Structural calculation method of mine ventilation air methane heat exchanger

Abstract

The invention provides a structural calculation method of a mine ventilation air methane heat exchanger, and relates to the technical field of heat exchangers, comprising: pre-training a heat exchanger design model for predicting parameters of the mine ventilation air methane heat exchanger; wherein the input parameters for training the heat exchanger design model comprise task parameters, design parameters and limiting conditions; the output parameters comprise performance parameters and structure parameters; obtaining design task data of the mine ventilation air methane heat exchanger; inputting the design task data into the heat exchanger design model to obtain a plurality of groups of primary heat exchanger parameter sets; and screening the plurality of groups of primary heat exchanger parameter sets by taking the function relationship of the heat transfer coefficient, the fresh air pressure drop and the total mass of the heat exchange tube with respect to the structural parameters as objective functions, and determining a design scheme of the mine ventilation air methane heat exchanger. According to the scheme, performance and cost factors are comprehensively considered, and the practicability of the designed ventilation air methane heat exchanger can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of heat exchangers, and in particular to a structural calculation method for a mine exhaust air heat exchanger. Background Art

[0002] Mines are the starting point for raw materials for energy and chemical companies and are an indispensable link in this industrial production chain. Since mines are far away from the main production area, it is difficult to obtain heat from the main production area to meet the heat demand of the air intake wellhead in the cold winter without ice. However, in mining operations, the operation of coal mining machinery is accompanied by the generation of a large amount of waste heat, which is discharged to the outside through the exhaust air system. The exhaust air flow is huge and the temperature is low, generally between 10°C and 20°C.

[0003] In order to meet the demand of preventing the air inlet wellhead from freezing in cold winter, a mine exhaust air heat exchanger has emerged, which uses the mine's own waste heat for antifreeze of the mine wellhead. This heat exchanger has the advantages of low operating cost, environmental friendliness and simple maintenance. However, as a non-standard product, the cycle from design task to design scheme of heat exchanger is relatively long, especially when the design method of traversing all possible structural arrangements and then finding the optimal solution by comparison is adopted, it will take a lot of time to use automatic calculation software. Moreover, based on the existing intelligent design scheme of exhaust air heat exchanger, only the theoretical high performance requirements are pursued, while in practice, cost factors are also an important consideration in heat exchanger design, which leads to the poor practicality of this purely theoretical high performance exhaust air heat exchanger design scheme. Summary of the invention

[0004] In view of this, in order to address the above shortcomings, it is necessary to propose a structural calculation method for mine exhaust air heat exchangers that comprehensively considers performance and cost factors, so as to improve the practicality of the designed exhaust air heat exchanger.

[0005] In a first aspect, the present invention provides a method for calculating the structure of a mine exhaust air heat exchanger, comprising:

[0006] Pre-training a heat exchanger design model for predicting parameters of a mine exhaust air heat exchanger; wherein the input parameters for training the heat exchanger design model include: task parameters, design parameters and constraints; and the output parameters include: performance parameters and structural parameters;

[0007] Obtain design task data for mine exhaust air heat exchanger;

[0008] Inputting the design task data into the heat exchanger design model to obtain several sets of primary heat exchanger parameter sets;

[0009] The functional relationships among heat transfer coefficient, fresh air pressure drop and total mass of heat exchange tubes and structural parameters are respectively used as objective functions, and several groups of primary heat exchanger parameter sets are screened to determine the design scheme of the mine exhaust air heat exchanger structure.

[0010] Preferably, the pre-trained heat exchanger design model for predicting parameters of a mine exhaust air heat exchanger comprises:

[0011] The limit range and change step value of the input parameters are set in the mine exhaust air heat exchanger calculation software, the output parameters corresponding to each input parameter combination are calculated, and the combination of each group of input parameters and output parameters is used to form a primary sample data set for training the heat exchanger design model;

[0012] Performing feature selection on the primary sample data set to select input parameters and output parameters that have a significant impact on the prediction performance of the model, thereby obtaining a secondary sample data set;

[0013] Performing feature processing on the secondary sample data set through correlation analysis and normalization operations to obtain a sample training data set;

[0014] The sample training data set is used to perform model training to obtain the heat exchanger design model.

[0015] Preferably, the using the sample training data set to perform model training includes:

[0016] Model training is performed using the sample training data set based on but not limited to one of a fully connected neural network, a random forest model, and a long short-term memory network.

[0017] Preferably, during the model training process, the hyperparameters of the model are optimized based on, but not limited to, utilizing one of a Bayesian optimization algorithm, a grid search algorithm, and a multi-objective optimization algorithm.

[0018] Preferably,

[0019] The task parameters include: exhaust air inlet and outlet temperature T, exhaust air inlet and outlet humidity Rh_T, fresh air inlet and outlet temperature t, fresh air inlet and outlet humidity Rh_t, exhaust air volume q m1 , fresh air volume q m2 , atmospheric pressure value P at the project design site;

[0020] The design parameters include: pipe diameter D, wall thickness d, length L and material;

[0021] The limiting conditions include: the ventilation air pressure drop ΔP 1 ;

[0022] The performance parameters include: exhaust air flow rate u 1 , fresh air flow rate u 2, heat transfer coefficient K, exhaust air pressure drop ΔP 1 , fresh air pressure drop ΔP 2 , total mass of heat exchange tube G, heat transfer area A, heat load Q, and heat supplement ΔQ;

[0023] The structural parameters include: transverse tube center distance s 1 , vertical center distance of heat exchange tubes s 2 , number of horizontal tubes in a single module a, number of vertical tubes in a single module b, number of horizontal modules B, number of vertical modules C, number of longitudinal modules LG, horizontal dimension of a single module e, vertical dimension of a single module h, overall horizontal dimension of the heat exchanger E, overall vertical dimension of the heat exchanger H, overall length dimension of the heat exchanger LT.

[0024] Preferably, the screening of the plurality of sets of primary heat exchanger parameter sets to determine the design scheme of the mine exhaust air heat exchanger comprises:

[0025] Taking the functional relationship between the heat transfer coefficient, the fresh air pressure drop and the total mass of the heat exchange tube with respect to the structural parameters as the objective function, the plurality of sets of primary heat exchanger parameter sets are screened to obtain a plurality of sets of secondary heat exchanger parameter sets;

[0026] Based on the prediction errors of heat transfer coefficient, exhaust air pressure drop and fresh air pressure drop corresponding to each set of secondary heat exchanger parameter sets, the secondary heat exchanger parameter sets are screened and the design scheme of mine exhaust air heat exchanger is output;

[0027] A two-dimensional construction drawing is generated based on the structural parameters of the design solution.

[0028] Preferably,

[0029] Construct the objective function of heat transfer coefficient with respect to structural parameters, including:

[0030] Using TableCurve 3D curve fitting software, the heat transfer coefficient K and exhaust air velocity u are fitted 1 and fresh air flow rate u 2 The functional relationship is obtained by converting the flow rate into flow rate and structural parameters, and the objective function of the heat transfer coefficient with respect to the structural parameters is obtained as follows:

[0031]

[0032] Among them, x 1 、x 2 、x 3 、x 4 、x 5 、x 6 、x 7 、x 8 、x 9 、x 10 are all constants;

[0033] and / or,

[0034] The objective function of fresh air pressure drop with respect to structural parameters is expressed as follows:

[0035]

[0036] and / or,

[0037] The objective function of the total mass of the heat exchange tube with respect to the structural parameters is expressed as follows:

[0038]

[0039] Among them, λ is used to characterize the friction coefficient of fresh air in the heat exchange tube, and ρ is used to characterize the density of the heat exchange tube material.

[0040] Preferably, the secondary heat exchanger parameter set is screened based on the predicted errors of the heat transfer coefficient, exhaust air pressure drop and fresh air pressure drop corresponding to each set of secondary heat exchanger parameter sets, and a design scheme of the mine exhaust air heat exchanger structure is output, including:

[0041] For each set of secondary heat exchanger parameters, perform the following steps:

[0042] S1: Input the input parameters in the current secondary heat exchanger parameter set into the mine exhaust air heat exchanger calculation software to obtain the theoretical heat transfer coefficient, theoretical exhaust air pressure drop and theoretical fresh air pressure drop;

[0043] S2: Determine whether the relative error between the predicted heat transfer coefficient of the current secondary heat exchanger parameter set and the theoretical heat transfer coefficient is less than a preset error threshold; if not, remove the secondary heat exchanger parameter set; if yes, execute S3;

[0044] S3: Determine whether the error between the predicted exhaust air pressure drop of the current heat exchanger parameter set and the theoretical exhaust air pressure drop is less than a preset error threshold; if not, classify the secondary heat exchanger parameter set into the third type of solution; if yes, execute S4;

[0045] S4: determining whether the error between the predicted fresh air pressure drop of the current heat exchanger parameter set and the theoretical fresh air pressure drop is less than a preset error threshold; if not, classifying the secondary heat exchanger parameter set into the second type of solution; if yes, executing S5;

[0046] S5: classifying the current secondary heat exchanger parameter set into the first type of solution, and replacing the predicted performance parameter value in the current secondary heat exchanger parameter set with the theoretical performance parameter value obtained by the mine exhaust air heat exchanger calculation software;

[0047] After the selection of each set of secondary heat exchanger parameters is completed, perform the following operations:

[0048] Prioritize the output of the first type of solutions;

[0049] If the first type of solution is an empty set, the second type of solution is output and a prompt is given to recalculate the fresh air pressure drop;

[0050] If both the first and second schemes are empty sets, the third scheme will be output, and a prompt will be given to recalculate the fresh air pressure drop and the exhaust air pressure drop;

[0051] If the first, second and third types of solutions are all empty sets, a prompt to check the units of the input parameters and their rationality will be output.

[0052] Preferably, when training the heat exchanger design model, the functional relationship between the floor area and the structural parameters, and the functional relationship between the total height of the equipment and the structural parameters are further used as constraint conditions for training; wherein the functional relationship between the floor area and the total height of the equipment and the structural parameters is expressed as follows:

[0053] S=(s 1 ×a+d+0.03×2)×B×(L×2+0.7)

[0054] HI=(s 2 ×b+d+0.06×2)×C

[0055] Among them, S is used to represent the floor area, and HI is used to represent the total height of the equipment.

[0056] In a second aspect, the present invention provides a computing device, including a memory and a processor, wherein executable code is stored in the memory, and when the processor executes the executable code, any method described in the first aspect is implemented.

[0057] It can be seen from the above technical scheme that in the structural calculation method of the mine exhaust air heat exchanger provided by the embodiment of the present invention, firstly, the task parameters, design parameters and constraints are used as input parameters, and the heat exchanger design model is pre-trained with performance parameters and structural parameters, and then the design task data of the mine heat exchanger is obtained and input into the heat exchanger design model to obtain several sets of primary heat exchanger parameter sets; finally, the functional relationship between the heat transfer coefficient, the fresh air pressure drop and the total mass of the heat exchange tube on the structural parameters is used as the objective function to screen the primary tube parameter set, so as to determine the design scheme of the mine exhaust air heat exchanger. It can be seen that this scheme predicts parameters through the model, which can greatly save the design time of the exhaust air heat exchanger compared with the existing scheme that uses several formulas to calculate the final heat exchanger parameters step by step. Moreover, this scheme uses the functional relationship between the heat transfer coefficient, the fresh air pressure drop and the total mass of the heat exchange tube on the structural parameters as the objective function to screen the primary heat exchanger parameter set, so that the performance and cost of the designed heat exchanger can be balanced, so that the designed exhaust air heat exchanger has higher practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 A flow chart of a method for calculating the structure of a mine exhaust air heat exchanger provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0059] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0060] like Figure 1 As shown, an embodiment of the present invention provides a method for calculating the structure of a mine exhaust air heat exchanger, which may include the following steps:

[0061] Step 10: pre-training a heat exchanger design model for predicting parameters of a mine exhaust air heat exchanger; wherein the input parameters for training the heat exchanger design model include: task parameters, design parameters and constraints; and the output parameters include: performance parameters and structural parameters;

[0062] Step 20: Obtain design task data of the mine exhaust air heat exchanger;

[0063] Step 30: inputting the design task data into the heat exchanger design model to obtain several sets of primary heat exchanger parameter sets;

[0064] Step 40: Taking the functional relationship between the heat transfer coefficient, the fresh air pressure drop and the total mass of the heat exchange tube with respect to the structural parameters as the objective function, the plurality of sets of primary heat exchanger parameter sets are screened to determine the design scheme of the mine exhaust air heat exchanger structure.

[0065] In this embodiment, parameter prediction is considered through the model, which can greatly save the design time of the exhaust air heat exchanger compared to the existing solution that uses several formulas to calculate the final heat exchanger parameters step by step. In addition, this solution uses the functional relationship of the heat transfer coefficient, the fresh air pressure drop and the total mass of the heat exchange tube with respect to the structural parameters as the objective function to screen the primary heat exchanger parameter set, so that the performance and cost of the designed heat exchanger can be balanced, so that the designed exhaust air heat exchanger has higher practicality.

[0066] For step 10, a heat exchanger design model for predicting parameters of a mine exhaust air heat exchanger is pre-trained;

[0067] In this step, consider taking the task parameters, design parameters and constraints as input parameters, and taking the performance parameters and structure parameters as output parameters to train the heat exchanger design model, so as to predict the parameters of the mine exhaust air heat exchanger. Specifically, step 10 can be implemented as follows:

[0068] Step 101: setting the limit range and change step value of the input parameters in the mine exhaust air heat exchanger calculation software, calculating the output parameters corresponding to each input parameter combination, and using the combination of each group of input parameters and output parameters to form a primary sample data set for training the heat exchanger design model;

[0069] Step 102: performing feature selection on the primary sample data set to select input parameters and output parameters that have a significant impact on the model prediction performance, thereby obtaining a secondary sample data set;

[0070] Step 103: performing feature processing on the secondary sample data set through correlation analysis and normalization operations to obtain a sample training data set;

[0071] Step 104: Perform model training using the sample training data set to obtain the heat exchanger design model.

[0072] For step 101, consider generating a primary sample data set through heat exchanger calculation software, for example, the Phecal plate heat exchanger calculation software tool can be used. As shown in Table 1, the tool sets multiple variables including exhaust air volume, exhaust air inlet temperature, exhaust air inlet humidity, etc., and each variable sets a start value, an end value, and a step value. Through the set variables, the tool can generate approximately 3.36 million design schemes, which basically cover all design requirements. As shown in Table 2 below, the generated design schemes are subdivided into categories such as task parameters, structural parameters, design parameters, and performance parameters. The production process of this data set is not only highly automated, but also can effectively support subsequent data analysis and model training.

[0073] Table 1 Variable combination table for generating sequential scheme data set

[0074]

[0075] Table 2 Parameter combination table of generated scheme data set

[0076]

[0077] For step 102, it is used to perform feature selection on the primary sample data set to screen out the input parameters and output parameters that significantly affect the model prediction performance. Specifically, based on engineering practice and theoretical analysis, feature selection can be performed through specific rules. For example, if a certain performance parameter can be obtained through a linear combination of several other parameters, the parameter can be eliminated. For another example, objectively specified constant parameters, such as exhaust air outlet humidity, can be directly set as constants. As shown in Table 3 below, the input and output parameters after feature screening are the basis for subsequent model training.

[0078] Table 3 Input and output of the scheme data set

[0079]

[0080] In one embodiment, the task parameters may include: exhaust air inlet and outlet temperature T, exhaust air inlet and outlet humidity Rh_T, fresh air inlet and outlet temperature t, fresh air inlet and outlet humidity Rh_t, exhaust air volume q m1 , fresh air volume q m2 , atmospheric pressure value P at the project design site;

[0081] The design parameters may include: pipe diameter D, wall thickness d, length L and material;

[0082] The limiting conditions may include: the ventilation air pressure drop ΔP 1 ;

[0083] The performance parameters may include: exhaust air flow rate u 1 , fresh air flow rate u 2 , heat transfer coefficient K, exhaust air pressure drop ΔP 1 , fresh air pressure drop ΔP 2 , total mass of heat exchange tube G, heat transfer area A, heat load Q, and heat supplement ΔQ;

[0084] The structural parameters may include: transverse tube center distance s 1 , vertical center distance of heat exchange tubes s 2 , number of horizontal tubes in a single module a, number of vertical tubes in a single module b, number of horizontal modules B, number of vertical modules C, number of longitudinal modules LG, horizontal dimension of a single module e, vertical dimension of a single module h, overall horizontal dimension of the heat exchanger E, overall vertical dimension of the heat exchanger H, overall length dimension of the heat exchanger LT.

[0085] For step 103, it considers processing the distribution state and scale of the data. Specifically, feature engineering can be performed using two methods: correlation analysis and feature transformation. Correlation analysis can evaluate the strength of the linear relationship between individual variables by calculating the Pearson correlation coefficient, helping to further understand the data characteristics. Feature transformation can include data standardization and logarithmic transformation, etc., which aims to improve the distribution state and scale of the data to make it more suitable for model training.

[0086] For step 104, it is considered to use the sample training data set obtained after processing to perform model training, so as to obtain a heat exchanger design model. Specifically, it is considered to perform model training based on a fully connected neural network, a random forest model, or a long short-term memory network, and during the training process, the hyperparameters of the model are optimized using a Bayesian optimization algorithm or a grid search algorithm + a dynamic learning rate, or a multi-objective optimization algorithm. Of course, the model based on which the heat exchanger design model is trained can also include other neural networks, and the optimization algorithm for optimizing the model hyperparameters can also include other optimization algorithms.

[0087] In a preferred implementation, the hyperparameters of the long short-term memory network can be optimized by a Bayesian optimization algorithm, and the heat exchanger design model can be trained. The batch size of the model training is 32, the learning rate is 0.0062, the number of layers is 3, and the number of neurons in each layer is 49. The efficiency of the trained heat exchanger design model is compared with that of traditional automated calculation tools. The results show that when processing the same data, the time required for this solution is 0.2% of that of traditional tools, which significantly improves the efficiency of heat exchanger design. The comparison results are shown in Table 4 below.

[0088] Table 4 Operation time of heat exchanger design model and automated design software

[0089]

[0090] In addition, although the constraints of the model are determined by the structural parameters, in actual design, factors such as the footprint and height of the equipment need to be considered. For example, most mine units are located in mountainous areas and have a large plant area. However, this does not mean that the area limitation can be ignored in the design of heat exchangers. If the heat exchanger occupies too much area, it may affect the normal operation of the traffic and other facilities in the mine plant area. Therefore, when designing a heat exchanger, engineers need to set the maximum footprint as a constraint of the design scheme according to the actual situation on site. Similarly, the reasons for limiting the total height of the heat exchanger equipment include considerations such as the safety of high-altitude operations and the influence of wind loads. In an environment such as a mountain mine, the risks of high-altitude operations are extremely high due to the complexity of the terrain and the limitation of space. As the height of the equipment increases, its influence by wind loads will become more significant. Wind can cause additional horizontal loads on the equipment, which requires that the design should not only consider the structural strength of the equipment, but also its stability. When designing a heat exchanger, engineers need to set the maximum equipment height as a constraint of the design scheme. Therefore, in the process of model training, the functional relationship between the floor area and the structural parameters, as well as the functional relationship between the total height of the equipment and the structural parameters are considered to be further trained as constraint conditions; among them, the functional relationship between the floor area and the total height of the equipment and the structural parameters is expressed as follows:

[0091] S=(s 1×a+d+0.03×2)×B×(L×2+0.7)

[0092] HI=(s 2 ×b+d+0.06×2)×C

[0093] Among them, S is used to represent the floor area, and HI is used to represent the total height of the equipment.

[0094] For step 20, the design task data of the mine exhaust air heat exchanger is obtained;

[0095] This step is used to obtain the design task data of the mine exhaust air heat exchanger, which may include exhaust air inlet and outlet temperature T, exhaust air inlet and outlet humidity Rh_T, fresh air inlet and outlet temperature t, fresh air inlet and outlet humidity Rh_t, exhaust air volume q m1 , fresh air volume q m2 , the atmospheric pressure value P of the project design site, the pipe diameter D, wall thickness d, length L and material of the heat exchange tube to be used, and the maximum allowable exhaust air pressure drop ΔP 1 .

[0096] For step 30, the design task data is input into the heat exchanger design model to obtain several sets of primary heat exchanger parameter sets;

[0097] In this step, the design task data is input into the trained heat exchanger design model to calculate the structural parameters and performance parameters of the exhaust air pressure drop that does not exceed the maximum allowable exhaust air pressure drop. A set of design parameters, task parameters, structural parameters and performance parameters constitute a set of primary heat exchanger parameter sets. Among them, the structural parameters can include the transverse tube center distance s 1 , vertical center distance of heat exchange tubes s 2 , single module horizontal tube number a, single module vertical tube number b, horizontal module number B, vertical module number C, longitudinal module number LG, single module horizontal dimension e, single module vertical dimension h, heat exchanger overall horizontal dimension E, heat exchanger overall vertical dimension H, heat exchanger overall length dimension LT; performance parameters may include exhaust air flow rate u 1 , fresh air flow rate u 2 , heat transfer coefficient K, exhaust air pressure drop ΔP 1 , fresh air pressure drop ΔP 2 , total mass G of the heat exchange tube, heat transfer area A, heat load Q, heat supplement ΔQ, etc.

[0098] For step 40, the functional relationship between the heat transfer coefficient, the fresh air pressure drop and the total mass of the heat exchange tube and the structural parameters is used as the objective function, and the plurality of sets of primary heat exchanger parameter sets are screened to determine the design scheme of the mine exhaust air heat exchanger.

[0099] In this step, considering that in actual applications, a heat exchanger can only be practical if its performance and cost are relatively balanced. Therefore, the structural parameters of the heat exchanger are optimized using the functional relationship between the heat transfer coefficient, the fresh air pressure drop, and the total mass of the heat exchange tube with respect to the structural parameters as the objective function, that is, to select a design solution that is both economical and efficient from the primary heat exchanger parameter set. Specifically, step 40 can be implemented by the following steps:

[0100] Step 401: taking the functional relationship between the heat transfer coefficient, the fresh air pressure drop and the total mass of the heat exchange tube with respect to the structural parameters as the objective function, screening the plurality of sets of primary heat exchanger parameter sets to obtain a plurality of sets of secondary heat exchanger parameter sets;

[0101] Step 402: based on the predicted errors of the heat transfer coefficient, exhaust air pressure drop and fresh air pressure drop corresponding to each set of secondary heat exchanger parameter sets, the secondary heat exchanger parameter sets are screened, and a design scheme of the mine exhaust air heat exchanger is output;

[0102] Step 403: Generate a two-dimensional construction drawing based on the structural parameters of the design solution.

[0103] For step 401, it is considered that the heat transfer coefficient K, the fresh air pressure drop ΔP 2 The objective function is formed by the total mass G of the heat exchange tube. These objective functions have a functional relationship with the structural parameters. Specifically, the objective function of the heat transfer coefficient with respect to the structural parameters may include:

[0104] Using TableCurve 3D curve fitting software, the heat transfer coefficient K and exhaust air velocity u are fitted 1 and fresh air flow rate u 2 The functional relationship is obtained by converting the flow rate into flow rate and structural parameters, and the objective function of the heat transfer coefficient with respect to the structural parameters is obtained as follows:

[0105]

[0106] The fresh air pressure drop is expressed by structural parameters, and the fresh air volume is given by the task parameters. The material density and friction coefficient of the heat exchange tube also need to be considered comprehensively. In order to make the inputs of the three objective functions the same, the objective function of the fresh air pressure drop with respect to the structural parameters can be expressed as follows:

[0107]

[0108] The total mass of the heat exchange tube can be directly expressed by the structural parameters. The different material densities of the heat exchange tubes make the total mass of the heat exchange tubes different under the same number of heat exchange tubes. In order to make the inputs of the three objective functions the same, the objective function of the total mass of the heat exchange tubes with respect to the structural parameters can be expressed as follows:

[0109]

[0110] Among them, λ is used to characterize the friction coefficient of fresh air in the heat exchange tube, and ρ is used to characterize the density of the heat exchange tube material.

[0111] To solve the maximum heat transfer coefficient, the minimum fresh air pressure drop and the minimum heat exchange tube mass, the optimal solution can be solved based on the NSGA-II algorithm and the multi-objective particle swarm optimization algorithm MOPSO.

[0112] For step 402, the secondary heat exchanger parameter set is screened based on the prediction errors of the heat transfer coefficient, exhaust air pressure drop and fresh air pressure drop corresponding to each set of secondary heat exchanger parameter sets, and the design scheme of the mine exhaust air heat exchanger is output, which can be specifically implemented in the following ways:

[0113] For each set of secondary heat exchanger parameters, perform the following steps:

[0114] S1: Input the input parameters in the current secondary heat exchanger parameter set into the mine exhaust air heat exchanger calculation software to obtain the theoretical heat transfer coefficient, theoretical exhaust air pressure drop and theoretical fresh air pressure drop;

[0115] S2: Determine whether the relative error between the predicted heat transfer coefficient of the current secondary heat exchanger parameter set and the theoretical heat transfer coefficient is less than a preset error threshold; if not, remove the secondary heat exchanger parameter set; if yes, execute S3;

[0116] S3: Determine whether the error between the predicted exhaust air pressure drop of the current heat exchanger parameter set and the theoretical exhaust air pressure drop is less than a preset error threshold; if not, classify the secondary heat exchanger parameter set into the third type of solution; if yes, execute S4;

[0117] S4: determining whether the error between the predicted fresh air pressure drop of the current heat exchanger parameter set and the theoretical fresh air pressure drop is less than a preset error threshold; if not, classifying the secondary heat exchanger parameter set into the second type of solution; if yes, executing S5;

[0118] S5: classifying the current secondary heat exchanger parameter set into the first type of solution, and replacing the predicted performance parameter value in the current secondary heat exchanger parameter set with the theoretical performance parameter value obtained by the mine exhaust air heat exchanger calculation software;

[0119] After the selection of each set of secondary heat exchanger parameters is completed, perform the following operations:

[0120] Prioritize the output of the first type of solutions;

[0121] If the first type of solution is an empty set, the second type of solution is output and a prompt is given to recalculate the fresh air pressure drop;

[0122] If both the first and second schemes are empty sets, the third scheme will be output, and a prompt will be given to recalculate the fresh air pressure drop and the exhaust air pressure drop;

[0123] If the first, second and third types of solutions are all empty sets, a prompt to check the units of the input parameters and their rationality will be output.

[0124] The preset error threshold may be 5%.

[0125] For step 403, it is considered to generate a two-dimensional construction drawing based on the structural parameters of the design scheme. The output single scheme may include a scheme number, a structural layout scheme and its corresponding actual calculation performance parameters; after the staff determines the final scheme, they select the corresponding scheme number and generate a two-dimensional construction drawing based on the structural parameters.

[0126] Of course, in one embodiment, the heat exchanger design model and objective function screening model based on this solution can be integrated into a GUI visual input interface to realize the automation and intelligence of heat exchanger design. The system is deployed under the Python Flask framework, using .pth file import and its learning model and Python script to execute the objective function screening model, creating a complete user interaction process, allowing engineers to easily input the design task tree and actual requirements.

[0127] The present specification also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed in a computer, the computer is caused to execute a method in any one of the embodiments in the specification.

[0128] The present specification also provides a computing device, including a memory and a processor, wherein executable codes are stored in the memory, and when the processor executes the executable codes, a method in any embodiment of the present specification is implemented.

[0129] Since the device embodiments provided by the present invention are based on the same inventive concept as the method embodiments of this specification, the specific contents can be found in the description of the method embodiments of this specification and will not be repeated here.

[0130] The modules or units in the device of the embodiment of the present invention can be combined, divided and deleted according to actual needs. The above disclosure is only the preferred embodiment of the present invention, and of course it cannot be used to limit the scope of the rights of the present invention. Those skilled in the art can understand that all or part of the processes of the above embodiment are implemented, and the equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A structural calculation method for a mine exhaust air heat exchanger, characterized in that: include: Pre-training a heat exchanger design model for predicting parameters of a mine exhaust air heat exchanger; wherein the input parameters for training the heat exchanger design model include: task parameters, design parameters and constraints; and the output parameters include: performance parameters and structural parameters; Obtain design task data for mine exhaust air heat exchanger; Inputting the design task data into the heat exchanger design model to obtain several sets of primary heat exchanger parameter sets; The functional relationships among heat transfer coefficient, fresh air pressure drop and total mass of heat exchange tubes and structural parameters are respectively used as objective functions, and several groups of primary heat exchanger parameter sets are screened to determine the design scheme of the mine exhaust air heat exchanger structure.

2. The structural calculation method of the mine exhaust air heat exchanger according to claim 1 is characterized in that: The pre-trained heat exchanger design model for predicting parameters of a mine exhaust air heat exchanger includes: The limit range and change step value of the input parameters are set in the mine exhaust air heat exchanger calculation software, the output parameters corresponding to each input parameter combination are calculated, and the combination of each group of input parameters and output parameters is used to form a primary sample data set for training the heat exchanger design model; Performing feature selection on the primary sample data set to select input parameters and output parameters that have a significant impact on the prediction performance of the model, thereby obtaining a secondary sample data set; Performing feature processing on the secondary sample data set through correlation analysis and normalization operations to obtain a sample training data set; The sample training data set is used to perform model training to obtain the heat exchanger design model.

3. The structural calculation method of the mine exhaust air heat exchanger according to claim 2 is characterized in that: The using the sample training data set to perform model training includes: Model training is performed using the sample training data set based on but not limited to one of a fully connected neural network, a random forest model, and a long short-term memory network.

4. The structural calculation method of the mine exhaust air heat exchanger according to claim 3 is characterized in that: During the model training process, the hyperparameters of the model are optimized based on, but not limited to, using one of a Bayesian optimization algorithm, a grid search algorithm, and a multi-objective optimization algorithm.

5. The structural calculation method of the mine exhaust air heat exchanger according to claim 1 is characterized in that: The task parameters include: exhaust air inlet and outlet temperature T, exhaust air inlet and outlet humidity Rh_T, fresh air inlet and outlet temperature t, fresh air inlet and outlet humidity Rh_t, exhaust air volume q m1 , fresh air volume q m2 , atmospheric pressure value P at the project design site; The design parameters include: pipe diameter D, wall thickness d, length L and material; The limiting conditions include: the exhaust air pressure drop ΔP1; The performance parameters include: exhaust air velocity u1, fresh air velocity u2, heat transfer coefficient K, fresh air pressure drop ΔP2, total mass of heat exchange tube G, heat transfer area A, heat load Q, and supplementary heat ΔQ; The structural parameters include: transverse tube center distance s1, vertical tube center distance s2 of heat exchange tubes, number of transverse tubes a of a single module, number of vertical tubes b of a single module, number of transverse modules B, number of vertical modules C, number of longitudinal modules LG, transverse dimension e of a single module, vertical dimension h of a single module, overall transverse dimension E of the heat exchanger, overall vertical dimension H of the heat exchanger, and overall length dimension LT of the heat exchanger.

6. The structural calculation method of the mine exhaust air heat exchanger according to claim 5 is characterized in that: The method of screening the plurality of sets of primary heat exchanger parameter sets to determine the design scheme of the mine exhaust air heat exchanger structure includes: Taking the functional relationship between the heat transfer coefficient, the fresh air pressure drop and the total mass of the heat exchange tube with respect to the structural parameters as the objective function, the plurality of sets of primary heat exchanger parameter sets are screened to obtain a plurality of sets of secondary heat exchanger parameter sets; Based on the prediction errors of heat transfer coefficient, exhaust air pressure drop and fresh air pressure drop corresponding to each set of secondary heat exchanger parameter sets, the secondary heat exchanger parameter sets are screened and the design scheme of mine exhaust air heat exchanger is output; A two-dimensional construction drawing is generated based on the structural parameters of the design solution.

7. The structural calculation method of the mine exhaust air heat exchanger according to claim 6 is characterized in that: Construct the objective function of heat transfer coefficient with respect to structural parameters, including: TableCurve 3D curve fitting software is used to fit the functional relationship between the heat transfer coefficient K and the exhaust air flow rate u1 and the fresh air flow rate u2, and the flow rate is converted into flow rate and structural parameters to obtain the following objective function of the heat transfer coefficient with respect to the structural parameters: Among them, x1, x2, x3, x4, x5, x6, x7, x8, x9, x 10 are all constants; and / or, The objective function of fresh air pressure drop with respect to structural parameters is expressed as follows: and / or, The objective function of the total mass of the heat exchange tube with respect to the structural parameters is expressed as follows: Among them, λ is used to characterize the friction coefficient of fresh air in the heat exchange tube, and ρ is used to characterize the density of the heat exchange tube material.

8. The structural calculation method of the mine exhaust air heat exchanger according to claim 6 is characterized in that: The secondary heat exchanger parameter set is screened based on the predicted errors of the heat transfer coefficient, exhaust air pressure drop and fresh air pressure drop corresponding to each set of secondary heat exchanger parameter sets, and a design scheme of the mine exhaust air heat exchanger is output, including: For each set of secondary heat exchanger parameters, perform the following steps: S1: Input the input parameters in the current secondary heat exchanger parameter set into the mine exhaust air heat exchanger calculation software to obtain the theoretical heat transfer coefficient, theoretical exhaust air pressure drop and theoretical fresh air pressure drop; S2: Determine whether the relative error between the predicted heat transfer coefficient of the current secondary heat exchanger parameter set and the theoretical heat transfer coefficient is less than a preset error threshold; if not, remove the secondary heat exchanger parameter set; if yes, execute S3; S3: Determine whether the error between the predicted exhaust air pressure drop of the current heat exchanger parameter set and the theoretical exhaust air pressure drop is less than a preset error threshold; if not, classify the secondary heat exchanger parameter set into the third type of solution; if yes, execute S4; S4: determining whether the error between the predicted fresh air pressure drop of the current heat exchanger parameter set and the theoretical fresh air pressure drop is less than a preset error threshold; if not, classifying the secondary heat exchanger parameter set into the second type of solution; if yes, executing S5; S5: classifying the current secondary heat exchanger parameter set into the first type of solution, and replacing the predicted performance parameter value in the current secondary heat exchanger parameter set with the theoretical performance parameter value obtained by the mine exhaust air heat exchanger calculation software; After the selection of each set of secondary heat exchanger parameters is completed, perform the following operations: Prioritize the output of the first type of solutions; If the first type of solution is an empty set, the second type of solution is output and a prompt is given to recalculate the fresh air pressure drop; If both the first and second schemes are empty sets, the third scheme will be output, and a prompt will be given to recalculate the fresh air pressure drop and the exhaust air pressure drop; If the first, second and third types of solutions are all empty sets, a prompt to check the units of the input parameters and their rationality will be output.

9. The structural calculation method of the mine exhaust air heat exchanger according to claim 5, characterized in that: When training the heat exchanger design model, the functional relationship between the floor area and the structural parameters, and the functional relationship between the total height of the equipment and the structural parameters are further trained as constraint conditions; wherein the functional relationship between the floor area and the total height of the equipment and the structural parameters is expressed as follows: S=(s1×a+d+0.03×2)×B×(L×2+0.7) HI=(s2×b+d+0.06×2)×C Among them, S is used to represent the floor area, and HI is used to represent the total height of the equipment.

10. A computing device, comprising a memory and a processor, wherein the memory stores executable codes, and when the processor executes the executable codes, the method according to any one of claims 1 to 9 is implemented.

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