A matching method for guide vanes and outlet flow channels of low-lift pump stations

Abstract

The present invention discloses a method for matching a guide vane with a water outlet flow channel of a low-lift pump station, comprising: collecting original data of a target pump station, selecting a combination of the guide vane blade axial length, the guide vane outlet placement angle, and the guide vane outlet diameter combination adjustment by classification according to the original data; optimizing the combination of the guide vane blade axial length, the guide vane outlet placement angle, and the guide vane outlet diameter combination adjustment to obtain an optimal parameter combination scheme. The present invention improves the hydraulic performance of the guide vane, reduces the hydraulic loss of the water outlet flow channel, and improves the efficiency of the pump device.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic machinery optimization design, and in particular relates to a method for matching a guide vane and a water outlet channel of a low-lift pump station. Background Art

[0002] At present, low-lift pump stations are widely used in the fields of water resource allocation, scheduling, irrigation, and residential water supply in China. During the operation of the pump station, the guide vanes guide the water flow out of the impeller, reducing the circumferential velocity of the water flow from a larger value at the inlet to a value close to 0 at the outlet, thereby achieving the effect of energy recovery. At present, the research on guide vanes mainly focuses on the matching of energy recovery and the relationship with the impeller. There are still few studies on the matching of guide vanes and outlet flow channels. The guide vanes and outlet flow channels are still spliced ​​and combined with the guide vanes in the high-efficiency pump section and the outlet flow channels with excellent performance. However, due to the hydraulic coherence between the guide vanes and the outlet flow channel, this method cannot achieve the highest efficiency of the pump device. In order to further improve the efficiency of the pump device and broaden the efficient operation range of the pump device, it is necessary to match the guide vanes and the outlet flow channel. Summary of the invention

[0003] In order to solve the above technical problems, the present invention proposes a method for matching the guide vanes and the outlet flow channel of a low-lift pump station, so as to improve the hydraulic performance of the guide vanes, reduce the hydraulic loss of the outlet flow channel, and improve the efficiency of the pump device.

[0004] To achieve the above object, the present invention provides a method for matching a guide vane and a water outlet flow channel of a low-lift pump station, comprising: collecting original data of a target pump station, and selecting a combination mode of combining and adjusting the guide vane blade axial length, the guide vane outlet placement angle, and the guide vane outlet diameter by classification according to the original data;

[0005] The combination of the guide vane blade axial length, the guide vane outlet placement angle and the guide vane outlet diameter combination adjustment is optimized to obtain the optimal parameter combination solution.

[0006] Optionally, the original data of the target pump station includes: the designed flow rate, designed head, three-dimensional structure of the impeller, guide vane parameters and three-dimensional structure of the flow channel of the target pump station.

[0007] Optionally, the combination of the guide vane blade axial length, the guide vane outlet placement angle and the guide vane outlet diameter combination adjustment includes:

[0008] The combination of the guide vane blade axial length, the guide vane outlet placement angle and the guide vane outlet diameter includes: a single combination, a two-factor combination or a three-factor combination.

[0009] Optionally, the classification method for selecting the combination of the guide vane blade axial length, the guide vane outlet placement angle and the guide vane outlet diameter combination adjustment includes:

[0010] The classification algorithm builds a classification model based on the data stored in the database, and determines the combination and threshold range of the guide vane blade axial length, guide vane outlet installation angle and guide vane outlet diameter according to the similarity between the pump type, flow channel form and the distribution of the residual velocity circulation at the guide vane outlet and the data stored in the database.

[0011] Optionally, the method of optimizing the combination of the guide vane blade axial length, the guide vane outlet placement angle and the guide vane outlet diameter combination adjustment to obtain the optimal parameter combination scheme includes:

[0012] The axial length of the guide vane blade, the guide vane outlet placement angle and the guide vane outlet diameter are sampled, a pump device calculation domain entity model is established and simulation calculation is performed to obtain calculation results; the nonlinear correlation of the threshold parameters in the calculation results is fitted, and the fitted nonlinear correlation is optimized through an intelligent optimization algorithm to obtain the optimal parameter combination scheme of the axial length of the guide vane blade, the guide vane outlet placement angle and the guide vane outlet diameter.

[0013] Optionally, the data stored in the database includes:

[0014] Pump station data includes design flow, design head, runner 3D structure, guide vane parameters and flow channel 3D structure;

[0015] Pump station operation calculation data include pump efficiency, hydraulic loss and residual circulation distribution at the guide vane outlet;

[0016] Pump station guide vane and outlet flow channel matching solution data.

[0017] Optionally, the method for sampling the axial length of the guide vane blade, the guide vane outlet installation angle and the guide vane outlet diameter is: according to the threshold range and combination of the axial length of the guide vane blade, the guide vane outlet installation angle and the guide vane outlet diameter, according to the data stored in the database, adjust within the limited optimization parameter threshold range, and sample the optimization variables.

[0018] Optionally, the method for fitting the nonlinear correlation of threshold parameters in the calculation results includes: generating a solid model of the pump device calculation domain according to the obtained sampling points, performing simulation calculations, transmitting the calculation results to a database, and simultaneously establishing an approximate model based on the calculation results to fit the nonlinear correlation between the calculation results and the optimization variables.

[0019] Optionally, the method of optimizing the fitted nonlinear correlation through an intelligent optimization algorithm to obtain the optimal combination of the axial length of the guide vane blade, the outlet placement angle of the guide vane blade and the outlet diameter of the guide vane includes: optimizing the fitted nonlinear correlation through an intelligent optimization algorithm to obtain the optimal solution under the combination, and obtaining the final solution through comparison; if the classification program obtains only one combination, the optimal solution obtained by the optimization subsystem is the final solution.

[0020] Optionally, the final solution includes a guide vane outlet diameter D gvo Equal to the inlet diameter of the outlet flow channel, adjust the guide vane outlet diameter D gvo , and update the outlet channel inlet diameter size synchronously.

[0021] Technical effect of the invention: The invention discloses a method for matching guide vanes and water outlet channels of a low-lift pump station, which integrates the matching methods of guide vanes and water outlet channels; for various pump types and various water outlet channel forms of low-lift pump stations, a more suitable guide vane parameter combination method can be found according to the similarity of their types or guide vane outlet axial velocity distribution forms with the help of a database and a classification program, thereby reducing the amount of calculation in the entire matching process and improving its accuracy; selecting optimization parameters according to the determined guide vane parameter combination method, and determining the optimization parameter threshold according to the database, and quickly finding the optimal solution with the help of an intelligent optimization algorithm, thereby avoiding the influence of manual experience in the matching design, and quickly and accurately obtaining the design scheme of the guide vanes and the water outlet channel, which not only saves the training cycle of designers but also can improve the water flow state of the guide vanes and the water outlet channel to the greatest extent, reduce the overall hydraulic loss of the pump device, and improve the overall efficiency of energy recovery of the guide vanes and the water outlet channel, thereby improving the efficiency of the pump device and broadening the high-efficiency operation area of ​​the pump device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0023] Figure 1 A schematic flow chart of a method for matching guide vanes and outlet channels of a low-lift pump station according to an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of a pump device according to an embodiment of the present invention;

[0025] Figure 3 is the axial length L of the guide vane in the embodiment of the present invention gv Adjustment diagram;

[0026] Figure 4 This is a schematic diagram of adjusting the guide vane outlet placement angle β according to an embodiment of the present invention;

[0027] Figure 5 is the guide vane outlet diameter D of the embodiment of the present invention gvo Adjustment diagram;

[0028] Among them, 1 is the water inlet channel; 2 is the impeller; 3 is the impeller blade; 4 is the guide vane; 5 is the guide vane blade; 6 is the water outlet channel; (a), (b), (c), (d) are the axial lengths L of the guide vane blades gv (e) and (f) are the design schemes for the guide vane outlet placement angle β; (g), (h), and (i) are the guide vane outlet diameter D gvo design plan. DETAILED DESCRIPTION

[0029] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0030] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0031] like Figure 1 As shown, this embodiment provides a method for matching the guide vanes of a low-lift pump station with the outlet flow channel, including: step one, collecting the original pump station data such as the design flow, design head, three-dimensional structure of the impeller, guide vane parameters and three-dimensional structure of the flow channel. Figure 2 This is a schematic diagram of the pump device structure used in the embodiment of the present invention, where 1, 2, 4, and 6 are respectively the water inlet channel, the impeller, the guide vane, and the water outlet channel, which are assembled together to form a pump device, used to illustrate the pump structure and channel type used in the embodiment of the present invention, and to indicate some data required for classification. 3 and 5 are respectively the blades welded on the impeller and the guide vane. Figure 3 (a), (b), (c), (d) are the axial lengths L of the guide vanes gv Different parameter schemes, wherein (d) is the initial axial length of the guide vane blades of the original pump station in the embodiment of the present invention; Figure 4 (e) and (f) are different parameter schemes for the guide vane outlet placement angle β, where (e) is the initial guide vane outlet placement angle of the original pump station in the embodiment of the present invention, Figure 5 (g), (h), (i) are the guide vane outlet diameters D gvo Different parameter schemes, where (g) is the initial guide vane outlet diameter of the original pump station in an embodiment of the present invention.

[0032] Step 2: According to the data in the database, three factors (L gv ,β,Dgvo ) Combination adjustment method. The axial length of the guide vane, the blade outlet placement angle and the guide vane outlet diameter are sampled; a solid model of the pump device calculation domain is established and CFD simulation calculation is performed; then the nonlinear correlation of the threshold parameters in the calculation results is fitted; the particle swarm algorithm is used to optimize the fitted nonlinear correlation to obtain the parameter combination scheme of (a)(f)(i).

[0033] The final design chosen is Figure 3 , 4 , 5 show the guide vane blade axial length (a), blade outlet placement angle (f) and guide vane outlet diameter (i).

[0034] Specifically,

[0035] (1) Collect pump station data such as design flow, design head, runner three-dimensional structure, guide vane parameters and flow channel three-dimensional structure, pump station operation calculation data such as pump efficiency, hydraulic loss and guide vane outlet residual circulation distribution, and record data of matching schemes.

[0036] (2) Due to the axial length L of the guide vane gv , guide vane outlet placement angle β, guide vane outlet diameter D gvo The influence on the pump device has a self-interference effect, so a classification program is needed to select the most appropriate parameter combination, and the axial length L of the guide vane gv , guide vane outlet placement angle β, guide vane outlet diameter D gvo The parameters can be freely combined, such as: single combination, two-factor combination, three-factor combination, and a more suitable combination method can be obtained according to the classification algorithm built into the classification program. Therefore, it is necessary to build a classification model based on the data stored in the database, and classify the original data of the target pump station by the similarity between the residual velocity loop at the guide vane outlet in the model and the built-in algorithm, and obtain a more suitable guide vane parameter combination method under the original data, which is used to determine the parameter combination method of the guide vane blade axial length, guide vane blade outlet placement angle and guide vane outlet diameter, so as to reduce the amount of calculation in the optimization subsystem process.

[0037] (3) The threshold ranges of parameters such as the axial length of the guide vane blade, the outlet placement angle of the guide vane blade, and the outlet diameter of the guide vane are adjusted within the limited threshold range of the optimization parameters according to the original data of the pump device and the combination of the guide vane parameters, and the optimization variables are sampled according to the data stored in the database.

[0038] (4) Generate a solid model of the pump device calculation domain according to the obtained sampling points, perform CFD simulation calculations, transfer the calculation results to the database, and simultaneously establish an approximate model based on the calculation results to fit the nonlinear correlation between the calculation results and the optimization variables.

[0039] (5) The optimal solution under the combination mode is obtained by optimizing the fitted nonlinear correlation through the intelligent optimization algorithm, and the final solution is obtained through comparison. If the combination mode obtained by the classification program is only one, the optimal solution obtained by the optimization subsystem is the final solution.

[0040] In the above steps, the calculation domain entity model of the pump device is constructed according to the original pump station parameters. The threshold parameters are set differently according to the different original pump station data and different combinations. At the same time, the set threshold will be adjusted within the limited reasonable parameter threshold range to ensure the feasibility of the final solution.

[0041] In the above steps, the geometric dimensions of the guide vanes are automatically modified through rotating machinery design software such as BladeGen or CFturbo to update the calculation domain entity model of the pump device. At the same time, the guide vane outlet diameter D gvo The same as the outlet diameter of the water channel, adjust the guide vane outlet diameter D gvo , the inlet diameter of the outlet flow channel is updated synchronously, and the geometric parameters of the guide vanes and the outlet flow channel are changed accordingly. It is necessary to remodel the outlet flow channel through 3D design software such as Creo and Siemens NX, and update the calculation domain entity model of the pump device synchronously, and perform CFD simulation calculation through ANSYS software. The required data is derived from the CFD calculation results.

[0042] In the above steps, the intelligent optimization algorithm in the optimization system can adopt intelligent optimization algorithms such as ant colony algorithm, annealing algorithm, particle swarm algorithm, etc. The uses of intelligent optimization algorithms are divided into two categories:

[0043] First, it is used to adjust the parameters of decision tree, SVM, random forest and other models during the classification process of data in the database.

[0044] Secondly, the nonlinear correlation used to execute module fitting is optimized to obtain the optimal solution for different combinations.

[0045] The present invention discloses a method for matching guide vanes and water outlet channels of a low-lift pump station, which integrates the matching methods of guide vanes and water outlet channels; for various pump types and various water outlet channel forms of the low-lift pump station, a more suitable guide vane parameter combination method can be found according to the similarity of their types or guide vane outlet axial velocity distribution forms with the help of a database and a classification program, thereby reducing the amount of calculation in the entire matching process and improving its accuracy; optimizing parameters are selected according to the determined guide vane parameter combination method, and the optimization parameter threshold is determined according to the database, and the optimization is quickly searched with the help of an intelligent optimization algorithm, thereby avoiding the influence of manual experience in the matching design, and quickly and accurately obtaining the design scheme of the guide vanes and the water outlet channel, which not only saves the training cycle of designers but also can improve the water flow state of the guide vanes and the water outlet channel to the greatest extent, reduce the overall hydraulic loss of the pump device, and improve the overall efficiency of energy recovery of the guide vanes and the water outlet channel, thereby improving the efficiency of the pump device and widening the high-efficiency operation area of ​​the pump device.

[0046] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for matching the guide vanes and the outlet flow channel of a low-lift pump station, characterized in that: include: Collecting original data of the target pump station, and selecting a combination of guide vane blade axial length, guide vane outlet placement angle and guide vane outlet diameter combination adjustment through classification according to the original data; The classification methods for selecting the combination of the guide vane blade axial length, the guide vane outlet placement angle and the guide vane outlet diameter combination adjustment include: The classification algorithm builds a classification model based on the data stored in the database, and determines the combination and threshold range of the guide vane blade axial length, guide vane outlet placement angle and guide vane outlet diameter according to the type of pump, the flow channel form and the distribution of the residual velocity circulation at the guide vane outlet similar to the data stored in the database; The combination mode of selecting the combined adjustment of the guide vane blade axial length, the guide vane outlet placement angle and the guide vane outlet diameter is optimized to obtain the optimal parameter combination scheme, specifically including: sampling the guide vane blade axial length, the guide vane outlet placement angle and the guide vane outlet diameter, establishing a pump device calculation domain entity model and performing simulation calculation to obtain calculation results; fitting the nonlinear correlation relationship of the threshold parameters in the calculation results, optimizing the fitted nonlinear correlation relationship through an intelligent optimization algorithm to obtain the optimal parameter combination scheme of the guide vane blade axial length, the guide vane blade outlet placement angle and the guide vane outlet diameter; According to the threshold range and combination mode of the guide vane blade axial length, the guide vane outlet placement angle and the guide vane outlet diameter, adjustments are made within the limited optimization parameter threshold range according to the data stored in the database, and the optimization variables are sampled; a pump device calculation domain entity model is generated according to the obtained sampling points, simulation calculations are performed, the calculation results are transmitted to the database, and an approximate model is established according to the calculation results at the same time, and the nonlinear correlation between the calculation results and the optimization variables is fitted; the fitted nonlinear correlation is optimized by an intelligent optimization algorithm to obtain the optimal solution under the combination mode, and the final solution is obtained by comparison; if the combination mode obtained by the classification program is one, the optimal solution obtained by the optimization subsystem is the final solution.

2. The method for matching the guide vanes of a low-lift pump station with the outlet flow channel according to claim 1, characterized in that: The original data of the target pump station include: the designed flow rate, designed head, three-dimensional structure of the runner, guide vane parameters and three-dimensional structure of the flow channel of the target pump station.

3. The method for matching the guide vanes of a low-lift pump station with the outlet flow channel according to claim 1, characterized in that: The combination of the guide vane axial length, guide vane outlet placement angle and guide vane outlet diameter combination adjustment includes: The combination of the guide vane blade axial length, the guide vane outlet placement angle and the guide vane outlet diameter includes: a single combination, a two-factor combination or a three-factor combination.

4. The method for matching the guide vanes of a low-lift pump station with the outlet flow channel according to claim 1, characterized in that: The data stored in the database includes: Pump station data includes design flow, design head, runner 3D structure, guide vane parameters and flow channel 3D structure; Pump station operation calculation data include pump efficiency, hydraulic loss and residual circulation distribution at the guide vane outlet; Pump station guide vane and outlet flow channel matching solution data.

5. The method for matching the guide vanes and the outlet flow channel of a low-lift pump station according to claim 1, characterized in that: The final solution includes the guide vane outlet diameter D gvo Equal to the inlet diameter of the outlet flow channel, adjust the guide vane outlet diameter D gvo , and update the outlet channel inlet diameter size synchronously.

Images