Cyclone wide working condition control method based on numerical simulation

Abstract

The invention discloses a cyclone wide working condition control method based on numerical simulation, particularly relates to the technical field of grinding systems, and comprises a wide working condition cyclone and an algorithm model of the air volume of a circulating fan and the opening degree of an inlet turning plate of the cyclone. According to the cyclone wide working condition control method based on numerical simulation, in a cement grinding system, when the grinding system is in large-air-volume operation, the opening degree of an inlet air speed turning plate is increased, so that the inlet air speed of a cyclone body is kept stable and even reduced, and therefore it is guaranteed that the resistance of the cyclone body is not increased on the premise that the efficiency fluctuation is not large; when the grinding system is in low-air-volume operation, the opening degree of the inlet air speed turning plate is reduced, so that the inlet air speed of the cyclone cylinder body is kept stable and even is reduced and increased, and the efficiency of the cyclone cylinder body is not reduced on the premise that the resistance fluctuation is not large; by adopting the method, the adaptability of the cyclone cylinder to wide-working-condition operation of the grinding system can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of grinding systems, and more specifically, to a cyclone wide operating condition control method based on numerical simulation. Background Art

[0002] It is known that the main function of the cyclone is to collect the fine powder sorted by the powder classifier, and to guide the relatively clean airflow out, which is then pressurized by the circulating fan for the next round of sorting; therefore, the control method of the cyclone operating state is suitable for the gas-solid separation process in the grinding system; since the cyclone has the characteristics of high separation efficiency, simple structure and reliable operation, it plays an important role in the gas-solid separation of the grinding system, and the performance of the cyclone has an important influence on the energy saving and consumption reduction of the grinding system and the reliable operation of the system; for example, the efficiency control and resistance optimization of the cyclone can improve the performance and economy of the overall sorting system.

[0003] However, in the actual operation process, affected by the fluctuations in process parameters and external conditions, the speed of the circulating fan will change accordingly, and the system air volume will change accordingly, causing the operating state of the cyclone to often deviate from its design conditions; specifically: when the air volume is greater than the design conditions, although the separation efficiency of the cyclone may be slightly improved, it is accompanied by a significant increase in operating resistance, which will undoubtedly lead to an increase in grinding energy consumption; conversely, when the air volume is lower than the design conditions, although the operating resistance is reduced, the separation efficiency of the cyclone may also drop significantly, thereby increasing the circulation volume of fine powder in the system, and ultimately affecting the stable and reliable operation of the roller press system and the circulating fan.

[0004] Therefore, in view of this dynamically changing process environment, real-time control of the cyclone is realized; therefore, a cyclone wide operating condition control method based on numerical simulation is proposed as a further improvement to ensure that the cyclone always operates in the best state, flexibly respond to real-time changing operating conditions, and improve the overall efficiency and operation stability of the grinding system. Summary of the invention

[0005] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a cyclone wide operating condition control method based on numerical simulation to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions: a cyclone wide working condition control method based on numerical simulation,

[0007] The specific steps of the control method are as follows:

[0008] S1: The algorithm model of the circulating fan air volume and the cyclone inlet flap opening is obtained based on the numerical simulation model and the response surface model;

[0009] S2: The gas-solid two-phase flow model of the cyclone is established using the rocky coupling fluid method;

[0010] S3: Calculate the efficiency e and resistance d of the cyclone under rated air volume through the gas-solid two-phase flow model established in S2;

[0011] S4: Through the response surface model of S1, a regression model of cyclone collection efficiency and resistance with respect to the circulation fan air volume and the cyclone inlet flap opening is established; a central composite design is used: first conduct a corner point experiment, then add some experimental combinations, and then conduct a center point experiment;

[0012] S5: According to the experiment in S4, simulation calculations of corresponding parameter combinations are performed in the simulation model in S1, and the collection efficiency and resistance of the cyclone under each experimental condition are recorded respectively; finally, statistical software is used to perform data analysis;

[0013] S6: Perform regression analysis: construct a polynomial regression model for the cyclone inlet air volume and the cyclone inlet flap opening;

[0014] S7: Use the least squares method to estimate the model coefficients in S6 and evaluate the goodness of fit of the model;

[0015] S8: By cross-validating the accuracy of the model in S6 using different data sets, a relatively reliable polynomial regression model of the cyclone inlet air volume and the cyclone inlet flap opening is obtained;

[0016] S9: Read the circulating fan inlet and outlet pressure difference from the on-site pressure gauge data, which is the circulating fan resistance P. According to the performance curve of the circulating fan, the circulating fan air volume Q is obtained, which is the cyclone inlet air volume. Q is introduced into the formula to calculate the improved flap opening y'. The central control transmits the action signal to the electric actuator, and the electric actuator controls the flap to adjust the flap angle to the specified opening y'.

[0017] S10: After the flap is turned, the system resistance changes, and the process returns to S9; after several iterations, if the calculated flap opening changes less than 5% from the previous opening, the final calculated opening is considered.

[0018] S11: According to the polynomial regression model, the resistance of the cyclone at this time can be calculated;

[0019] S12: By embedding the above process steps into the grinding system control program through programming, the flap opening can be adjusted in real time according to the changes in on-site process parameters.

[0020] Furthermore, in said S4, the experimental design factors are determined to be set as: cyclone inlet air volume x, flap opening y.

[0021] Furthermore, in S5, the collection efficiency and resistance of the cyclone are used as response variables.

[0022] Furthermore, in S6, the polynomial regression model:

[0023] E=a0+a1x+a2y+a3x 2 +a4y 2 +a5xy;

[0024] D=β0+β1x+β2y+β3x 2 +β4y 2 +β5xy;

[0025] E represents the collection efficiency, D represents the resistance, x is the inlet air volume, y is the flap opening, and a and β are the parameters to be estimated.

[0026] Furthermore, in S8, after a relatively reliable polynomial regression model is obtained, E is assigned as the efficiency e of the cyclone under rated air volume, that is, e=a0+a1x+a2y+a3x 2 +a4y 2 +a5xy;

[0027] By transforming this formula, we can get the relationship between x and y: y=c0+c1x+c3x 2 .

[0028] Furthermore, in the above S9, Q is assigned to x in y=c0+c1x+c3x2, and the improved flap opening y' can be inversely calculated.

[0029] Furthermore, the air volume of the circulating fan is calculated based on the airflow performance curve provided by the circulating fan manufacturer or obtained through simulation calculation and the pressure difference monitored by the on-site grinding system.

[0030] Technical effects and advantages of the present invention:

[0031] According to the cyclone wide working condition control method based on numerical simulation provided by the present invention, in a cement grinding system, when the grinding system is in large air volume operation, the opening of the inlet wind speed flap is increased, so that the inlet wind speed of the cyclone body remains stable or even decreases, thereby ensuring that the resistance of the cyclone body does not increase under the premise of small fluctuation in efficiency;

[0032] When the grinding system is in low air volume operation, the opening of the inlet wind speed flap is reduced, so that the inlet wind speed of the cyclone body remains stable or even increases, thereby ensuring that the efficiency of the cyclone body does not decrease under the premise of small resistance fluctuations.

[0033] This method can improve the adaptability of the cyclone to the wide operating conditions of the grinding system, ensuring the stable and reliable operation of the roller press system and the circulating fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is the overall structural front view of the present invention.

[0035] Figure 2 It is a top view of the overall structure of the present invention.

[0036] Figure 3 It is a stereoscopic diagram of the overall structure of the present invention.

[0037] The accompanying drawings are marked as follows: 1. cyclone body; 2. inlet wind speed flap; 3. flap hinge structure; 4. drive motor; 5. reducer. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0039] As attached Figure 1 , Attachment Figure 2 and attached Figure 3 A cyclone wide working condition control method based on numerical simulation is shown in FIG.

[0040] The control method includes: a specially designed wide-operating-condition cyclone and an algorithm model of the air volume of the circulating fan and the opening of the cyclone inlet flap;

[0041] The specially designed wide-operating-condition cyclone comprises: a cyclone body 1, an inlet wind speed flap 2 and an electric actuator; and the electric actuator comprises: a flap hinge structure 3, a drive motor 4, and a reducer 5;

[0042] Among them, the electric actuator has a remote transmission function; the inlet wind speed flap 2 is installed at the air inlet on the top of the cyclone body 1, the output shaft of the drive motor 4 is connected to the input end of the reducer 5, and the output end of the reducer 5 is connected to the inlet wind speed flap 2 through the flap hinge structure 3; and then the drive motor 4 can control the flap opening of the inlet wind speed flap 2;

[0043] The control logic of the electric actuator is implemented according to the corresponding relationship model between the rotation speed of the cyclone and the circulating fan and the opening of the cyclone inlet flap;

[0044] For grinding system,

[0045] The specific steps of the control method are as follows:

[0046] S1: The algorithm model of the circulating fan air volume and the cyclone inlet flap opening is obtained based on the numerical simulation model and the response surface model;

[0047] The simulation model is used to calculate the efficiency and resistance parameters of different experimental points; the response surface model is used to establish an algorithm model of the efficiency parameters and resistance parameters with respect to the air volume and flap opening of the circulating fan;

[0048] S2: The gas-solid two-phase flow model of the cyclone is established by using the rocky coupling fluid method; so as to establish the fluid domain model of the cyclone;

[0049] S3: Calculate the efficiency e and resistance d of the cyclone under rated air volume through the gas-solid two-phase flow model established in S2;

[0050] S4: Using the response surface model of S1, a regression model of the cyclone collection efficiency and resistance with respect to the circulation fan air volume and the cyclone inlet flap opening is established;

[0051] Among them, the experimental design factors are determined to be set as: cyclone inlet air volume x, flap opening y;

[0052] Use a central composite design: first conduct a corner experiment, then add some experimental combinations, and then conduct a center experiment;

[0053] Example:

[0054] The experimental design factors are determined as follows: the inlet air volume of the cyclone x, the flap opening y, and five gradients are set for each factor:

[0055] Inlet air volume x: x1 = low, x2 = medium-low, x3 = medium, x4 = medium-high, x5 = high;

[0056] Flap opening y: y1 = small, y2 = medium-small, y3 = medium, y4 = medium-large, y5 = high;

[0057] Four corner point experiments:

[0058] (x1, y1) - the inlet air volume is low and the flap opening is small;

[0059] (x1,y5)-the inlet air volume is low and the flap opening is large;

[0060] (x5,y1)-the inlet air volume is high and the flap opening is small;

[0061] (x5,y5)-the inlet air volume is high and the flap opening is large;

[0062] Supplement eight experimental combinations:

[0063] (x1, y3) - inlet air volume is low, flap opening is medium;

[0064] (x5,y3)-inlet air volume is high, flap opening is medium;

[0065] (x3, y1) - the inlet air volume is medium and the flap opening is small;

[0066] (x3, y5) - the inlet air volume is medium and the flap opening is large;

[0067] (x2, y2) - the inlet air volume is medium-low, and the flap opening is medium-small;

[0068] (x2, y4) - the inlet air volume is medium-low, and the flap opening is medium-large;

[0069] (x4, y2) - the inlet air volume is medium-high, and the flap opening is medium-small;

[0070] (x4, y5) - the inlet air volume is medium-high, and the flap opening is large;

[0071] A set of center point experiments: select the middle level (x3,y3);

[0072] According to the above combination, a total of 13 experiments are required, and finally 13 corresponding sets of data are obtained:

[0073] (x1, y1, e1, d1);

[0074] (x1, y5, e1, d2);

[0075] (x5, y1, e1, d3);

[0076] (x5, y5, e1, d4);

[0077] (x1, y3, e1, d5);

[0078] (x5, y3, e1, d6);

[0079] (x3, y1, e1, d7);

[0080] (x3, y5, e1, d8);

[0081] (x2, y2, e1, d9);

[0082] (x2, y4, e1, d10);

[0083] (x4, y2, e1, d11);

[0084] (x4, y5, e1, d12);

[0085] (x3, y3, e1, d13);

[0086] S5: According to the experiment in S4, simulation calculations of corresponding parameter combinations are performed in the simulation model in S1 in sequence, and the collection efficiency and resistance of the cyclone under each experimental condition are recorded respectively;

[0087] Among them, the collection efficiency and resistance of the cyclone are used as response variables;

[0088] Finally, statistical software was used for data analysis;

[0089] S6: Perform regression analysis: construct a polynomial regression model for the cyclone inlet air volume and the cyclone inlet flap opening;

[0090] Among them, the polynomial regression model:

[0091] E=a0+a1x+a2y+a3x 2 +a4y 2 +a5xy;

[0092] D=β0+β1x+β2y+β3x 2 +β4y 2 +β5xy;

[0093] E represents the collection efficiency, D represents the resistance, x is the inlet air volume, y is the flap opening, and a and β are the parameters to be estimated;

[0094] S7: Use the least squares method to estimate the model coefficients in S6 and evaluate the goodness of fit of the model;

[0095] S8: By cross-validating the accuracy of the model in S6 using different data sets, a relatively reliable polynomial regression model of the cyclone inlet air volume and the cyclone inlet flap opening is obtained;

[0096] Among them, after obtaining a relatively reliable polynomial regression model, E is assigned to the efficiency e of the cyclone under rated air volume, that is, e = a0 + a1x + a2y + a3x 2 +a4y 2 +a5xy;

[0097] By transforming this formula, we can get the relationship between x and y: y=c0+c1x+c3x 2 ;

[0098] S9: Read the circulating fan inlet and outlet pressure difference from the on-site pressure gauge data, which is the circulating fan resistance P. According to the performance curve of the circulating fan, the circulating fan air volume Q is obtained, which is the cyclone inlet air volume; Q is introduced into the formula to calculate the improved flap opening y'.

[0099] The specific formula for importing Q is: assign Q to x in y=c0+c1x+c3x2, and then the improved flap opening y' can be calculated in reverse;

[0100] The central control transmits the action signal to the electric actuator, which controls the flap to adjust the flap angle to the specified opening y';

[0101] Among them, the electric actuator has a remote transmission function;

[0102] S10: After the flap is turned, the system resistance changes, and the process returns to S9; after several iterations, if the calculated flap opening changes less than 5% from the previous opening, the final calculated opening is considered.

[0103] S11: According to the polynomial regression model, the resistance of the cyclone at this time can be calculated;

[0104] S12: By embedding the above process steps into the grinding system control program through programming, the flap opening can be adjusted in real time according to the changes in on-site process parameters.

[0105] In a preferred embodiment, as shown in the attached Figure 1 , Attachment Figure 2 and attached Figure 3 As shown, the circulating fan air volume is obtained by calculating the air flow performance curve provided by the circulating fan manufacturer or obtained through simulation calculation and the pressure difference monitored by the on-site grinding system.

[0106] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0107] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A cyclone wide working condition control method based on numerical simulation, characterized in that: The specific steps of the control method are as follows: S1: The algorithm model of the circulating fan air volume and the cyclone inlet flap opening is obtained based on the numerical simulation model and the response surface model; S2: The gas-solid two-phase flow model of the cyclone is established by using the rocky coupling fluent method; S3: Calculate the efficiency e and resistance d of the cyclone under rated air volume through the gas-solid two-phase flow model established in S2; S4: Through the response surface model of S1, a regression model of cyclone collection efficiency and resistance with respect to the air volume of the circulating fan and the opening of the cyclone inlet flap is established; using the central composite design, a corner point experiment is first conducted, and then some experimental combinations are added, and then a center point experiment is conducted; S5: According to the experiment in S4, simulation calculations of corresponding parameter combinations are performed in the simulation model in S1, and the collection efficiency and resistance of the cyclone under each experimental condition are recorded respectively; finally, statistical software is used to perform data analysis; S6: Perform regression analysis: construct a polynomial regression model for the cyclone inlet air volume and the cyclone inlet flap opening; S7: Use the least squares method to estimate the model coefficients in S6 and evaluate the goodness of fit of the model; S8: By cross-validating the accuracy of the model in S6 using different data sets, a relatively reliable polynomial regression model of the cyclone inlet air volume and the cyclone inlet flap opening is obtained; S9: Read the inlet and outlet pressure difference of the circulating fan from the on-site pressure gauge data, which is the circulating fan resistance P. According to the performance curve of the circulating fan, the air volume Q of the circulating fan is obtained, which is the inlet air volume of the cyclone. Import Q into the formula to calculate the improved flap opening y'. The central control transmits the action signal to the electric actuator, which controls the flap to adjust the flap angle to the specified opening y'. S10: After the flap is turned, the system resistance changes, and the process returns to S9; after several iterations, if the calculated flap opening changes less than 5% from the previous opening, the final calculated opening is considered. S11: According to the polynomial regression model, the resistance of the cyclone at this time can be calculated; S12: By embedding the above process steps into the grinding system control program through programming, the flap opening can be adjusted in real time according to the changes in on-site process parameters.

2. According to claim 1, a cyclone wide working condition control method based on numerical simulation is characterized in that: In said S4, the experimental design factors are determined to be set as: cyclone inlet air volume x, flap opening y.

3. A cyclone wide working condition control method based on numerical simulation according to claim 2, characterized in that: In S5, the collection efficiency and resistance of the cyclone are used as response variables.

4. A cyclone wide working condition control method based on numerical simulation according to claim 3, characterized in that: In S6, the polynomial regression model: E=a0+a1x+a2y+a3x 2 +a4y 2 +a5xy; D=β0+β1x+β2y+β3x 2 +β4y 2 +β5xy; E represents the collection efficiency, D represents the resistance, x is the inlet air volume, y is the flap opening, and a and β are the parameters to be estimated.

5. A cyclone wide working condition control method based on numerical simulation according to claim 4, characterized in that: In S8, after a relatively reliable polynomial regression model is obtained, E is assigned to the efficiency e of the cyclone under rated air volume, that is, e = a0 + a1x + a2y + a3x 2 +a4y 2 +a5xy; By transforming this formula, we can get the relationship between x and y: y=c0+c1x+c3x 2 .

6. A cyclone wide working condition control method based on numerical simulation according to claim 5, characterized in that: In S9, Q is assigned to x in y=c0+c1x+c3x2, and the improved flap opening y' can be inversely calculated.

7. A cyclone wide working condition control method based on numerical simulation according to claim 6, characterized in that: The air volume of the circulating fan is calculated by providing the circulating fan manufacturer or obtaining the air flow performance curve through simulation calculation and monitoring the pressure difference of the on-site grinding system.

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