ΔP, and the flue gas resistance influence factor is k3. According to linear function fitting, the fouling degree evaluation value X1 = k3 * ΔP, and the observation matrix A = [k1 * k3 k2].

2. An on-line analysis method for the heat pipe heat exchange state according to claim 1, characterized in that On the flue gas side, the inlet temperature t for detecting the inlet state of the flue gas 烟进 , and the inlet flow rate G 烟进 , and the outlet temperature t for detecting the outlet state of the flue gas 烟出 , and the outlet flow rate G 烟出 ; According to Q 烟 = C 烟 * G 烟进 * t 烟进 - C 烟 * G 烟出 * t 烟出 , calculate the heat Q absorbed by the heat pipe on the flue gas side 烟 .

3. An on-line analysis method for the heat pipe heat exchange state according to claim 2, characterized in that On the water side, the inlet temperature t for detecting the state of the circulating water inlet 水进 , and the inlet flow rate G 水进 , and the outlet temperature t for detecting the state of the circulating water outlet 水出 , and the outlet flow rate G 水出 ; According to Q 水 = C 水 * G 水出 * t 水出 - C 水 * G 水进 * t 水进 calculate the heat Q released by the heat pipe on the water side 水 .

4. An on-line analysis method for the heat pipe heat exchange state according to claim 3, characterized in that On the flue gas side, the pressure P of the flue gas inlet state is detected 烟进 , the pressure P of the flue gas outlet state is detected 烟出 , and ΔP = P 烟进 - P 烟出 ; Combined with the inlet temperature t 烟进 , the inlet flow rate G 烟进 , the outlet temperature t 烟出 , the outlet flow rate G 烟出 , calculate the reduced resistance ΔP of the heat pipes on the flue gas side 折 , compare it with the theoretical resistance of the heat pipes on the flue gas side to obtain the fouling influence factor k1.

5. An on-line analysis method for the heat pipe heat exchange state according to claim 4, characterized in that Determine G 水出 Whether it is less than G 水进 ; If so, it is proved that the water tank where the heat pipe is located leaks, and the leakage amount G is calculated according to the water flow difference between the inlet and outlet of the water side 水泄 = G 水进 - G 水出 ; Calculate the heat absorption Q of the leaked water on the flue gas side 水泄 ; Then Q 烟 = Q 水 + Q 水泄 The actual heat transfer efficiency η of the heat pipe 实 = (Q 水+ Q 水泄 ) / Q 烟 .

6. An on-line analysis method for the heat pipe heat exchange state according to claim 4, characterized in that Determine G 烟出 whether it is greater than G 烟进 ; If so, it is proved that the water tank where the heat pipe is located leaks, and the leakage amount G is calculated according to the difference in flue gas flow rates at the inlet and outlet of the flue gas side. 烟泄 = G 烟出 - G 烟进 ; Calculate the heat absorption Q of the leaked water on the flue gas side 烟泄 ; Then Q 烟 = Q 水 + Q 烟泄 The actual heat transfer efficiency η of the heat pipe 实 = (Q 水+ Q 烟泄 ) / Q 烟 .

7. An on-line analysis method for the heat pipe heat exchange state according to claim 5 or 6, characterized in that When G is satisfied simultaneously 水出 Less than G 水进 And G 烟出 Greater than G 烟进 ; Calculate Q 均泄 =(Q 水泄 +Q 烟泄 ) / 2; Then Q 烟 = Q 水 + Q 均泄 The actual heat transfer efficiency η of the heat pipe 实 = (Q 水+ Q 均泄 ) / Q 烟 .

8. An on-line analysis method for the heat pipe heat exchange state according to any one of claims 1 to 6, characterized in that Detect the temperature at the end of the condensation section of each heat pipe, draw a temperature change curve for each heat pipe, and detect the wall temperature of each heat pipe; Combined with t 烟进 and t 烟出 and t 水进 and t 水出 and Q 水 and Q 烟 , analyze the heat transfer attenuation state of each heat pipe.

9. An electronic device, characterized in that, Including a processor and a memory, wherein at least one instruction, at least one program, a code set or an instruction set is stored in the memory, and the at least one instruction, at least one program, the code set or the instruction set is loaded and executed by the processor to implement the on-line analysis method according to any one of claims 1 to 8.

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