Optimization method, system, and medium for an oxidation ditch based on computational fluid dynamics simulation

Abstract

The application discloses an oxidation ditch optimization method and system based on computational fluid dynamics simulation and a medium, mainly relates to the technical field of oxidation ditch optimization, and is used to solve the problems that the existing process of finding solutions to poor backflow, high energy consumption, sludge deposition and adjustment of the oxidation ditch running state highly depends on artificial experience, and needs repeated tests and verification, resulting in long adjustment period and low efficiency. The method comprises the following steps: establishing an oxidation ditch three-dimensional model; obtaining distribution data, a velocity field and sludge concentration distribution data; presetting operation parameters of a stirrer and a flow pusher returned by an expert terminal; using the oxidation ditch three-dimensional model, simulating angles and rotating speeds of the flow pusher and the stirrer under different sewage and mixed liquid and backflow sludge flow data to meet preset flow field flow state, and saving the angles and the rotating speeds in a simulation flow field flow state database; collecting actual water flow data, obtaining corresponding angle and rotating speed data of the flow pusher and the stirrer from the simulation flow field flow state database, and automatically adjusting the angles and the rotating speeds.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of wastewater treatment, and particularly to an oxidation ditch optimization method and system based on computational fluid dynamics simulation and a medium. BACKGROUND

[0002] An oxidation ditch is an activated sludge treatment process, the core of which is to make sewage and activated sludge mixed liquid flow in a closed ditch. The oxidation ditch process combines the characteristics of plug flow and complete mixing, effectively overcomes the short flow phenomenon, improves the buffering capacity of the system, has strong impact load capacity, and also shows good removal effect on refractory organic matter. However, in practical application, the oxidation ditch process still faces some technical problems, such as poor internal reflux, high energy consumption, sludge deposition, etc. These problems lead to low treatment efficiency of the oxidation ditch process and increase its operating cost.

[0003] In order to solve the above problems, the existing technology mainly simulates the state of water and sludge in the current oxidation ditch (whether the reflux is not smooth, the energy consumption is high, the sludge deposition, etc.) through the oxidation ditch sludge simulation model (for example, Realizable k-ε turbulence model and Eulerian multiphase flow model). In the specific implementation process, the specific operation data of the oxidation ditch (for example, the angle and speed of the push flow device and the stirrer) in the oxidation ditch sludge simulation model need to be adjusted manually. By continuously adjusting the operation data of the oxidation ditch, the best data that can solve the problems of poor reflux, high energy consumption, and sludge deposition are obtained. Specifically, although the best oxidation ditch data that can solve the problems of poor reflux, high energy consumption, and sludge deposition can be obtained by continuous adjustment, this process highly depends on manual experience and needs repeated testing and verification, resulting in long adjustment period and low efficiency. SUMMARY

[0004] In view of the above deficiencies of the prior art, the present application provides an oxidation ditch optimization method and system based on computational fluid dynamics simulation and a medium to solve the problem that the process of finding oxidation ditch data that solves the problems of poor reflux, high energy consumption, and sludge deposition highly depends on manual experience and needs repeated testing and verification, resulting in long adjustment period and low efficiency.

[0005] In the first aspect, the present application provides an oxidation ditch optimization method based on computational fluid dynamics simulation, which comprises:

[0006] obtain the grid division data and the boundary condition of the three-dimensional model of the oxidation ditch by using the CFD software ANSYS fluent, update the three-dimensional model of the oxidation ditch, wherein the boundary condition comprises simulation operation parameters of the water inlet, the water weir and the reflux port in the three-dimensional model, set the initial mixed liquid suspended solid concentration of the water inlet and the reflux corresponding to the turbulent condition, and then obtain the distribution data, the velocity field and the sludge concentration distribution data of the sludge in the three-dimensional model of the oxidation ditch by using the Realizable k-ε turbulent model and the Eulerian multiphase flow model; send the distribution data, the velocity field and the sludge concentration distribution data of the current sludge in the three-dimensional model of the oxidation ditch to a preset expert terminal, and obtain the returned operation parameters of the agitator and the flow pusher; wherein the operation parameters at least comprise the impeller diameter, the angle, the rotating speed and the installation position of the agitator and the flow pusher; simulate the angle and the rotating speed of the flow pusher and the agitator that meet the preset flow field flow state under different water flow data by using the three-dimensional model of the oxidation ditch, and save them in a simulation flow field flow state database; collect the water flow data detected by a front flow meter in the actual oxidation ditch corresponding to the three-dimensional model of the oxidation ditch, obtain the corresponding angle and rotating speed of the flow pusher and the agitator from the simulation flow field flow state database according to the actual water flow data, and return them to an oxidation ditch operation equipment control terminal.

[0007] In an implementation manner of the present application, the grid division data and the boundary condition of the three-dimensional model of the oxidation ditch are obtained by using the CFD software ANSYS fluent, the three-dimensional model of the oxidation ditch is updated, and specifically includes:

[0008] the three-dimensional model of the oxidation ditch is imported into the ANSYS fluent software;

[0009] the grid division data of the three-dimensional model of the oxidation ditch is read based on a preset reading address, and the grid division data is configured into the current ANSYS fluent software; wherein the grid division data of the three-dimensional model of the oxidation ditch at least comprises the grid type, the grid size, the grid density and the grid distribution of each region in the three-dimensional model;

[0010] the boundary condition is read based on a preset reading address, and the boundary condition is configured into the current ANSYS fluent software.

[0011] In an implementation manner of the present application, the distribution data, the velocity field and the sludge concentration distribution data of the current sludge in the three-dimensional model of the oxidation ditch are sent to a preset expert terminal, and the returned operation parameters of the agitator and the flow pusher are obtained, and specifically includes:

[0012] S1, send the distribution data of the current sludge, the velocity field and the sludge concentration distribution data of the sludge in the oxidation ditch three-dimensional model to all preset expert terminals;

[0013] S2, broadcast the operation parameters of the first returned mixer and pusher to all preset expert terminals;

[0014] S3, obtain the operation parameter evaluation result; when more than a preset proportion of the operation parameter evaluation result is reasonable, determine that the operation parameters of the current mixer and pusher are the final operation parameters of the mixer and pusher;

[0015] S4, when not more than a preset proportion of the operation parameter evaluation result is reasonable, obtain the operation parameters uploaded by the expert terminal with an unreasonable operation parameter evaluation result;

[0016] S5, based on the preset weight of the unreasonable expert terminal, broadcast the operation parameters of the expert terminal with the maximum preset weight to all preset expert terminals; obtain the operation parameter evaluation result;

[0017] S6, cycle S3-S5 until more than a preset proportion of the operation parameter evaluation result is reasonable, and determine that the operation parameters of the current mixer and pusher are the final operation parameters of the mixer and pusher;

[0018] S7, increase the preset weight of the uploading expert terminal corresponding to the final operation parameters of the mixer and pusher by a preset first weight value; increase the preset weight of the expert terminal returning the final operation parameters of the mixer and pusher as reasonable by a preset second weight value; wherein, the preset first weight value> the preset second weight value.

[0019] In an implementation manner of the present application, the initial mixed liquid suspended solid concentration of the water inlet and the backflow corresponding to the turbulent condition is set, and then the distribution data of the sludge in the oxidation ditch three-dimensional model, the velocity field and the sludge concentration distribution data are obtained by using the Realizable k-ε turbulent model and the Eulerian multiphase flow model, specifically including:

[0020] In the ANSYS fluent, the initial mixed liquid suspended solid concentration of the water inlet and the backflow is set; in the model selection of the ANSYS fluent, the Realizable k-ε turbulent model is selected; at the same time, the Eulerian multiphase flow model is selected to simulate the interaction between the sludge and water; the solver of the ANSYS fluent is started, and simulation calculation is performed according to the set initial mixed liquid suspended solid concentration, the Realizable k-ε turbulent model and the Eulerian multiphase flow model; after the simulation calculation is completed, the distribution data of the sludge in the oxidation ditch three-dimensional model, the velocity field and the sludge concentration distribution data are extracted from the ANSYS fluent.

[0021] In an implementation form of the application, the angles and rotation speeds of the pusher and the agitator that meet the preset flow field flow state under different water flow data are simulated by using the oxidation ditch three-dimensional model, and are saved in the simulated flow field flow state database, and specifically includes:

[0022] In ANSYS fluent, the water flow is set as a variable; for each set water flow value, the angles and rotation speeds of the pusher and the agitator are adjusted, simulation calculation is performed until the angle and rotation speed combination that meets the preset flow field flow state is found; the angle and rotation speed combination of the pusher and the agitator corresponding to each water flow is recorded; the recorded data is arranged into the simulated flow field flow state database; wherein the simulated flow field flow state database includes water flow data, pusher angle, pusher rotation speed, agitator angle, and agitator rotation speed.

[0023] In an implementation form of the application, after returning to the oxidation ditch operation equipment control terminal, the method further includes:

[0024] The adjusted results of the oxidation ditch are obtained after the oxidation ditch operation equipment control terminal returns; wherein the adjustment results at least include whether the sludge concentration is reduced after the preset waiting time period; when the sludge concentration is not reduced after the preset waiting time period, a maintenance task is generated to the preset model maintenance terminal to correct the oxidation ditch three-dimensional model and the corresponding simulated flow field flow state database.

[0025] In a second aspect, the application provides an oxidation ditch optimization system based on computational fluid dynamics simulation, the system includes:

[0026] The establishing module is configured to obtain oxidation ditch structure parameters, and then establish a corresponding oxidation ditch three-dimensional model; wherein the oxidation ditch structure parameters at least include geometric parameters of the mid-parting wall, the flow guide wall, the aeration device, the agitator and the flow pusher; the updating module is configured to obtain grid division data and boundary conditions of the three-dimensional model of the oxidation ditch by using the CFD software ANSYS fluent, and update the oxidation ditch three-dimensional model; wherein the boundary conditions include simulation operation parameters of the water inlet, the water weir and the backflow port in the three-dimensional model; the obtaining module is configured to set the initial mixed liquid suspended solid concentration of the water inlet and the backflow corresponding to the turbulent condition, and then obtain distribution data, a velocity field and sludge concentration distribution data of sludge in the oxidation ditch three-dimensional model by using the Realizable k-ε turbulent model and the Eulerian multiphase flow model; the distribution data, the velocity field and the sludge concentration distribution data of the current sludge in the oxidation ditch three-dimensional model are sent to a preset expert terminal, and the returned operation parameters of the agitator and the flow pusher are obtained; wherein the operation parameters at least include impeller diameter, angle, speed and installation position of the agitator and the flow pusher; the oxidation ditch three-dimensional model is used to simulate the angle and speed of the flow pusher and the agitator that meet a preset flow field flow state under different water flow data, and save in a simulation flow field flow state database; the running module is configured to collect water flow data detected by a front flow meter in the actual oxidation ditch corresponding to the oxidation ditch three-dimensional model, obtain corresponding angles and speeds of the flow pusher and the agitator from the simulation flow field flow state database according to the actual water flow data, and return to an oxidation ditch running equipment control terminal.

[0027] In an implementation manner of the present application, the updating module includes an updating unit configured to import the three-dimensional model of the oxidation ditch into the ANSYS fluent software; read grid division data of the three-dimensional model of the oxidation ditch based on a preset reading address, and configure the grid division data into the current ANSYS fluent software; wherein the grid division data of the three-dimensional model of the oxidation ditch at least includes grid type, grid size, grid density and grid distribution of each region in the three-dimensional model; read the boundary conditions based on a preset reading address, and configure the boundary conditions into the current ANSYS fluent software.

[0028] In an implementation form of the present application, the obtaining module comprises an obtaining unit configured to set an initial mixed liquor suspended solids concentration of the inlet and backflow in ANSYS fluent; in the model selection of ANSYS fluent, a Realizable k-ε turbulence model is selected; at the same time, an Eulerian multiphase flow model is selected to simulate the interaction between sludge and water; the solver of ANSYS fluent is started, and simulation calculation is performed according to the set initial mixed liquor suspended solids concentration, Realizable k-ε turbulence model and Eulerian multiphase flow model; after the simulation calculation is completed, the distribution data of sludge in the three-dimensional model of the oxidation ditch, the velocity field and the sludge concentration distribution data are extracted from ANSYS fluent.

[0029] In a third aspect, the present application provides a non-volatile computer storage medium having computer instructions stored thereon, which, when executed, implement the oxidation ditch optimization method based on computational fluid dynamics simulation according to any one of the above.

[0030] Those skilled in the art can understand that the present application has at least the following beneficial effects:

[0031] By automatically obtaining the oxidation ditch structure parameters and establishing a three-dimensional model, and using the CFD software ANSYS Fluent to perform grid division and boundary condition setting, a three-dimensional model is obtained, wherein the three-dimensional model contains all the structure data of the current oxidation ditch, and can simulate the scene data of the current oxidation ditch according to specific structure parameters.

[0032] The simulated sludge distribution data, velocity field and sludge concentration distribution data are sent to a preset expert terminal, and through analysis of the expert system, the optimal operation parameters of the agitator and the plug flow device can be quickly given. In the implementation process, the impeller diameter, angle (initial), speed (initial) and installation position of the agitator and the plug flow device are obtained by issuing to the expert terminal. After the impeller diameter and installation position of the agitator and the plug flow device are fixed, the three-dimensional model is built.

[0033] Through the built three-dimensional model, the angles and speeds of the plug flow device and the agitator that meet the preset flow field flow state (no backflow, poor flow, high energy consumption, sludge deposition, etc.) under different water flow data are automatically simulated, and a database (simulation flow field flow state database) is established, solving the problem that the existing scheme needs to constantly manually adjust the specific operation data (for example, the angles and speeds of the plug flow device and the agitator) of the oxidation ditch in the oxidation ditch sludge simulation model. According to the simulation flow field flow state database, when the actual water flow changes, the corresponding existing parameters can be obtained from the database according to the actual water flow, and the controller is instructed by the control system to automatically adjust the agitator and the plug flow device.

[0034] By using the simulated flow field and flow state database, we can find the angles and speeds of the flow propeller and agitator that meet the preset flow field and flow state (without problems such as poor backflow, high energy consumption, and sludge deposition) under the water flow data, reducing operating costs and maintenance difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for the description. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 This is a flow chart of an oxidation ditch optimization method based on computational fluid dynamics simulation provided in an embodiment of the present application.

[0037] Figure 2 This is a schematic diagram of a three-dimensional model structure of an oxidation ditch provided in an embodiment of the present application.

[0038] Figure 3 It is a structural schematic diagram of a whole aeration device in a three-dimensional model structure of an oxidation ditch provided in an embodiment of the present application.

[0039] Figure 4 The embodiment of the present application provides a sludge distribution map before optimization.

[0040] Figure 5 An optimized sludge distribution map is provided in an embodiment of the present application.

[0041] Figure 6 This is a schematic diagram of the internal structure of an oxidation ditch optimization system based on computational fluid dynamics simulation provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] Those skilled in the art should understand that the embodiments described below are merely preferred embodiments of the present disclosure and do not imply that the present disclosure can only be implemented through these preferred embodiments. These preferred embodiments are merely intended to explain the technical principles of the present disclosure and are not intended to limit the scope of protection of the present disclosure. Based on the preferred embodiments provided by the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative effort should still fall within the scope of protection of the present disclosure.

[0043] It is also important to note that the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the presence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0044] The technical solutions of the embodiments of the present application are described in detail below with reference to the drawings.

[0045] The embodiments provide an oxidation ditch optimization method based on computational fluid dynamics simulation, as shown in the following figure. Figure 1 The method provided by the embodiments of the present application mainly includes the following steps:

[0046] In step 110, the structure parameters of the oxidation ditch are obtained, and then a corresponding three-dimensional model of the oxidation ditch is established.

[0047] It should be noted that the structure parameters of the oxidation ditch at least include the geometric parameters of the partition wall, the flow guide wall, the aeration device, the agitator and the flow pusher.

[0048] Further, the three-dimensional model of the oxidation ditch according to the present application can be composed of the main body of the oxidation ditch, the sewage inlet, the sewage outlet, the return sludge inlet, the agitator, the flow pusher and the flow guide wall, as shown in the following figure. Figure 2 The agitator is used to mix and push the sludge, and the flow pusher is mainly used for flow pushing.

[0049] In addition, the person skilled in the art can add or delete the data in the above-mentioned structure parameters of the oxidation ditch according to the actual needs. As an example, the non-main structure such as the walkway and the railing is simplified, and the important and complex structure is equivalently simplified, for example, as shown in the following figure. Figure 3 The aeration device according to the present application can equivalently transform the aeration device composed of multiple aeration discs into a plate with the same aeration amount and the same size of bubbles according to the aeration position.

[0050] In step 120, the meshing data and the boundary conditions of the three-dimensional model of the oxidation ditch are obtained by using the CFD software ANSYS fluent, and the three-dimensional model of the oxidation ditch is updated.

[0051] It should be noted that the boundary conditions include the simulation operation parameters of the water inlet, the water weir and the return port in the three-dimensional model.

[0052] This step can be specifically:

[0053] The three-dimensional model of the oxidation ditch is imported into the ANSYS fluent software; based on a preset reading address, grid division data of the three-dimensional model of the oxidation ditch is read, and the grid division data is configured to the current ANSYS fluent software; wherein the grid division data of the three-dimensional model of the oxidation ditch at least includes grid type, grid size, grid density and grid distribution of each region in the three-dimensional model; based on a preset reading address, boundary conditions are read, and the boundary conditions are configured to the current ANSYS fluent software.

[0054] It should be noted that, taking the A / A / O oxidation ditch of a sewage treatment plant with a treatment capacity of 40000m³ / d as an example, the pool size is 110m x 35m x 6m, and the grid division data and boundary conditions can also be specific: mixed grid form is adopted, 3D total grid number is 1.9-2.3 million, and then migrated to other equipment CFD simulation; local encryption is set in the near-wall, aeration area, agitator and flow promoter, and 3 layers of boundary layer grid are set; the inlet is set as a flow rate inlet (v=0.5-0.8 m / s); the outlet weir is set as a pressure outlet; the reflux port is set as a velocity inlet (reflux ratio 40-80%).

[0055] Step 130, setting the initial mixed liquid suspended solid concentration of the influent and reflux corresponding to the turbulent condition, and then using the Realizable k-ε turbulent model and the Eulerian multiphase flow model to obtain the distribution data, velocity field and sludge concentration distribution data of the sludge in the three-dimensional model of the oxidation ditch.

[0056] As an example, this step can be specific to:

[0057] Setting the initial mixed liquid suspended solid concentration of the influent and reflux in ANSYS fluent;

[0058] In the model selection of ANSYS fluent, Realizable k-ε turbulent model is selected;

[0059] At the same time, the Eulerian multiphase flow model is selected to simulate the interaction between sludge and water;

[0060] ‌Starting the solver of ANSYS fluent, and according to the set initial mixed liquid suspended solid concentration, Realizable k-ε turbulent model and Eulerian multiphase flow model, performing simulation calculation;

[0061] After the simulation calculation is completed, the distribution data, velocity field and sludge concentration distribution data of the sludge in the three-dimensional model of the oxidation ditch are extracted from ANSYS fluent.

[0062] It should be noted that, taking the A / A / O oxidation ditch of a sewage treatment plant with a treatment scale of 40000 m³ / d as an example, the size of the pool body is 110 m x 35 m x 6 m, and the initial mixed liquid suspended solid concentration can be specifically: using Realizable k-ε turbulence model and Eulerian multiphase flow model, the MLSS (initial mixed liquid suspended solid concentration) concentration of the sewage inlet and the reflux is set to 50-300 mg / L and 10000-15000 mg / L respectively; using coupled pressure-velocity coupling algorithm; the convergence residual of Fluent is less than 1 x 10⁻³.

[0063] Step 140, send the distribution data, velocity field and sludge concentration distribution data of the current sludge in the oxidation ditch three-dimensional model to the preset expert terminal, and obtain the returned running parameters of the agitator and the pusher.

[0064] It should be noted that the running parameters at least include the impeller diameter, angle, speed and installation position of the agitator and the pusher.

[0065] In some embodiments, the present step can be specifically:

[0066] S1, send the distribution data, velocity field and sludge concentration distribution data of the current sludge in the oxidation ditch three-dimensional model to all preset expert terminals.

[0067] S2, broadcast the first returned running parameters of the agitator and the pusher to all preset expert terminals.

[0068] S3, obtain the running parameter evaluation results; when more than a preset proportion of the running parameter evaluation results are reasonable, determine the current running parameters of the agitator and the pusher as the final running parameters of the agitator and the pusher.

[0069] S4, when no more than a preset proportion of the running parameter evaluation results are reasonable, obtain the running parameters uploaded by the expert terminal whose running parameter evaluation result is unreasonable.

[0070] S5, based on the preset weight of the unreasonable expert terminal, broadcast the running parameters of the expert terminal with the maximum preset weight to all preset expert terminals; obtain the running parameter evaluation results.

[0071] S6, cycle S3-S5 until more than a preset proportion of the running parameter evaluation results are reasonable, and determine the current running parameters of the agitator and the pusher as the final running parameters of the agitator and the pusher.

[0072] S7, increase the preset weight of the uploading expert terminal corresponding to the final running parameters of the agitator and the pusher by a preset first weight value; increase the preset weight of the expert terminal whose returned final running parameters of the agitator and the pusher are reasonable by a preset second weight value.

[0073] Wherein, preset first weight value > preset second weight value.

[0074] It should be noted that the initial weight can be 1.

[0075] Step 150, using the oxidation ditch three-dimensional model, simulating the angle and speed of the pusher and the agitator under different water flow data to meet the preset flow field flow state, and saving in the simulated flow field flow state database.

[0076] As an example, this step can be specifically:

[0077] In ANSYS fluent, set the water flow as a variable; for each set water flow value, adjust the angle and speed of the pusher and the agitator, and perform simulation calculation until the angle and speed combination that meets the preset flow field flow state is found; record the corresponding angle and speed combination of the pusher and the agitator under each water flow; organize the recorded data into a simulated flow field flow state database.

[0078] Wherein, the simulated flow field flow state database contains water flow data, pusher angle, pusher speed, agitator angle, and agitator speed.

[0079] Step 160, collecting the water flow data detected by the pre-positioned flow meter in the actual oxidation ditch corresponding to the oxidation ditch three-dimensional model, and according to the actual water flow data, obtaining the corresponding angle and speed of the pusher and the agitator from the simulated flow field flow state database, and returning to the oxidation ditch running equipment control terminal.

[0080] In addition, in order to avoid the change of the oxidation ditch in the later stage so that the three-dimensional model no longer fits, the present application can obtain the feedback returned by the terminal, and determine the adjustment time according to the feedback.

[0081] The specific implementation process can be:

[0082] After returning to the oxidation ditch running equipment control terminal, the adjusted oxidation ditch adjustment result returned by the oxidation ditch running equipment control terminal is obtained; wherein, the adjustment result at least contains whether the sludge concentration is reduced after a preset waiting time period; when the sludge concentration is not reduced after the preset waiting time period, a maintenance task is generated to the preset model maintenance terminal to correct the oxidation ditch three-dimensional model and the corresponding simulated flow field flow state database.

[0083] As an example, for a sewage treatment plant 40000 m³ / d treatment scale A / A / O oxidation ditch, the pool size is 110 m x 35 m x 6 m, and the grid division data and boundary conditions can also be specific: using a mixed grid form, 3D total grid number 1.9-2.3 million, and then migrating to other equipment CFD simulation; Local encryption in near-wall, aeration area, agitator and flow pusher, set 3 layers of boundary layer grid; The water inlet is set as a flow rate inlet (v = 0.5-0.8 m / s); The outlet weir is set as a pressure outlet; The reflux port is set as a velocity inlet (reflux ratio 40-80%). Among them, the initial mixed liquor suspended solids concentration can be specific: using Realizable k-ε turbulence model and Eulerian multiphase flow model, sewage inlet and reflux are set to MLSS (initial mixed liquor suspended solids concentration) concentration 50-300 mg / L and 10,000-15,000 mg / L respectively; Using coupled pressure-velocity coupling algorithm; The convergence residual of Fluent is less than 1x10⁻³. Verify the optimization effect through the operation data of the past year: sludge outlet concentration and measured concentration of effluent; The sludge concentration or dissolved oxygen data in the specific area are compared. The sludge distribution before optimization is shown in Figure 4 , and the sludge distribution after optimization is shown in Figure 5 It can be seen that the volume ratio of sludge concentration in the 4500-5000 mg / L segment after optimization is increased from 75.28% to 90.89%, which is about 20% higher than the former; The sludge concentration in the 4900-5000 mg / L segment is increased from 37.22% to 57.08%, which is about 53% higher than the former.

[0084] In addition, the present application Figure 6 The oxidation ditch optimization system based on computational fluid dynamics simulation provided by the embodiment of the present application. As Figure 6 The system provided by the embodiment of the present application mainly includes:

[0085] The establishment module 210 is used to obtain the oxidation ditch structure parameters, and then establish the corresponding oxidation ditch three-dimensional model; wherein the oxidation ditch structure parameters at least include: the geometric parameters of the middle partition wall, the flow guide wall, the aeration device, the agitator and the flow pusher.

[0086] The update module 220 is used to obtain the grid division data and boundary conditions of the three-dimensional model of the oxidation ditch through the CFD software ANSYS fluent, and update the three-dimensional model of the oxidation ditch; wherein the boundary conditions include: the simulation operation parameters of the water inlet, the outlet weir and the reflux port in the three-dimensional model.

[0087] The updating module 220 comprises an updating unit configured to import the three-dimensional model of the oxidation ditch into the ANSYS fluent software; read grid division data of the three-dimensional model of the oxidation ditch based on a preset reading address, and configure the grid division data into the current ANSYS fluent software; wherein the grid division data of the three-dimensional model of the oxidation ditch at least comprises grid type, grid size, grid density and grid distribution of each region in the three-dimensional model; read boundary conditions based on a preset reading address, and configure the boundary conditions into the current ANSYS fluent software.

[0088] The obtaining module 230 is configured to set initial mixed liquor suspended solids concentration of the water inlet and the backflow corresponding to the turbulent flow condition, and then obtain distribution data, velocity field and sludge concentration distribution data of sludge in the three-dimensional model of the oxidation ditch by using the Realizable k-ε turbulent flow model and the Eulerian multiphase flow model; send the distribution data, velocity field and sludge concentration distribution data of the current sludge in the three-dimensional model of the oxidation ditch to a preset expert terminal, and obtain returned operation parameters of the agitator and the plug flow device; wherein the operation parameters at least comprise impeller diameter, angle, rotating speed and installation position of the agitator and the plug flow device; simulate the angle and rotating speed of the plug flow device and the agitator under different water flow data to meet the preset flow field flow state by using the three-dimensional model of the oxidation ditch, and save in a simulated flow field flow state database.

[0089] The obtaining module 230 comprises an obtaining unit configured to set initial mixed liquor suspended solids concentration of the water inlet and the backflow in the ANSYS fluent; select the Realizable k-ε turbulent flow model in the model selection of the ANSYS fluent; simultaneously select the Eulerian multiphase flow model to simulate the interaction between sludge and water; start the solver of the ANSYS fluent, and perform simulation calculation according to the set initial mixed liquor suspended solids concentration, the Realizable k-ε turbulent flow model and the Eulerian multiphase flow model; after the simulation calculation is completed, extract distribution data, velocity field and sludge concentration distribution data of sludge in the three-dimensional model of the oxidation ditch from the ANSYS fluent.

[0090] The running module 240 is configured to collect water flow data detected by a pre-positioned flowmeter in the actual oxidation ditch corresponding to the three-dimensional model of the oxidation ditch, obtain corresponding angle and rotating speed of the plug flow device and the agitator from the simulated flow field flow state database according to the actual water flow data, and return to an oxidation ditch running equipment control terminal.

[0091] In addition, the embodiment of the present application further provides a non-volatile computer storage medium, which stores executable instructions, and when the executable instructions are executed, the oxidation ditch optimization method based on computational fluid dynamics simulation is realized.

[0092] So far, the technical solutions of the present disclosure have been described in combination with the foregoing embodiments, but those skilled in the art can easily understand that the protection scope of the present disclosure is not limited to these specific embodiments. Without deviating from the technical principles of the present disclosure, those skilled in the art can split and combine the technical solutions in the above-described embodiments, or make equivalent changes or replacements to related technical features, and any changes, equivalent replacements, improvements, etc. made within the technical concept and / or technical principles of the present disclosure will fall within the protection scope of the present disclosure.

Claims

1. A method for oxidation ditch optimization based on computational fluid dynamics simulation, characterized by, The method comprises: obtaining oxidation ditch structure parameters, and then establishing a corresponding oxidation ditch three-dimensional model; wherein the oxidation ditch structure parameters at least include the geometric parameters of the mid-partition wall, the flow guide wall, the aeration device, the agitator and the flow pusher; obtaining the grid division data and the boundary conditions of the three-dimensional model of the oxidation ditch by the CFD software ANSYS fluent, updating the three-dimensional model of the oxidation ditch; wherein the boundary conditions include the simulation operation parameters of the water inlet, the water weir and the backflow in the three-dimensional model; setting the initial mixed liquid suspended solid concentration of the water inlet and the backflow corresponding to the turbulent condition, and then obtaining the distribution data, the velocity field and the sludge concentration distribution data of the sludge in the three-dimensional model of the oxidation ditch by using the Realizable k-ε turbulent model and the Eulerian multiphase flow model; sending the distribution data, the velocity field and the sludge concentration distribution data of the current sludge in the three-dimensional model of the oxidation ditch to the preset expert terminal, and obtaining the returned operation parameters of the agitator and the flow pusher; wherein the operation parameters at least include the impeller diameter, the angle, the rotating speed and the installation position of the agitator and the flow pusher; specifically including: S1, sending the distribution data, the velocity field and the sludge concentration distribution data of the current sludge in the three-dimensional model of the oxidation ditch to all the preset expert terminals; S2, broadcasting the operation parameters of the agitator and the flow pusher returned first to all the preset expert terminals; S3, obtaining the operation parameter evaluation results; when more than a preset proportion of the operation parameter evaluation results are reasonable, determining the current operation parameters of the agitator and the flow pusher as the final operation parameters of the agitator and the flow pusher; S4, when not more than a preset proportion of the operation parameter evaluation results are reasonable, obtaining the operation parameters uploaded by the expert terminal with an unreasonable operation parameter evaluation result; S5, based on the preset weight of the expert terminal with an unreasonable operation parameter, broadcasting the operation parameters of the expert terminal with the maximum preset weight to all the preset expert terminals, and obtaining the operation parameter evaluation results; S6, repeating S3-S5 until more than a preset proportion of the operation parameter evaluation results are reasonable, and determining the current operation parameters of the agitator and the flow pusher as the final operation parameters of the agitator and the flow pusher; S7, increasing the preset first weight value of the preset weight of the uploading expert terminal corresponding to the final operation parameters of the agitator and the flow pusher; and increasing the preset second weight value of the preset weight of the expert terminal returning the final operation parameters of the agitator and the flow pusher as reasonable; wherein the preset first weight value > the preset second weight value; using the three-dimensional model of the oxidation ditch to simulate the angle and the rotating speed of the flow pusher and the agitator under different water flow data to meet the preset flow field flow state, and saving in the simulation flow field flow state database; The water flow data detected by the front flow meter in the actual oxidation ditch corresponding to the three-dimensional model of the oxidation ditch is collected, and the corresponding angle and rotating speed of the push-flow device and the agitator are obtained from the simulation flow field flow state database according to the actual water flow data, and returned to the oxidation ditch operation equipment control terminal; the adjusted results of the oxidation ditch returned by the oxidation ditch operation equipment control terminal are obtained; wherein the adjusted results at least include whether the sludge concentration is reduced after a preset waiting time period; when the sludge concentration is not reduced after the preset waiting time period, a maintenance task is generated to the preset model maintenance terminal to correct the three-dimensional model of the oxidation ditch and the corresponding simulation flow field flow state database; The initial mixed liquor suspended solids concentration of the inlet and the backflow corresponding to the turbulent condition is set, and then the distribution data, velocity field and sludge concentration distribution data of the sludge in the three-dimensional model of the oxidation ditch are obtained by using the Realizable k-ε turbulence model and the Eulerian multiphase flow model, specifically including: Setting the initial mixed liquor suspended solids concentration of the inlet and the backflow in ANSYS fluent; In the model selection of ANSYS fluent, the Realizable k-ε turbulence model is selected; At the same time, the Eulerian multiphase flow model is selected to simulate the interaction between sludge and water; Start the solver of ANSYS fluent, and perform simulation calculation according to the set initial mixed liquor suspended solids concentration, Realizable k-ε turbulence model and Eulerian multiphase flow model; After the simulation calculation is completed, the distribution data, velocity field and sludge concentration distribution data of the sludge in the three-dimensional model of the oxidation ditch are extracted from ANSYS fluent.

2. The computational fluid dynamics simulation-based oxidation ditch optimization method of claim 1, wherein, Through the CFD software ANSYS fluent, the mesh division data and boundary conditions of the three-dimensional model of the oxidation ditch are obtained, and the three-dimensional model of the oxidation ditch is updated, specifically including: Importing the three-dimensional model of the oxidation ditch into the ANSYS fluent software; Based on the preset reading address, the mesh division data of the three-dimensional model of the oxidation ditch is read, and the mesh division data is configured into the current ANSYS fluent software; wherein the mesh division data of the three-dimensional model of the oxidation ditch at least includes the grid type, grid size, grid density and grid distribution of each region in the three-dimensional model; Based on the preset reading address, the boundary conditions are read, and the boundary conditions are configured into the current ANSYS fluent software.

3. The oxidation ditch optimization method based on computational fluid dynamics simulation according to claim 1, wherein the distribution data of the current sludge in the three-dimensional model of the oxidation ditch, the velocity field and the sludge concentration distribution data are sent to a preset expert terminal to obtain the returned operation parameters of the agitator and the pusher; wherein, The operating parameters at least include the impeller diameter, angle, rotating speed and installation position of the agitator and the push-flow device; specifically including: S1, the distribution data, velocity field and sludge concentration distribution data of the current sludge in the three-dimensional model of the oxidation ditch are sent to all preset expert terminals; S2, the operating parameters of the first returned agitator and push-flow device are broadcasted to all preset expert terminals; S3, the operating parameter evaluation results are obtained; when more than a preset proportion of the operating parameter evaluation results are reasonable, the operating parameters of the current agitator and push-flow device are determined as the final operating parameters of the agitator and the push-flow device; S4, when the evaluation results of the operation parameters of no more than a preset proportion are reasonable, obtaining the operation parameters uploaded by the expert terminal with an unreasonable evaluation result of the operation parameters; S5, based on a preset weight of the expert terminal with an unreasonable evaluation result, broadcasting the operation parameters of the expert terminal with the maximum preset weight to all preset expert terminals; obtaining the evaluation results of the operation parameters; S6, repeating S3-S5 until the evaluation results of the operation parameters of more than a preset proportion are reasonable, determining the operation parameters of the current agitator and pusher as the final operation parameters of the agitator and pusher; S7, increasing a preset first weight value to the preset weight of the uploading expert terminal corresponding to the final operation parameters of the agitator and pusher; increasing a preset second weight value to the preset weight of the expert terminal returning the final operation parameters of the agitator and pusher as reasonable; wherein, the preset first weight value > the preset second weight value.

4. The computational fluid dynamics simulation-based oxidation ditch optimization method of claim 1, wherein, Using the three-dimensional model of the oxidation ditch, the angles and speeds of the pusher and the agitator that meet the preset flow field flow state under different water flow data are simulated and saved in the simulation flow field flow state database, specifically including: In ANSYS fluent, set the water flow as a variable; For each set water flow value, adjust the angles and speeds of the pusher and the agitator, and perform simulation calculation until the angle and speed combination that meets the preset flow field flow state is found; Record the corresponding angle and speed combination of the pusher and the agitator under each water flow; Organize the recorded data into the simulation flow field flow state database; wherein, the simulation flow field flow state database contains water flow data, pusher angle, pusher speed, agitator angle, and agitator speed.

5. An oxidation ditch optimization system based on computational fluid dynamics simulation, characterized by, The system comprises: The establishment module is configured to obtain oxidation ditch structure parameters, and then establish a corresponding three-dimensional model of the oxidation ditch; wherein, the oxidation ditch structure parameters at least include: the geometric parameters of the partition wall, the flow guide wall, the aeration device, the agitator, and the pusher; The update module is configured to obtain the meshing data and boundary conditions of the three-dimensional model of the oxidation ditch by using the CFD software ANSYS fluent, and update the three-dimensional model of the oxidation ditch; wherein, the boundary conditions include: the simulation operation parameters of the water inlet, the water weir, and the reflux in the three-dimensional model; The obtaining module is configured to set the initial mixed liquid suspended solid concentration of the water inlet and the reflux corresponding to the turbulent condition, and then obtain the distribution data, velocity field, and sludge concentration distribution data of the sludge in the three-dimensional model of the oxidation ditch by using the Realizable k-ε turbulent model and the Eulerian multiphase flow model; send the current distribution data, velocity field, and sludge concentration distribution data of the sludge in the three-dimensional model of the oxidation ditch to the preset expert terminal, and obtain the returned operation parameters of the agitator and the pusher; Using the three-dimensional model of the oxidation ditch, the angles and speeds of the pusher and the agitator that meet the preset flow field flow state under different water flow data are simulated and saved in the simulation flow field flow state database; The running module is configured to collect water flow data detected by a front flow meter in an actual oxidation ditch corresponding to a three-dimensional model of the oxidation ditch, obtain corresponding angles and rotating speeds of the pusher and the agitator from a simulated flow field flow state database according to the actual water flow data, and return to an oxidation ditch running equipment control terminal; obtain an adjusted result of the oxidation ditch returned by the oxidation ditch running equipment control terminal; wherein the adjusted result at least includes whether the sludge concentration is reduced after a preset waiting time period; when the sludge concentration is not reduced after the preset waiting time period, a maintenance task is generated to a preset model maintenance terminal to correct the three-dimensional model of the oxidation ditch and the corresponding simulated flow field flow state database; The obtaining module includes an obtaining unit, An initial mixed liquor suspended solids concentration of the inlet and the backflow is set in ANSYS fluent; In the model selection of ANSYS fluent, a Realizable k-ε turbulence model is selected; An Eulerian multiphase flow model is selected at the same time to simulate the interaction between the sludge and the water; The solver of ANSYS fluent is started, and simulation calculation is performed according to the set initial mixed liquor suspended solids concentration, the Realizable k-ε turbulence model and the Eulerian multiphase flow model; After the simulation calculation is completed, distribution data, a velocity field and sludge concentration distribution data of the sludge in the three-dimensional model of the oxidation ditch are extracted from ANSYS fluent.

6. The computational fluid dynamics simulation-based oxidation ditch optimization system of claim 5, wherein, The updating module includes an updating unit, The three-dimensional model of the oxidation ditch is imported into ANSYS fluent software; Based on a preset reading address, grid division data of the three-dimensional model of the oxidation ditch is read, and the grid division data is configured to the current ANSYS fluent software; wherein the grid division data of the three-dimensional model of the oxidation ditch at least includes grid types, grid sizes, grid densities and grid distributions of each region in the three-dimensional model; Based on a preset reading address, boundary conditions are read, and the boundary conditions are configured to the current ANSYS fluent software.

7. A non-transitory computer storage medium, comprising, Computer instructions are stored thereon, and the computer instructions, when executed, implement an oxidation ditch optimization method based on computational fluid dynamics simulation according to any one of claims 1-4.

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