A control method and system for a zoned reheat condenser

Abstract

The present application belongs to the technical field of condenser control, and provides a control method and system for a zoned reheat condenser, comprising: uniformly dividing each flow channel of the zoned reheat condenser into multiple regions, respectively, backstepping the region heat exchange intensity through the temperature data and pressure data collected in each region, and identifying the high-turbulence region and low-pressure-drop region in each flow channel; based on the high-turbulence region and low-pressure-drop region in each flow channel, evaluating the optimization requirement of the flow channel through the matching and turbulence uniformity of the high-turbulence region and low-pressure-drop region; extracting the high-flow channel of the optimization requirement for the same category integration, obtaining the high-flow channel group of the optimization requirement, and extracting the adjacent flow channel combination in the high-flow channel group of the optimization requirement, and analyzing the influence degree of the adjacent flow channel combination; if the influence degree is high, the unidirectional strong coupling flow channel is extracted. Thus, the optimization measures are targeted at the local overheating, flow short circuit and the like caused by non-uniform flow, so as to realize the objectives of improving the condenser efficiency and reducing the risk.

Description

Technical Field

[0001] This invention belongs to the field of condenser control technology, specifically a control method and system for a zoned reheat condenser. Background Technology

[0002] The condenser is the core heat exchange device of the refrigeration system. Its core function is to condense the high-temperature and high-pressure gaseous refrigerant into a liquid state through a cooling medium (such as water or air). This process is accompanied by the release of a large amount of heat, so the temperature of the condenser is usually high. In the design of large condensers, the zoning function is often used to improve the heat exchange efficiency.

[0003] Plate condensers utilize corrugated plates to form multi-channel flow paths, increasing turbulence and improving heat transfer coefficients through fluid partitioning. However, non-uniform flow often exists in the flow paths, i.e., high turbulence zones and low pressure drop zones coexist. This may lead to unbalanced thermal resistance distribution causing local overheating, uneven pressure drop increasing pumping energy consumption, flow short-circuiting forming heat transfer dead zones, material fatigue and sealing failure, which in turn reduce heat exchange efficiency and increase operational risks.

[0004] Therefore, the present invention provides a control method and system for a zoned reheat condenser. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0006] The technical solution adopted by this invention to solve its technical problem is: a control method for a zoned reheat condenser, comprising:

[0007] Each flow channel of the partitioned reheat condenser is evenly divided into multiple regions. By collecting temperature and pressure data of each region, the heat transfer intensity of the region is inferred, and the high turbulence region and low pressure drop region in each flow channel are identified.

[0008] Based on the high turbulence region and low pressure drop region within each flow channel, the optimization requirements of the flow channel are evaluated by assessing the matching and turbulence uniformity between the high turbulence region and the low pressure drop region.

[0009] Extract high-demand flow channels and integrate them into the same category to obtain high-demand flow channel groups. Then, extract adjacent flow channel combinations in the high-demand flow channel groups and analyze the degree of influence of adjacent flow channel combinations.

[0010] If the impact is high, the unidirectional strongly coupled flow channel is extracted, and the optimized flow direction ratio of the unidirectional strongly coupled flow channel is deduced based on the flow field characteristic data of the unidirectional strongly coupled flow channel. Based on the optimized flow direction ratio of the unidirectional strongly coupled flow channel, the control strategy is executed.

[0011] A control system for a zoned reheat condenser, the system comprising:

[0012] Flow channel identification module: Each flow channel of the partitioned reheat condenser is evenly divided into multiple regions. By collecting temperature and pressure data of each region, the heat transfer intensity of the region is inferred, and the high turbulence region and low pressure drop region in each flow channel are identified.

[0013] Optimization Requirements Assessment Module: Based on the high turbulence zone and low pressure drop zone within each flow channel, the optimization requirements of the flow channel are assessed through the matching and turbulence uniformity of the high turbulence zone and low pressure drop zone.

[0014] Adjacent flow channel analysis module: Extract high-optimization-demand flow channels and integrate them into the same category to obtain high-optimization-demand flow channel groups. Then, extract adjacent flow channel combinations in the high-optimization-demand flow channel groups and analyze the degree of influence of adjacent flow channel combinations.

[0015] Parameter back-calculation and control execution module: If the impact is high, the unidirectional strongly coupled flow channel is extracted, and the optimized flow direction ratio of the unidirectional strongly coupled flow channel is back-calculated based on the flow field characteristic data of the unidirectional strongly coupled flow channel. Based on the optimized flow direction ratio of the unidirectional strongly coupled flow channel, the control strategy is executed.

[0016] The beneficial effects of this invention are as follows:

[0017] This embodiment first identifies anomalous regions such as high turbulence zones and low pressure drop zones within the flow channel, providing a clear spatial coordinate and categorized basis for subsequent optimization. Based on the anomalous region data from the first step, the optimization needs of the flow channel are assessed through a dual-dimensional analysis of matching and uniformity. Flow channels with high optimization needs are selected, allowing optimization resources to focus on key issues and reducing blind adjustments. Flow channels with high demand are then clustered according to their defect causes. The consistency coefficient and spatial correlation of adjacent flow channel combinations are further analyzed to determine combinations with high impact. The problem extends from single flow channel issues to the coupling relationship between flow channels, clarifying mutual interference. Finally, unidirectional strongly coupled flow channels are extracted from high-impact combinations to reverse-engineer the flow split ratio and implement differentiated control. This progressive approach enables optimization measures to address local overheating and flow short-circuiting caused by non-uniform flow, achieving the goals of improving condenser efficiency and reducing risks. Attached Figure Description

[0018] The invention will now be further described with reference to the accompanying drawings.

[0019] Figure 1 This is a flowchart of the steps of a control method for a partitioned reheat condenser according to the present invention;

[0020] Figure 2 This is a control system architecture diagram of a partitioned reheat condenser according to the present invention. Detailed Implementation

[0021] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0022] Example 1

[0023] Please see Figure 1 As shown in the figure, a control method for a zoned reheat condenser according to an embodiment of the present invention includes the following steps:

[0024] Step 1: Divide each flow channel of the partitioned reheat condenser into multiple regions. By collecting temperature and pressure data of each region, infer the heat transfer intensity of the region and identify the high turbulence region and low pressure drop region in each flow channel.

[0025] In some embodiments, based on any one flow channel in the partitioned reheat condenser, the flow channel is uniformly divided into multiple sub-regions using a three-dimensional orthogonal partitioning method with the flow channel axis as the reference.

[0026] Specifically, with the center of the flow channel inlet as the origin, the fluid flow direction is the X-axis, the flow channel width direction is the Y-axis, and the plate spacing direction is the Z-axis;

[0027] For the X-axis partition: Divide according to half of the ripple period to ensure that each partition covers at least one ripple inflection node (flow change point).

[0028] For Y-axis partitioning: Based on the distribution pattern of the plate corrugations, the partitions are divided according to the width of each complete corrugation unit to ensure that each partition contains a complete corrugation undulation structure;

[0029] For Z-axis partitioning: Divide the channel into 3 regions evenly according to the channel height H;

[0030] Each region is named using the format "channel number - X-axis number - Y-axis number - Z-axis number", and the coordinate range of each region is obtained.

[0031] For example, a region named "1-3-2-1" represents flow channel 1, zone 3 in the X direction, zone 2 in the Y direction, and zone 1 in the Z direction.

[0032] A preset data collection period is defined, which is set by those skilled in the art based on the data collection frequency.

[0033] For any data collection period, calculate the average value of the temperature data and the average value of the pressure data within the data collection period, and use them as the average local static pressure and the average wall temperature, respectively.

[0034] Based on the type of refrigerant (such as R32, R134a), the corresponding saturation temperature can be found by looking up the average local static pressure. Those skilled in the art can obtain this information through the refrigerant temperature-pressure fitting formula or the refrigerant property table.

[0035] The difference between the saturation temperature and the average wall temperature is calculated as the subcooling of the region;

[0036] For all two adjacent regions along the X-axis, calculate the average local static pressure difference between the two regions and take the absolute value (i.e., the absolute value of the difference between the region with the larger index and the region with the smaller index) as the pressure gradient;

[0037] Calculate the average subcooling and average pressure gradient for all regions;

[0038] For any given region, if the region’s supercooling is greater than 1.5 times the average supercooling and the pressure gradient is greater than 1.1 times the average pressure gradient, it is determined to be a high-turbulence region.

[0039] If the subcooling of a region is less than 0.8 times the average subcooling and the pressure gradient is less than 0.6 times the average pressure gradient, it is determined to be a low pressure drop region.

[0040] The remaining area of ​​the flow channel is classified as a normal area.

[0041] Step 2: Based on the high turbulence region and low pressure drop region within each flow channel, the optimization requirements of the flow channel are evaluated through the matching and turbulence uniformity of the high turbulence region and low pressure drop region.

[0042] In some embodiments, the high turbulence region and low pressure drop region of each flow channel are obtained, and the average value of the undercooling in the high turbulence region and the average value of the pressure gradient in the low pressure drop region are calculated respectively.

[0043] The total number of highly turbulent regions is counted, and the proportion of the total number of highly turbulent regions to the total number of regions is calculated as the proportion of highly turbulent regions.

[0044] The total number of low-pressure drop areas is counted, and the proportion of the total number of low-pressure drop areas to the total number of areas is calculated as the proportion of low-pressure drop areas.

[0045] The maximum value between the total proportion of the high turbulence region and the total proportion of the low pressure drop region is extracted as the spatial matching coefficient;

[0046] The heat transfer intensity of the high turbulence region is obtained by comparing the average subcooling of the high turbulence region with the average subcooling of all regions. The drag intensity of the low pressure drop region is obtained by comparing the average pressure gradient of the low pressure drop region with the average pressure gradient of all regions.

[0047] The ratio of the heat transfer intensity in the high turbulence region to the drag intensity in the low pressure drop region is used to obtain the parameter matching coefficient.

[0048] If the parameter matching coefficient is within the parameter matching standard range and the spatial matching coefficient is greater than the spatial matching standard value, then the matching level is judged to be excellent.

[0049] If the parameter matching coefficient is not within the parameter matching standard range and the spatial matching coefficient is less than or equal to the spatial matching standard value, the matching level is judged as poor.

[0050] The parameter matching standard range is determined by those skilled in the art based on the goal of achieving heat exchange-resistance balance under condenser design conditions. The parameter matching coefficients of similar high-efficiency flow channels are statistically analyzed, and a 90% confidence interval is taken as the standard range to ensure that heat exchange and resistance characteristics are complementary.

[0051] The standard value for spatial matching is determined by experts in the field based on the maximum percentage of high / low pressure drop zones in a normal flow channel without local overheating or short circuits, combined with the characteristics of the corrugated structure and engineering experience, and is set at 60%.

[0052] It needs to be explained that the matching is judged from the spatial and parameter dimensions. Specifically, it is done by quantifying the balance of regional distribution and the complementarity of characteristic functions to provide a basis for the assessment of flow channel optimization needs. The spatial matching coefficient directly reflects the balance of the spatial proportion of the two types of regions. If the spatial matching coefficient is much greater than the standard value, it indicates that a certain type of region is over-concentrated. The parameter matching coefficient focuses on the functional complementarity of the two types of regions. If the ratio is much greater than the standard range (heat transfer intensity is much higher than resistance intensity), it indicates that the strong heat transfer advantage of the high turbulence region has not corresponded to the resistance compensation of the low pressure drop region. If the ratio is much less than the standard range (resistance intensity is much higher than heat transfer intensity), it indicates that the low resistance of the low pressure drop region has not brought about an effective improvement in heat transfer.

[0053] Calculate the coefficient of variation of subcooling and pressure gradient for all regions, and calculate the arithmetic mean of the coefficient of variation of subcooling and pressure gradient for each region as the uniformity coefficient.

[0054] The uniformity coefficient can comprehensively reflect the overall dispersion of heat transfer intensity (subcooling) and flow resistance (pressure gradient);

[0055] If the uniformity coefficient is less than or equal to the uniformity coefficient threshold, the uniformity level is judged to be excellent.

[0056] If the uniformity coefficient is greater than the uniformity coefficient threshold, the uniformity level is judged as poor.

[0057] The uniformity coefficient threshold is determined by a person skilled in the art using a sample of normally operating condensers without local overheating or short circuits as samples, and the 95th percentile is taken as the uniformity coefficient threshold.

[0058] If the matching level is determined to be poor and the uniformity level is determined to be poor, then it is marked as a high-flow channel with optimization requirements;

[0059] If the matching level is determined to be excellent and the uniformity level is determined to be excellent, then it is marked as a low-flow channel with optimization requirements.

[0060] If the matching level is judged as poor and the uniformity level is judged as good, or the matching level is judged as good and the uniformity level is judged as poor, then it is marked as a medium flow channel with optimization requirements.

[0061] It should be explained that flow channels with all grades being excellent are classified as low-demand flow channels, flow channels with all grades being poor are classified as high-demand flow channels, and all others are classified as medium-demand flow channels. This is because the degree of flow channel performance defects is determined by the two dimensions of matching and uniformity working together, which allows for precise classification and optimization of demand and processing priority.

[0062] Step 3: Extract high-demand flow channels for optimization and integrate them into the same category to obtain high-demand flow channel groups. Then, extract adjacent flow channel combinations in the high-demand flow channel groups and analyze the degree of influence of adjacent flow channel combinations.

[0063] In some embodiments, flow channels marked as having high optimization requirements are extracted, and cluster analysis is performed using the K-means clustering algorithm based on the consistency of defect causes.

[0064] Obtain the spatial matching coefficient, parameter matching coefficient, coefficient of variation of regional subcooling, and coefficient of variation of pressure gradient corresponding to the flow channel with high optimization requirements, and use maximum-minimum standardization to map the values ​​to the range [0,1].

[0065] The optimal K value is automatically calculated using the elbow rule. A curve is plotted with the sum of squared errors within the cluster (SSE) as the ordinate and the K value as the abscissa. The K value corresponding to the inflection point of the curve (the K value corresponding to the inflection point where the curve changes from a steep drop to a gentle drop) is the optimal number of clusters.

[0066] The clustering process based on the optimal K value includes:

[0067] K feature vectors of flow channels are randomly selected from the standardized dataset as initial centers;

[0068] Calculate the Euclidean distance from each flow channel to the two initial centers and assign it to the cluster with the smallest Euclidean distance;

[0069] Calculate the average value of the normalized features of all channels within each cluster, and use it as the new cluster center;

[0070] Perform iterative processing until the cluster center positions are stable (the difference between the centers of two iterations is <0.01) or the maximum number of iterations is reached (e.g., 100 times).

[0071] Based on the final clustering results, channels belonging to the same cluster are grouped into the same category of channels and used as the channel group with high optimization requirements.

[0072] For any high-flow-channel group with optimization requirements, extract the physically adjacent flow channels and use them as adjacent flow-channel combinations.

[0073] For any pair of adjacent flow channels, they are respectively denoted as the first flow channel and the second flow channel;

[0074] The average pressure gradient of all regions in the first flow channel is subtracted from the average pressure gradient of all regions in the second flow channel. The absolute value of the difference is then compared with the average pressure gradient of all high-optimization flow channels to obtain the consistency coefficient.

[0075] It should be explained that the consistency coefficient reflects whether the flow resistance characteristics of the two flow channels are highly correlated. The smaller the consistency coefficient, the smaller the difference in flow resistance characteristics between the first flow channel and the second flow channel, the closer the average pressure gradient, and the more significant the mutual influence. The larger the consistency coefficient, the larger the difference in flow resistance characteristics between the first flow channel and the second flow channel.

[0076] The high turbulence region and low pressure drop region corresponding to the first and second flow channels are both marked as abnormal areas;

[0077] Identify whether there is volume overlap between the abnormal regions of the first and second flow channels. If there is overlap, define the spatial correlation degree as 1.

[0078] If there is no overlap, calculate the shortest spatial distance between the abnormal regions of the first and second flow channels (i.e., the minimum straight-line distance between the edges of the abnormal regions in three-dimensional space).

[0079] The period length of a single corrugated unit in the corrugated structure within the flow channel is taken as the characteristic dimension of the flow channel, and twice the characteristic dimension of the flow channel is taken as the critical influence distance.

[0080] The ratio of the shortest spatial distance to the critical influence distance is calculated to obtain the relative distance ratio. The relative distance ratio is then converted into spatial correlation degree, which is obtained by subtracting the relative distance ratio from 1.

[0081] It should be explained that spatial correlation reflects the potential and intensity of mutual interference between anomalous regions (high turbulence region, low pressure drop region) of adjacent flow channels due to their spatial location. It is the influence of physical proximity on defect transmission based on the structural characteristics of the flow channels. The greater the spatial correlation, the more likely the anomalous regions of the two flow channels are within each other's effective interference range, and the higher the possibility of mutual aggravation through spatial proximity. The smaller the spatial correlation, the more likely the anomalous regions are far apart or beyond the critical influence range, and the weaker the potential for mutual interference at the spatial level.

[0082] The influence coefficient is obtained by averaging the spatial correlation degree and the consistency coefficient.

[0083] It should be noted that if the consistency coefficient is zero, it means that the flow resistance characteristics of the two flow channels are completely consistent and the mutual influence is the most significant. Therefore, it is directly determined that the influence between the two flow channels is high.

[0084] If the influence coefficient is greater than the influence coefficient threshold, it indicates that the influence of the adjacent flow channel combination is high;

[0085] If the influence coefficient is less than or equal to the influence coefficient threshold, it indicates that the influence of the adjacent flow channel combination is low.

[0086] Step 4: If the impact is high, extract the unidirectional strongly coupled flow channel, and back-calculate the optimized flow ratio of the unidirectional strongly coupled flow channel based on the flow field characteristic data of the unidirectional strongly coupled flow channel. Based on the optimized flow ratio of the unidirectional strongly coupled flow channel, execute the control strategy.

[0087] In some embodiments, adjacent flow channel combinations with high influence are obtained, and any adjacent flow channel combination with high influence is marked as adjacent influential flow channel A and adjacent influential flow channel B, respectively.

[0088] Calculate the volume percentage V1 of the abnormal region in adjacent influencing channel A and the volume percentage V2 of the abnormal region in adjacent influencing channel B, and identify the maximum value of V1 and V2.

[0089] If V1 is large, calculate the difference between V1 and V2. If the difference is greater than 10%, then the adjacent influencing channel A has spatial dominance.

[0090] If V2 is large, calculate the difference between V2 and V1. If the difference is greater than 10%, then the adjacent influencing channel B has spatial dominance.

[0091] Otherwise, it lacks unidirectional dominance;

[0092] The directionality of conduction is verified by combining the flow characteristics of the fluid along the X-axis. If the adjacent influencing channel A has spatial dominance and the initial X-axis coordinate value of the adjacent influencing channel A is less than or equal to the initial X-axis coordinate value of the adjacent influencing channel B, then the adjacent influencing channel A is determined to be a unidirectional strongly coupled channel.

[0093] If the adjacent influencing channel B has spatial dominance, and the initial X-axis coordinate value of the adjacent influencing channel B is less than or equal to the initial X-axis coordinate value of the adjacent influencing channel A, then the adjacent influencing channel B is determined to be a unidirectional strongly coupled channel.

[0094] If a unidirectional strongly coupled flow channel is found in an adjacent flow channel combination, then the other one is the receiver flow channel;

[0095] The volume ratio difference between the abnormal regions of the unidirectional strongly coupled flow channel and the receptor flow channel is obtained as the volume ratio difference.

[0096] The ratio of the average pressure gradient in the abnormal region of the unidirectional strongly coupled flow channel to the average pressure gradient in the abnormal region of the receiver flow channel is calculated as the pressure gradient ratio.

[0097] The optimized split ratio is obtained by multiplying the volume ratio difference with the adjustment coefficient.

[0098] It should be noted that the adjustment coefficient is set by those skilled in the art based on historical data. If the pressure gradient ratio is less than or equal to 0.3, the adjustment coefficient is 0.8; if the pressure gradient ratio is greater than 0.3, the adjustment coefficient is 0.6.

[0099] Based on calculations, the flow split ratio of the unidirectional strongly coupled flow channel is optimized, and control strategies are implemented, including but not limited to:

[0100] Differentiated flow diversion control is implemented based on the type of unidirectional strongly coupled flow channel: For the abnormal region type (high turbulence region / low pressure drop region) of each source flow channel, the operation is based on the regional characteristics in step one. If it is a low pressure drop region (flow short circuit), the "main channel throttling in abnormal region + auxiliary channel diversion in normal region" mode is adopted. The number of closed branch channels = optimized diversion ratio × total number of branches, and the opening of the auxiliary channel = diversion ratio × 100%; If it is a high turbulence region (local overheating), the main channel cross section is reduced along the X-axis according to the length ratio of the abnormal region. The reduction range is distributed to the diversion ratio in each region. When multiple source flow channels are executed, the flow channels in the same group are adjusted synchronously. Different groups are sorted according to the influence degree coefficient in step three (the higher the coefficient, the higher the priority), and the initial flow parameters of the corresponding receiver flow channel are kept unchanged to avoid interfering with the receiver flow field.

[0101] This embodiment uses a three-dimensional orthogonal partitioning method to accurately divide the flow channel region, and combines the indicators of supercooling and pressure gradient to identify the high turbulence region and low pressure drop region. This optimizes the problem of fuzzy positioning and inaccurate type judgment of the flow channel defect region, thereby providing a basis with clear spatial coordinates and clear defect attributes for subsequent optimization, and reducing the misalignment of optimization direction caused by blind adjustment.

[0102] This embodiment assesses the flow channel optimization requirements through matching and uniformity, and then uses K-means clustering to group high-demand flow channels according to the cause of defects. This optimizes some large condenser flow channels with a large number of defects and complex defects, which leads to resource waste due to indiscriminate optimization. This achieves precise allocation of optimization resources, focusing only on flow channels with poor uniformity. Furthermore, by grouping and analyzing the same category, optimization efficiency is improved, and energy consumption and time loss caused by ineffective operations are reduced.

[0103] This embodiment optimizes the problems of local overheating, flow short circuit, and coupling interference between adjacent flow channels caused by non-uniform flow by determining the unidirectional strongly coupled flow channel, back-calculating and optimizing the flow split ratio, and then performing differentiated control according to the abnormal region type. This reduces the heat transfer dead zone, balances the heat transfer and resistance characteristics of the flow channel, reduces pumping energy consumption, blocks defect diffusion, and reduces the risk of material fatigue and seal failure.

[0104] This embodiment first identifies anomalous regions such as high turbulence zones and low pressure drop zones within the flow channel, providing a clear spatial coordinate and categorized basis for subsequent optimization. Based on the anomalous region data from the first step, the optimization needs of the flow channel are assessed through a dual-dimensional analysis of matching and uniformity. Flow channels with high optimization needs are selected, allowing optimization resources to focus on key issues and reducing blind adjustments. Flow channels with high demand are then clustered according to their defect causes. The consistency coefficient and spatial correlation of adjacent flow channel combinations are further analyzed to determine combinations with high impact. The problem extends from single flow channel issues to the coupling relationship between flow channels, clarifying mutual interference. Finally, unidirectional strongly coupled flow channels are extracted from high-impact combinations to reverse-engineer the flow split ratio and implement differentiated control. This progressive approach enables optimization measures to address local overheating and flow short-circuiting caused by non-uniform flow, achieving the goals of improving condenser efficiency and reducing risks.

[0105] Example 2

[0106] Based on the same inventive concept as the control method for a partitioned reheat condenser in the foregoing embodiments, such as Figure 2 As shown, this application provides a control system for a zoned reheat condenser, wherein the system specifically includes:

[0107] Flow channel identification module: Each flow channel of the partitioned reheat condenser is evenly divided into multiple regions. By collecting temperature and pressure data of each region, the heat transfer intensity of the region is inferred, and the high turbulence region and low pressure drop region in each flow channel are identified.

[0108] Optimization Requirements Assessment Module: Based on the high turbulence zone and low pressure drop zone within each flow channel, the optimization requirements of the flow channel are assessed through the matching and turbulence uniformity of the high turbulence zone and low pressure drop zone.

[0109] Adjacent flow channel analysis module: Extract high-optimization-demand flow channels and integrate them into the same category to obtain high-optimization-demand flow channel groups. Then, extract adjacent flow channel combinations in the high-optimization-demand flow channel groups and analyze the degree of influence of adjacent flow channel combinations.

[0110] Parameter back-calculation and control execution module: If the impact is high, the unidirectional strongly coupled flow channel is extracted, and the optimized flow direction ratio of the unidirectional strongly coupled flow channel is back-calculated based on the flow field characteristic data of the unidirectional strongly coupled flow channel. Based on the optimized flow direction ratio of the unidirectional strongly coupled flow channel, the control strategy is executed.

[0111] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A control method for a zoned reheat condenser, characterized in that: include: Each flow channel of the plate condenser containing corrugated plates is evenly divided into multiple regions. By collecting temperature and pressure data of each region, the heat transfer intensity of the region is inferred, and the high turbulence region and low pressure drop region in each flow channel are identified. Based on any flow channel in a plate condenser containing corrugated plates, the flow channel is uniformly divided into multiple sub-regions using a three-dimensional orthogonal partitioning method, with the flow channel axis as the reference. Specifically, with the center of the flow channel inlet as the origin, the fluid flow direction is the X-axis, the flow channel width direction is the Y-axis, and the plate spacing direction is the Z-axis. For the X-axis partition: it is divided according to half of the corrugation period, ensuring that each partition covers at least one corrugation turning node. For the Y-axis partition: it is divided according to the corrugation distribution pattern of the plates, with the width of each complete corrugated unit as the reference, ensuring that each partition contains a complete corrugated undulation structure. For the Z-axis partition: it is uniformly divided into 3 regions according to the flow channel height H. Based on the high turbulence region and low pressure drop region within each flow channel, the optimization requirements of the flow channel are evaluated by assessing the matching and turbulence uniformity between the high turbulence region and the low pressure drop region. Extract high-demand flow channels and integrate them into the same category to obtain high-demand flow channel groups. Then, extract adjacent flow channel combinations in the high-demand flow channel groups and analyze the degree of influence of adjacent flow channel combinations. If the impact is high, the unidirectional strongly coupled flow channel is extracted, and the optimized flow direction ratio of the unidirectional strongly coupled flow channel is deduced based on the flow field characteristic data of the unidirectional strongly coupled flow channel. Based on the optimized flow direction ratio of the unidirectional strongly coupled flow channel, the control strategy is executed.

2. The control method for a zoned reheat condenser according to claim 1, characterized in that: The process for identifying the high turbulence region and the low pressure drop region is as follows: For any preset data collection period, calculate the average value of the temperature data and the average value of the pressure data within the data collection period, and use them as the average local static pressure and the average wall temperature, respectively. The saturation temperature corresponding to the average local static pressure is found, and the difference between the saturation temperature and the average wall temperature is calculated as the subcooling of the region. For all two adjacent regions, calculate the average local static pressure difference between the two regions and take the absolute value as the pressure gradient; Calculate the average subcooling and average pressure gradient for all regions; If the subcooling of a region is greater than 1.5 times the average subcooling and the pressure gradient is greater than 1.1 times the average pressure gradient, it is determined to be a high-turbulence region. If the subcooling of a region is less than 0.8 times the average subcooling and the pressure gradient is less than 0.6 times the average pressure gradient, it is determined to be a low pressure drop region.

3. The control method for a zoned reheat condenser according to claim 1, characterized in that: The process of evaluating the optimization requirements for the flow channel is as follows: The high turbulence region and low pressure drop region of each flow channel are analyzed to obtain the matching level and uniformity level; If both the matching level and the uniformity level are judged to be poor, then it is marked as a high-flow channel requiring optimization.

4. The control method for a zoned reheat condenser according to claim 3, characterized in that: The analysis process for the matching level is as follows: Calculate the proportion of the total number of high turbulence regions to the total number of regions and the proportion of the total number of low pressure drop regions to the total number of regions, and extract the maximum value as the spatial matching coefficient; The heat transfer intensity in the high turbulence region is obtained by calculating the ratio of the average subcooling in the high turbulence region to the average subcooling in all regions. The drag intensity in the low pressure drop region is obtained by calculating the ratio of the average pressure gradient in the low pressure drop region to the average pressure gradient in all regions. The ratio of the heat transfer intensity in the high turbulence region to the drag intensity in the low pressure drop region is used to obtain the parameter matching coefficient. If the parameter matching coefficient is not within the parameter matching standard range and the spatial matching coefficient is less than or equal to the spatial matching standard value, the matching level is judged as poor.

5. The control method for a zoned reheat condenser according to claim 3, characterized in that: The analysis process for the uniformity level is as follows: Calculate the coefficient of variation of subcooling and pressure gradient for all regions, and calculate the arithmetic mean of the coefficient of variation of subcooling and pressure gradient for each region as the uniformity coefficient. If the uniformity coefficient is greater than the uniformity coefficient threshold, the uniformity level is judged as poor.

6. The control method for a zoned reheat condenser according to claim 1, characterized in that: The process for obtaining the optimized high-flow channel group is as follows: Obtain the spatial matching coefficient, parameter matching coefficient, coefficient of variation of regional subcooling, and coefficient of variation of pressure gradient for flow channels with high optimization requirements, and perform cluster analysis using the K-means clustering algorithm; Based on the final clustering results, channels belonging to the same cluster are grouped into the same category of channels and designated as high-demand channel groups for optimization.

7. The control method for a zoned reheat condenser according to claim 1, characterized in that: The process of analyzing the degree of influence of adjacent flow channel combinations is as follows: Adjacent flow channel combinations are respectively referred to as the first flow channel and the second flow channel; The average pressure gradient of all regions in the first flow channel is subtracted from the average pressure gradient of all regions in the second flow channel. The absolute value of the difference is then compared with the average pressure gradient of all high-optimization flow channels to obtain the consistency coefficient. The high turbulence region and low pressure drop region corresponding to the first and second flow channels are both marked as abnormal areas; Identify whether there is volume overlap between the abnormal regions of the first and second flow channels. If there is overlap, define the spatial correlation degree as 1. If there is no overlap, calculate the shortest spatial distance between the abnormal regions of the first and second flow channels; The ratio of the shortest spatial distance to the critical influence distance is calculated to obtain the relative distance ratio, and the relative distance ratio is converted into spatial correlation degree. The influence coefficient is obtained by averaging the spatial correlation degree and the consistency coefficient. If the influence coefficient is greater than the influence coefficient threshold, it indicates that the influence of the adjacent flow channel combination is high.

8. The control method for a zoned reheat condenser according to claim 1, characterized in that: The extraction process of the unidirectional strongly coupled flow channel is as follows: For any adjacent flow channel combination with a high degree of influence, they are respectively labeled as adjacent influential flow channel A and adjacent influential flow channel B; Calculate the volume percentage V1 of the abnormal region in adjacent influencing channel A and the volume percentage V2 of the abnormal region in adjacent influencing channel B, and identify the maximum value of V1 and V2. If V1 is large, calculate the difference between V1 and V2. If the difference is greater than 10%, then the adjacent influencing channel A has spatial dominance. If V2 is large, calculate the difference between V2 and V1. If the difference is greater than 10%, then the adjacent influencing channel B has spatial dominance. If the adjacent influencing channel A has spatial dominance, and the initial X-axis coordinate value of the adjacent influencing channel A is less than or equal to the initial X-axis coordinate value of the adjacent influencing channel B, then the adjacent influencing channel A is determined to be a unidirectional strongly coupled channel. If the adjacent influencing channel B has spatial dominance, and the initial X-axis coordinate value of the adjacent influencing channel B is less than or equal to the initial X-axis coordinate value of the adjacent influencing channel A, then the adjacent influencing channel B is determined to be a unidirectional strongly coupled channel.

9. The control method for a zoned reheat condenser according to claim 1, characterized in that: The process of obtaining the optimized flow ratio is as follows: If a unidirectional strongly coupled flow channel is found in an adjacent flow channel combination, then the other one is the receiver flow channel; The volume ratio difference between the abnormal regions of the unidirectional strongly coupled flow channel and the receptor flow channel is obtained as the volume ratio difference. The ratio of the average pressure gradient in the abnormal region of the unidirectional strongly coupled flow channel to the average pressure gradient in the abnormal region of the receiver flow channel is calculated as the pressure gradient ratio. The optimized split ratio is obtained by multiplying the volume ratio difference with the adjustment coefficient.

10. A control system for a zoned reheat condenser, characterized in that, The system is used to perform the method according to any one of claims 1-9, the system comprising: Flow channel identification module: Each flow channel of the partitioned reheat condenser is evenly divided into multiple regions. By collecting temperature and pressure data of each region, the heat transfer intensity of the region is inferred, and the high turbulence region and low pressure drop region in each flow channel are identified. Optimization Requirements Assessment Module: Based on the high turbulence zone and low pressure drop zone within each flow channel, the optimization requirements of the flow channel are assessed through the matching and turbulence uniformity of the high turbulence zone and low pressure drop zone. Adjacent flow channel analysis module: Extract high-optimization-demand flow channels and integrate them into the same category to obtain high-optimization-demand flow channel groups. Then, extract adjacent flow channel combinations in the high-optimization-demand flow channel groups and analyze the degree of influence of adjacent flow channel combinations. Parameter back-calculation and control execution module: If the impact is high, the unidirectional strongly coupled flow channel is extracted, and the optimized flow direction ratio of the unidirectional strongly coupled flow channel is back-calculated based on the flow field characteristic data of the unidirectional strongly coupled flow channel. Based on the optimized flow direction ratio of the unidirectional strongly coupled flow channel, the control strategy is executed.

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