A method of dynamic simulation of a flexible belt conveyor system

Abstract

The application discloses a flexible belt conveyor system dynamics simulation method, comprising the following steps: step S1, building a physical model system, measuring in three modes of no-load start operation, load operation and belt material start operation, obtaining measured operation parameters and measured values of preset indexes; step S2, based on the physical model system, establishing a flexible belt conveyor simulation model and a material particle simulation model; step S3, based on the measured operation parameters, simulating and analyzing the flexible belt conveyor simulation model and the material particle simulation model in the three modes, obtaining simulation values of the preset indexes; step S4, comparing the corresponding measured values and simulation values, judging whether the deviation value is greater than 10%, if yes, optimizing the simulation model, repeating steps S3-S4. The simulation model established according to the application can truly simulate the running condition of the flexible belt conveyor, improve the accuracy of the simulation result and optimize the system design.

Description

Technical Field

[0001] This invention relates to the field of flexible belt conveyor technology, and more specifically to a dynamic simulation method for a flexible belt conveyor system. Background Technology

[0002] Existing technologies for system dynamics simulation analysis of belt conveyors typically simplify the belt conveyor system into a discrete model and then conduct simulation analysis on the discrete model. This simulation method has been applied in the system design calculations and simulations of trough belt conveyors and tubular belt conveyors, but it cannot solve the simulation problem of flexible belt conveyors. The main reasons include: First, trough belt conveyors or tubular belt conveyors are mainly driven from the head and tail, and even if there is a middle drive, it is very rare. In contrast, flexible belt conveyors are driven from the middle, and the driving force is distributed along the conveyor path. At the same time, the driving force of existing belt conveyors is generated by the belt wrapping around the rollers, and the circumferential force generated by the rotation of the rollers drives the belt. However, the driving wheel of a flexible belt conveyor is not wrapped around the belt. Its driving force relies on the friction generated by the contact and compression between the driving wheel and the side of the belt to drive the belt. Therefore, the existing simulation methods are not suitable for simulating flexible belt conveyors.

[0003] Secondly, conveyor belts have viscoelastic mechanical properties. The tension of the conveyor belt of a long-distance trough belt conveyor or tubular belt conveyor is directly proportional to the conveying distance. That is, the longer the conveying distance, the greater the belt tension. However, flexible belt conveyors are driven by multiple points in a distributed manner, and the tension of the conveyor belt is controlled within a certain range. It will not increase indefinitely with the increase of the conveying distance. This also makes the conveyor belt model in the existing simulation methods unsuitable for flexible belt conveying processes.

[0004] Currently, there is no proposed simulation method for the conveying system of flexible belt conveyors. Furthermore, in terms of simulation method verification, existing technologies only simulate and test core components, failing to address systemic simulation and testing issues. Summary of the Invention

[0005] The purpose of this invention is to provide a dynamic simulation method for a flexible belt conveyor system, so that the simulation model established based on this method can realistically simulate the operation of the flexible belt conveyor and improve the accuracy of the simulation results.

[0006] To address the aforementioned technical problems, this invention provides a dynamic simulation method for a flexible belt conveyor system, comprising the following steps: Step S1: Construct a model system for a flexible belt conveyor. Perform actual measurements on the model system under three operating modes: no-load start-up, load operation, and material-carrying start-up, to obtain the measured operating parameters and the measured values ​​of preset indicators. Step S2: Based on the flexible belt conveyor material model system, establish a simulation model of the flexible belt conveyor and a simulation model of the material particles; Step S3: Based on the measured operating parameters, the simulation analysis of the flexible belt conveyor simulation model and the material particle simulation model are performed under the three operating modes of no-load start-up operation, load operation and material start-up operation respectively, to obtain the simulated values ​​of the preset index; Step S4: Compare the corresponding measured value and the simulated value, and determine whether the deviation between the measured value and the simulated value is greater than 10%. If so, optimize the simulation model of the flexible belt conveyor and the simulation model of the material particles, and repeat steps S3-S4.

[0007] This invention provides a dynamic simulation method for a flexible belt conveyor system. First, it constructs a complete model system of the flexible belt conveyor from a systemic perspective, rather than simulating and testing only core components, thus addressing systemic simulation and testing issues. Simultaneously, it conducts field tests on the flexible belt conveyor model system under three operating modes: no-load start-up, load operation, and material-carrying start-up. The test results accurately reflect various operating conditions of the flexible belt conveyor, providing guidance for the subsequent establishment and optimization of the flexible belt conveyor dynamic simulation model. Second, based on the flexible belt conveyor model system, it establishes a simulation model of the flexible belt conveyor and a material particle simulation model, requiring simulation based on the flexible belt conveyor... The physical model system models the flexible belt conveyor at a 1:1 scale. The basic properties of the simulated material must also be identical to those of the actual material, maintaining consistency with the actual measurement process. This invention simulates the flexible belt conveyor simulation model and the material particle simulation model under three operating modes: no-load start-up, load operation, and material-carrying start-up. The measured and simulated values ​​of preset indicators under each operating mode are compared to evaluate the flexible belt conveyor simulation model and the material particle simulation model, allowing for timely optimization. This ensures that the optimized models accurately reflect the operating conditions of the flexible belt conveyor physical model system, guaranteeing the reliability of the simulation results. Furthermore, the optimized models can simulate and predict operating conditions that existing physical model systems cannot test, or new operating conditions, saving time and cost in building new physical model systems, solving the time-consuming and labor-intensive problem of physical model system testing, improving efficiency, and broadening the application scope of this invention.

[0008] Optionally, the preset index is the power of the drive motor or the tension of the conveyor belt.

[0009] Optionally, the measured operating parameters include the frequency of the drive motor, the coefficient of friction, the speed of the conveyor belt, the rotational speed of the head roller, the rotational speed of the tail roller, and the rotational speed of the drive wheel.

[0010] Optionally, the flexible belt conveyor model system is tested under no-load start-up operation mode, specifically including the following steps: Start the drive motor, close the feeding valve, and conduct an unloaded start-up test on the flexible belt conveyor material model system at the preset frequency of the drive motor. After stabilizing for a preset time, record the measured operating parameters and the measured values ​​of the preset indicators under the current working conditions.

[0011] Optionally, the flexible belt conveyor model system is tested under load operation and material start-up operation modes to obtain measured operating parameters and measured values ​​of preset indicators. Specifically, this includes the following steps: Start the drive motor and open the discharge valve. At the preset frequency of the drive motor and the preset opening degree of the discharge valve, conduct a load operation test on the flexible belt conveyor model system. After a preset stable operation time, record the measured operating parameters and the measured values ​​of the preset indicators under the current working conditions. Close the discharge valve and turn off the drive motor while there is still material on the conveyor belt. Then start the drive motor again and conduct a material-carrying start-up test on the flexible belt conveyor model system. After the material on the conveyor belt has been conveyed, turn off the drive motor and record the measured operating parameters and the measured values ​​of the preset indicators under the current working conditions.

[0012] Optionally, a material particle simulation model is established based on the flexible belt conveyor model system, specifically including the following steps: Step S211: Test the actual material in the flexible belt conveyor model system to obtain the basic property parameters and measured property parameters of the actual material; Step S212: Based on the obtained basic attribute parameters, establish a three-dimensional model of the material particles and a discrete element model of the material particles. The discrete element model of the material particles is the simulation model of the material particles. Simulation analysis is performed on the simulated material using simulation software to obtain the simulation property parameters of the simulated material. Step S213: Compare the corresponding simulation property parameters with the measured property parameters, and determine whether the deviation between the simulation property parameters and the measured property parameters is greater than 10%. If so, optimize the three-dimensional model of the material particles and the discrete element model of the material particles, and repeat steps S12-S213.

[0013] Optionally, the basic attribute parameters include the particle size distribution and bulk density of the actual material.

[0014] Optionally, the measured property parameters and the simulated property parameters include compacted density, natural angle of repose, sliding friction angle, and collapse angle.

[0015] Optionally, a simulation model of the flexible belt conveyor is established based on the aforementioned flexible belt conveyor physical model system, specifically including the following steps: Step S221: Measure the conveyor belt and drive wheel in the drive device of the flexible belt conveyor physical model system to obtain the measured attribute parameters of the conveyor belt and drive wheel, and establish a three-dimensional model of the conveyor belt and a three-dimensional model of the drive device. Step S222: Based on the tail roller, head roller and idler roller in the flexible belt conveyor model system, establish a three-dimensional model of the roller and a three-dimensional model of the idler roller, and assemble the three-dimensional model of the roller, the three-dimensional model of the idler roller, the three-dimensional model of the conveyor belt and the three-dimensional model of the drive device into one, to obtain the initial three-dimensional model of the flexible belt conveyor. Step S223: Based on the support and column in the flexible belt conveyor physical model system, establish a three-dimensional model of the support and a three-dimensional model of the column, and assemble the three-dimensional model of the support, the three-dimensional model of the column, and the initial three-dimensional model of the flexible belt conveyor into one to obtain a three-dimensional model of the flexible belt conveyor. Step S224: Mesh the three-dimensional model of the flexible belt conveyor to obtain the finite element model of the flexible belt conveyor. The finite element model of the flexible belt conveyor is the simulation model of the flexible belt conveyor.

[0016] Optionally, the measured property parameters of the conveyor belt include bandwidth, belt strength, belt weight, elastic modulus, and hardness.

[0017] Optionally, the simulation model of the flexible belt conveyor is simulated and analyzed under the no-load start-up operation mode to obtain the simulated values ​​of the preset index, specifically including the following steps: Step S311: Import the simulation model of the flexible belt conveyor into the simulation software, and set the material properties and boundary conditions of each component in the simulation model of the flexible belt conveyor. Step S312: Input the preset speed of the drive motor and start the simulation. After a preset time, determine whether the simulation result meets the convergence condition. If not, optimize the simulation model of the flexible belt conveyor and repeat steps S311-S312. If yes, obtain the simulated value of the preset index under the current working condition.

[0018] The simulation analysis of the flexible belt conveyor simulation model and the material particle simulation model under the load operation mode includes the following steps: Step S321: Import the 3D model of the conveyor belt and the simulation model of the material particles into the discrete element method (DIM) software, and set the parameters of the 3D model of the conveyor belt and the simulation model of the material particles so that the material particle generation point is located above the material receiving point of the conveyor belt; import the simulation model of the flexible belt conveyor into the finite element method (FEM) software, and set the material properties and boundary conditions of each component in the simulation model of the flexible belt conveyor; connect the DIM software and the FEM software through a coupler to establish a data transmission channel between the DIM software and the FEM software; Step S322: Input the preset value of the material quantity into the discrete element software, input the preset speed of the drive motor into the finite element software, and control the discrete element software and the finite element software to start the simulation; Step S323: Within a preset time step, the discrete element software calculates the force data based on the current node data and transmits the force data to the finite element software. The finite element software calculates new node data based on the force data and transmits the new node data to the discrete element software. Step S324: After a preset time, determine whether the simulation results in the finite element software and discrete element software meet the convergence condition. If not, repeat steps S321-S323. If yes, obtain the simulated value of the preset index under the current working condition.

[0019] Optionally, simulation analysis is performed on the simulation model of the flexible belt conveyor and the simulation model of the material particles under the material start-up operation mode, specifically including the following steps: Step S331: Import the 3D model of the conveyor belt and the simulation model of the material particles into the discrete element method (DEM) software; set the parameters of the 3D model of the conveyor belt and the simulation model of the material particles; and fill the material section of the conveyor belt with the material according to the preset material quantity value; import the simulation model of the flexible belt conveyor into the finite element method (FEA) software; and set the material properties and boundary conditions of each component in the simulation model of the flexible belt conveyor; connect the DEM software and the FEA software through a coupler to establish a data transmission channel between the DEM software and the FEA software. Step S332: Input the preset speed of the drive motor into the finite element software, and control the discrete element software and the finite element software to start the simulation; Step S333: Within a preset time step, the discrete element software calculates the force data based on the current node data and transmits the force data to the finite element software. The finite element software calculates new node data based on the force data and transmits the new node data to the discrete element software. Step S334: After a preset time, determine whether the simulation results in the finite element software and discrete element software meet the convergence condition. If not, repeat steps S321-S323; if yes, obtain the simulated value of the preset index under the current working condition.

[0020] Optionally, when the preset index is the power of the drive motor, obtaining the simulated value of the preset index under the current speed condition specifically includes the following steps: The driving force of the drive motor is obtained by searching in the search module, and the product of the driving force and the preset speed is the simulated power of the drive motor. Attached Figure Description

[0021] Figure 1 A flowchart of the dynamic simulation method for the flexible belt conveyor system provided by the present invention; Figure 2 This is a schematic diagram of the flexible belt conveyor model system constructed according to the present invention; Figure 3 A simplified diagram illustrating the force analysis of the drive wheel and conveyor belt during their motion. Figure 4 A flowchart for establishing a material particle simulation model based on a flexible belt conveyor model system; Figure 5 A flowchart for establishing a simulation model of a flexible belt conveyor based on a physical model system of a flexible belt conveyor; Figure 6 A flowchart for conducting simulation analysis on a flexible belt conveyor simulation model under no-load start-up operation mode to obtain simulated values ​​of preset indicators; Figure 7 A flowchart for performing simulation analysis on a flexible belt conveyor simulation model and a material particle simulation model under load operation mode to obtain simulated values ​​of preset indicators; Figure 8 A flowchart for conducting simulation analysis on a flexible belt conveyor simulation model and a material particle simulation model under the material start-up operation mode to obtain the simulated values ​​of preset indicators; in, Figures 2-3 The annotations in the accompanying drawings are explained as follows: 11-Receiving device; 12-Conveyor belt; 13-Tail roller; 14-Head roller; 15-Drive device; 151-Drive wheel; 16-Idler roller; 21-Hopper; 22-Discharge valve; 23-Discharge pipe; 31-Variable frequency drive control box; 32-Signal acquisition device; 33-PLC control cabinet; 34-Computer. Detailed Implementation

[0022] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] The terms "first" and "second" used in this article are used only for the convenience of describing two or more structures or components that are identical or similar in structure and / or function, and do not indicate any special limitation on order and / or importance.

[0024] The term "several" as used in this article refers to a number of uncertain quantities, usually two or more; and when "several" is used to indicate the quantity of certain components, it does not indicate the quantitative relationship between these components.

[0025] Please refer to Figure 1 , Figure 1 The flowchart shows the dynamic simulation method for the flexible belt conveyor system provided by this invention.

[0026] This invention provides a dynamic simulation method for a flexible belt conveyor system, comprising the following steps: Step S1: Build a model system for the flexible belt conveyor and conduct actual measurements on the model system under three operating modes: no-load start-up, load operation, and material start-up, to obtain the measured operating parameters and the measured values ​​of the preset indicators. Step S2: Based on the flexible belt conveyor material model system, establish a simulation model of the flexible belt conveyor and a simulation model of the material particles; Step S3: Based on the measured operating parameters, simulation analysis is performed on the simulation model of the flexible belt conveyor and the simulation model of the material particles under three operating modes: no-load start-up, load operation, and material start-up, to obtain the simulated values ​​of the preset indicators. Step S4: Compare the corresponding measured values ​​and simulated values, and determine whether the deviation between the measured values ​​and simulated values ​​is greater than 10%. If so, optimize the simulation model of the flexible belt conveyor and the simulation model of the material particles, and repeat steps S3-S4.

[0027] This invention provides a dynamic simulation method for a flexible belt conveyor system. First, it constructs a complete model system of the flexible belt conveyor from a systemic perspective, rather than simulating and testing only core components, thus addressing systemic simulation and testing issues. Simultaneously, it conducts field tests on the flexible belt conveyor model system under three operating modes: no-load start-up, load operation, and material-carrying start-up. The test results accurately reflect various operating conditions of the flexible belt conveyor, providing guidance for the subsequent establishment and optimization of the flexible belt conveyor dynamic simulation model. Second, based on the flexible belt conveyor model system, it establishes a simulation model of the flexible belt conveyor and a material particle simulation model, requiring simulation based on the flexible belt conveyor... The physical model system models the flexible belt conveyor at a 1:1 scale, and the basic properties of the simulated material must be identical to those of the actual material. To maintain consistency with the actual measurement process, this invention simulates the flexible belt conveyor simulation model and the material particle simulation model under three operating modes: no-load start-up, load operation, and material-carrying start-up. The measured and simulated values ​​of preset indicators under each operating mode are compared to evaluate the flexible belt conveyor simulation model and the material particle simulation model, allowing for timely optimization. This ensures that the optimized models accurately reflect the operating conditions of the flexible belt conveyor physical model system, guaranteeing the reliability of the simulation results. Furthermore, based on this flexible belt conveyor simulation model and the material particle simulation model, it is possible to simulate and predict operating conditions that existing physical model systems cannot test, or new operating conditions. This saves time and cost in building new physical model systems, solves the time-consuming and labor-intensive problem of physical model system testing, improves efficiency, and broadens the application scope of this invention.

[0028] The aforementioned preset indicators can be the power of the drive motor or the tension of the conveyor belt. The following explanation will use the power of the drive motor as an example.

[0029] Please refer to Figure 2 , Figure 2 This is a schematic diagram of the flexible belt conveyor model system constructed according to the present invention.

[0030] In this embodiment, the flexible belt conveyor material model system specifically includes a conveying unit, a feeding unit, and a control unit, specifically: The conveying unit includes a receiving device 11, a conveyor belt 12, a tail roller 13, a head roller 14, a drive unit 15, idlers 16, and a supporting steel structure, wherein: The conveyor belt 12 is wound around the tail roller 13 and the head roller 14. The conveyor belt 12 is 125 meters long, 1400 mm wide, and has a conveying distance of 62 m, which means the distance between the tail roller 13 and the head roller 14 is 62 m. The climbing height is 5 m. There are six drive units 15, four of which are located in the loading section of the conveyor belt 12 and two in the return section. The drive units 15 are distributed along the conveying path at certain intervals, which can be adjusted according to test requirements and are not limited here. Each drive unit 15 includes two drive motors, two drive wheels 151, and a drive bracket. The drive motors and drive wheels 151 are mounted on the drive bracket. The center of the drive wheel 151 is connected to the rotating shaft of the drive motor. The surface of the drive wheel 151 contacts the conveyor belt 12. The extrusion friction between the drive wheel 151 and the conveyor belt 12 provides the driving force for the movement of the conveyor belt 12. The power of a single drive motor can be 1.1kW, 1.5kW, or 2.2kW, and is not limited here. The receiving device 11 has a receiving port, and the conveyor belt 12 at the receiving point is in an open state, which facilitates the material to enter the interior of the conveyor belt 12 from the receiving device 11; The idler roller 16 serves to limit and support, ensuring that the conveyor belt 12, except at the receiving point, remains in a closed state. The steel support structure is used to fix the entire device to the ground, ensuring the structural stability of the system; The feeding unit includes a hopper 21, a discharge valve 22, and a discharge pipe 23. The hopper 21 is used to store materials for simulation tests. One end of the discharge pipe 23 is connected to the hopper 21, and the other end is connected to the receiving port of the receiving device 11. The material can enter the conveyor belt 12 completely through the discharge pipe 23 to prevent material spillage. By adjusting the opening of the discharge valve 22, the feeding rate can be changed to simulate working conditions with different material quantities. The control unit includes a frequency converter control box 31, a signal acquisition unit 32, a PLC control cabinet 33, and a computer 34. The number of frequency converter control boxes 31 is the same as the number of drive units 15. The frequency converter control box 31 is electrically connected to two drive motors in the corresponding drive unit 15 and is used to control the two corresponding drive motors. One end of the signal acquisition unit 32 is electrically connected to each sensor, and the other end is connected to the PLC control cabinet 33. Each sensor is used to obtain measured operating parameters, which will be described in detail later. The PLC control cabinet 33 communicates with the computer 34 via optical fiber.

[0031] Furthermore, in step S1, the measured operating parameters include the frequency of the drive motor, the coefficient of friction, the speed of the conveyor belt, the rotational speed of the head roller, the rotational speed of the tail roller, and the rotational speed of the drive wheel.

[0032] Specifically, the coefficient of friction is calculated as follows: Please combine Figure 3 understand, Figure 3A simplified force analysis diagram of the driving wheel 151 and the conveyor belt 12 during their motion is shown. There is one driving wheel 151 on each side, which clamps the conveyor belt 12. The rotation of the driving wheel 151 drives the conveyor belt 12 to move. The compressive friction between the drive wheel 151 and the conveyor belt 12 is the driving force for the movement of the conveyor belt 12. The compressive friction is calculated as follows:

[0033] In the formula: F r —Driving force of the drive unit, N; f r —Coefficient of friction; F p —The positive pressure between the drive wheel on one side and the conveyor belt, N; Since the conveyor belt 12 is in motion during the operation of the flexible belt conveyor model system, the normal pressure is calculated using the following formula. F p :

[0034] In the formula: F 1 —Weight of the conveyor belt and materials, in N; α —Angle between the drive wheel and the horizontal line; The friction coefficient can be obtained by combining the above calculation formulas. The formula for calculating the friction coefficient is:

[0035] In the formula, the included angle α and the driving force of the driving device are... F r The weight of the conveyor belt 12 and the material F 1 The friction coefficient can be obtained directly through sensors. Since multiple drive motors in the system jointly drive the entire system, the friction coefficient is calculated using a grouped method, with each group of drive motors forming a calculation unit.

[0036] Other measured operating parameters can be measured using corresponding sensors. For example, the frequency of the drive motor can be obtained by reading the data from the frequency converter; the speed of the conveyor belt can be measured using a belt speed sensor; and the speeds of the head roller, tail roller, and drive wheel can be measured using a speed sensor.

[0037] The power of the motor driven by the preset target can be calculated by multiplying the current and voltage of the motor. The current of the motor can be measured by a current transformer, and the voltage of the motor can be measured by a voltage transformer.

[0038] Meanwhile, when conveyor belt tension is used as an evaluation index, it can be measured using a non-contact tension meter.

[0039] Furthermore, the flexible belt conveyor model system was tested under no-load start-up operation mode, specifically including the following steps: Close the discharge valve 22, start the drive motor, and conduct an unloaded start-up test on the flexible belt conveyor model system at the preset frequency of the drive motor. After the system has been running stably for a preset time, record the measured operating parameters and the measured values ​​of the preset indicators under the current working conditions.

[0040] In the no-load start-up operation, the conveyor belt is empty. The preset frequency of the drive motor can be set to 10Hz, 20Hz, 30Hz, 40Hz, and 50Hz. For example, the initial frequency of the drive motor is first set to 10Hz, and the flexible belt conveyor model system is started. Each drive motor starts working and runs stably for a preset time. The measured operating parameters and the measured power of the drive motor under the 10Hz condition are recorded. Then, the frequency of the drive motor is changed, and the flexible belt conveyor model system is tested in turn under the 20Hz, 30Hz, 40Hz, and 50Hz conditions. The corresponding measured operating parameters and the measured power of the drive motor are recorded. After the test is completed, the drive motor is turned off, and the flexible belt conveyor model system stops running.

[0041] This embodiment conducts five experiments in the no-load start-up operation mode. Of course, the preset frequencies of the drive motor are not limited to the above setting method, and the running time of each preset frequency condition is not limited. It can be set according to actual needs.

[0042] Furthermore, the flexible belt conveyor model system was tested under load operation and material start-up operation modes to obtain measured operating parameters and measured values ​​of preset indicators. The specific steps included: Start the drive motor and open the discharge valve 22. At the preset frequency of the drive motor and the preset opening of the discharge valve 22, conduct a load operation test on the flexible belt conveyor model system. After a preset stable operation time, record the measured operating parameters and the measured values ​​of the preset indicators under the current working conditions. Close the discharge valve 22 and turn off the drive motor while there is still material on the conveyor belt 12. Then start the drive motor again and conduct a material start-up operation test on the flexible belt conveyor model system. After the material on the conveyor belt 12 has been conveyed, turn off the drive motor and record the measured operating parameters and the measured values ​​of the preset indicators under the current working conditions.

[0043] This step involves simultaneously conducting load operation and material-waiting start-up tests on the flexible belt conveyor model system under a specific working condition. The preset frequencies of the drive motors can be set to 10Hz, 20Hz, 30Hz, 40Hz, and 50Hz, and the preset opening degrees of the discharge valves can be set to 25%, 50%, 75%, and 100%. In practical applications, the drive motor frequency can be set to 10Hz first, the flexible belt conveyor model system can be started, and each drive motor can begin working. Then, the discharge valves can be opened, with an initial opening degree of 25%. After a preset stable operation time, the measured operating parameters of the load operation mode and the measured power of the drive motor under the current working condition can be recorded. The discharge valves can then be closed, and the drive motors can be turned off while there is still material on the conveyor belt. At this point, simply restarting the drive motors will allow for a material-carrying start-up test under the current working condition, obtaining the measured operating parameters and measured power of the drive motor under the current working condition.

[0044] By adjusting the preset frequency of the drive motor and the preset opening of the feeding valve, the measured operating parameters and measured power of the drive motor can be obtained under two modes: load operation and material start-up operation, at different preset frequency conditions and different preset openings. Specifically, the frequency of the drive motor can be kept at 10Hz, and the opening of the feeding valve can be changed. The flexible belt conveyor model system can be tested sequentially at openings of 50%, 75%, and 100%, and the corresponding measured operating parameters and measured power of the drive motor can be recorded. Then, the frequency of the drive motor can be changed sequentially to 20Hz, 30Hz, 40Hz, and 50Hz, and tests can be conducted under different opening conditions. In short, this embodiment will conduct tests on various feeding valve openings for each frequency condition of the drive motor in both load operation and material start-up operation modes.

[0045] Of course, in practical applications, the opening of the feeding valve can be kept at 25% first, and the frequency of the drive motor can be changed. The flexible belt conveyor material model system can be tested in turn at 20Hz, 30Hz, 40Hz and 50Hz, and the corresponding measured operating parameters and measured power of the drive motor can be recorded. Then, the opening of the feeding valve can be changed in turn to 50%, 75% and 100%, and the different drive motor frequencies can be tested. That is, the various different drive motor frequencies can be tested for each opening condition of the feeding valve 22.

[0046] Similarly, the preset opening values ​​of the feeding valve 22 are not limited and can be set according to actual needs.

[0047] Furthermore, in step S2, a material particle simulation model is established based on the flexible belt conveyor model system, specifically including the following steps: Step S211: Test the actual material in the model system of the flexible belt conveyor to obtain the basic property parameters and measured property parameters of the actual material; Step S212: Based on the obtained basic attribute parameters, establish a three-dimensional model of the material particles and a discrete element model of the material particles. The discrete element model of the material particles is the simulation model of the material particles. The simulation material is simulated and analyzed by simulation software to obtain the simulation property parameters of the simulated material. Step S213: Compare the corresponding simulation property parameters with the measured property parameters, and determine whether the deviation between the simulation property parameters and the measured property parameters is greater than 10%. If so, optimize the three-dimensional model and discrete element model of the material particles, and repeat steps S212-S213. Only when the deviation between the simulation property parameters and the measured property parameters is not greater than 10% can the material simulation model be considered qualified.

[0048] The basic attribute parameters include the particle size distribution and bulk density of the actual material. During the simulation analysis, the bulk density and particle size distribution of the simulated material should be consistent with those of the actual material.

[0049] Among them, the measured property parameters and simulated property parameters include compacted density, natural angle of repose, sliding friction angle and collapse angle. How to test the particle size distribution, bulk density, compacted density, natural angle of repose, sliding friction angle and collapse angle of actual materials is a well-known existing technology in the art, so it will not be described in detail here.

[0050] Furthermore, in step S2, a simulation model of the flexible belt conveyor is established based on the flexible belt conveyor physical model system, specifically including the following steps: Step S221: Measure the conveyor belt 12 and the drive wheel 151 in the drive device of the flexible belt conveyor physical model system to obtain the measured attribute parameters of the conveyor belt 12 and the drive wheel 151, and establish a three-dimensional model of the conveyor belt and a three-dimensional model of the drive device. Step S222: Based on the tail roller 13, head roller 14 and idler roller 16 in the model system of the flexible belt conveyor, establish the three-dimensional model of the roller and the three-dimensional model of the idler roller, and assemble the three-dimensional model of the roller, the three-dimensional model of the idler roller, the three-dimensional model of the conveyor belt and the three-dimensional model of the drive device into one, to obtain the initial three-dimensional model of the flexible belt conveyor. Step S223: Based on the support and column in the flexible belt conveyor physical model system, establish a three-dimensional model of the support and a three-dimensional model of the column, and assemble the three-dimensional model of the support, the three-dimensional model of the column, and the initial three-dimensional model of the flexible belt conveyor into one to obtain a three-dimensional model of the flexible belt conveyor. Step S224: Mesh the three-dimensional model of the flexible belt conveyor to obtain the finite element model of the flexible belt conveyor. The finite element model of the flexible belt conveyor is the simulation model of the flexible belt conveyor.

[0051] The measured properties of the conveyor belt 12 include its bandwidth, belt strength, belt weight, elastic modulus, and hardness. The specific testing methods are existing technologies well-known to those skilled in the art and will not be elaborated upon here. Furthermore, in step S224, the three-dimensional model of the flexible belt conveyor is meshed. This can be done using specialized meshing software, or the three-dimensional model of the flexible belt conveyor can be imported into finite element analysis software and meshed thereafter.

[0052] It should be noted that the "flexible belt conveyor model system" mentioned here means that each component in the flexible belt conveyor model system needs to be modeled at a 1:1 scale.

[0053] Furthermore, the simulation model of the flexible belt conveyor is analyzed under no-load start-up operation mode to obtain the simulated values ​​of the preset indicators. The specific steps include the following: Step S311: Import the simulation model of the flexible belt conveyor into the simulation software, and set the material properties and boundary conditions of each component in the simulation model of the flexible belt conveyor. Step S312: Input the preset speed of the drive motor and start the simulation. After a preset time, determine whether the simulation result meets the convergence condition. If not, optimize the simulation model of the flexible belt conveyor and repeat steps S311-S312. If yes, obtain the simulated value of the preset index under the current working condition.

[0054] The material properties of each component should be consistent with the actual material properties of each component in the flexible belt conveyor model system; the boundary conditions of each component are also set according to the actual situation, such as the boundary condition of the support steel structure being fixed; the boundary condition of the drive device 15 and the conveyor belt 12 being in contact with each other, and the friction coefficient obtained from the measured operating parameters is input to define the contact model; the boundary condition of the idler roller 16 and the conveyor belt 12 being in contact with each other, and the boundary condition of the conveyor belt 12 being in motion, etc.

[0055] During simulation, the preset speed of the drive motor should correspond one-to-one with the preset frequency of the drive motor during the no-load start-up test of the physical model system. For example, if the preset frequency of the drive motor during the no-load start-up test of the physical model system is 10Hz, 20Hz, 30Hz, 40Hz, or 50Hz, the corresponding preset speed can be obtained by using the conversion formula between motor speed and motor frequency. Each preset speed is then input into the simulation software for simulation. Taking the frequency of the drive motor as the preset index as an example, after the simulation, the driving force of the drive motor under different preset speed conditions can be found in the search module. The product of the driving force and the preset speed is the simulated power of the drive motor. At this point, the measured power and simulated power of the drive motor under the same working condition can be compared to determine whether the simulation model of the flexible belt conveyor and the simulation model of the material particles are qualified in the no-load start-up mode.

[0056] One way to determine whether the simulation results meet the convergence criteria is to judge whether the convergence curve is stable.

[0057] Furthermore, simulation analysis was conducted on the flexible belt conveyor simulation model and the material particle simulation model under load operation mode, specifically including the following steps: Step S321: Import the 3D model of the conveyor belt and the simulation model of the material particles into the discrete element software, and set the parameters of the 3D model of the conveyor belt and the simulation model of the material particles so that the material particle generation point is located above the material receiving point of the conveyor belt; import the simulation model of the flexible belt conveyor into the finite element software, and set the material properties and boundary conditions of each component in the simulation model of the flexible belt conveyor; connect the discrete element software and the finite element software through a coupler to establish a data transmission channel between the discrete element software and the finite element software; Step S322: Input the preset value of the material quantity in the discrete element software and the preset speed of the drive motor in the finite element software, and control the discrete element software and finite element software to start the simulation. Step S323: Within a preset time step, the discrete element software calculates the force data based on the current node data and transmits the force data to the finite element software. The finite element software then calculates new node data based on the force data and transmits the new node data to the discrete element software. Step S324: After a preset time, determine whether the simulation results in the finite element software and discrete element software meet the convergence conditions. If not, repeat steps S321-S323; if yes, obtain the simulated values ​​of the preset indicators under the current working conditions.

[0058] The setting of material properties and boundary conditions is the same as in the no-load operation mode, and will not be repeated here.

[0059] In step S322, the preset value of the input material quantity should be consistent with the value of the material quantity measured by the physical model system. For example, when the physical model system is measured in the load operation mode, the opening degree of the discharge valve 22 is 25%, 50%, 75%, and 100%. With the opening degree and discharge time known, the specific value of the material quantity corresponding to each opening degree can be calculated. The specific value of each material quantity is then input into the simulation software for simulation. Taking the frequency of the drive motor as the preset index as an example, after the simulation, the driving force of the drive motor under different preset opening conditions is obtained in the search module. The product of the driving force and the preset speed is the simulated power of the drive motor. At this time, the measured power and simulated power of the drive motor under the same operating condition can be compared to determine whether the simulation model of the flexible belt conveyor and the simulation model of the material particles are qualified in the load operation mode. The method for determining the preset speed of the drive motor is the same as that in the no-load operation mode, and will not be repeated here.

[0060] The preset time step needs to be set based on the computing performance of the simulation equipment, time cost, and actual working conditions. There is no specific limit to the exact value; for example, it can be set to 0.01s. In this case, the discrete element method (DEM) software calculates the force data every 0.01s and transmits the force data to the finite element method (FEA) software. The FEA software then calculates the nodal data based on the force data every 0.01s and transmits the new nodal data to the DEM software. This process repeats until the preset time is reached. The specific value of the preset time is also not limited.

[0061] Furthermore, the method for determining whether the simulation results meet the convergence criteria is the same as that used in the no-load operation mode, and will not be elaborated further here.

[0062] Furthermore, simulation analysis was conducted on the flexible belt conveyor simulation model and the material particle simulation model under the material start-up operation mode, specifically including the following steps: Step S331: Import the 3D model of the conveyor belt and the simulation model of the material particles into the discrete element software, and set the parameters of the 3D model of the conveyor belt and the simulation model of the material particles. According to the preset value of the material quantity, the material is filled in the loading section of the conveyor belt. Import the simulation model of the flexible belt conveyor into the finite element software, and set the material properties and boundary conditions of each component in the simulation model of the flexible belt conveyor. Connect the discrete element software and the finite element software through a coupler to establish a data transmission channel between the discrete element software and the finite element software. Step S332: Input the preset speed of the drive motor into the finite element software, and control the discrete element software and finite element software to start the simulation. Step S333: Within a preset time step, the discrete element software calculates the force data based on the current node data and transmits the force data to the finite element software. The finite element software then calculates new node data based on the force data and transmits the new node data to the discrete element software. Step S334: After a preset time, determine whether the simulation results in the finite element software and discrete element software meet the convergence conditions. If not, repeat steps S331-S334; if yes, obtain the simulated values ​​of the preset indicators under the current working conditions.

[0063] As can be seen, in the material-driven start-up mode and the load-driven operation mode, everything is the same except for the coupling method between the conveyor belt and the material, so it will not be elaborated here.

[0064] In addition, when the preset index is conveyor belt tension, this value can be directly obtained from the search module.

[0065] The above provides a detailed description of the dynamic simulation method for a flexible belt conveyor system provided by this invention. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of this invention. It should be noted that those skilled in the art can make various improvements and modifications to this invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of this invention.

Claims

1. A dynamic simulation method for a flexible belt conveyor system, characterized in that, Includes the following steps: Step S1: Construct a model system for a flexible belt conveyor. Perform actual measurements on the model system under three operating modes: no-load start-up, load operation, and material-carrying start-up, to obtain the measured operating parameters and the measured values ​​of preset indicators. Step S2: Based on the flexible belt conveyor material model system, establish a simulation model of the flexible belt conveyor and a simulation model of the material particles; Step S3: Based on the measured operating parameters, perform simulation analysis on the simulation model of the flexible belt conveyor in the no-load start-up operation mode, and perform simulation analysis on the simulation model of the flexible belt conveyor and the simulation model of the material particles in the load operation mode and the material start-up operation mode to obtain the simulated values ​​of the preset index. Step S4: Compare the corresponding measured value and the simulated value, and determine whether the deviation between the measured value and the simulated value is greater than 10%. If so, optimize the simulation model of the flexible belt conveyor and the simulation model of the material particles, and repeat steps S3-S4. The establishment of a simulation model of the flexible belt conveyor based on the aforementioned flexible belt conveyor physical model system includes the following steps: Step S221: Measure the conveyor belt (12) and drive wheel (151) in the drive device of the flexible belt conveyor physical model system to obtain the measured attribute parameters of the conveyor belt (12) and the drive wheel (151), and establish a three-dimensional model of the conveyor belt and a three-dimensional model of the drive device. Step S222: Based on the tail roller (13), head roller (14) and idler roller (16) in the model system of the flexible belt conveyor, establish a three-dimensional model of the roller and a three-dimensional model of the idler roller, and assemble the three-dimensional model of the roller, the three-dimensional model of the idler roller, the three-dimensional model of the conveyor belt and the three-dimensional model of the drive device into one unit to obtain the initial three-dimensional model of the flexible belt conveyor. Step S223: Based on the support and column in the flexible belt conveyor physical model system, establish a three-dimensional model of the support and a three-dimensional model of the column, and assemble the three-dimensional model of the support, the three-dimensional model of the column, and the initial three-dimensional model of the flexible belt conveyor into one to obtain a three-dimensional model of the flexible belt conveyor. Step S224: Mesh the three-dimensional model of the flexible belt conveyor to obtain the finite element model of the flexible belt conveyor. The finite element model of the flexible belt conveyor is the simulation model of the flexible belt conveyor.

2. The dynamic simulation method for the flexible belt conveyor system according to claim 1, characterized in that, The preset indicators are the power of the drive motor or the tension of the conveyor belt.

3. The dynamic simulation method for the flexible belt conveyor system according to claim 1, characterized in that, The measured operating parameters include the frequency of the drive motor, the coefficient of friction, the speed of the conveyor belt (12), the rotational speed of the head roller (14), the rotational speed of the tail roller (13), and the rotational speed of the drive wheel (151).

4. The dynamic simulation method for the flexible belt conveyor system according to claim 1, characterized in that, The flexible belt conveyor model system was tested under no-load start-up operation mode, specifically including the following steps: Close the feeding valve (22), start the drive motor, and conduct an unloaded start-up test on the flexible belt conveyor material model system at the preset frequency of the drive motor. After a preset stable operation time, record the measured operating parameters and the measured values ​​of the preset indicators under the current working conditions.

5. The dynamic simulation method for a flexible belt conveyor system according to claim 1, characterized in that, The flexible belt conveyor model system was tested under load operation and material start-up operation modes to obtain measured operating parameters and measured values ​​of preset indicators. The specific steps included: Start the drive motor and open the discharge valve (22). At the preset frequency of the drive motor and the preset opening of the discharge valve (22), conduct a load operation test on the flexible belt conveyor model system. After a preset stable operation time, record the measured operating parameters and the measured values ​​of the preset index under the current working condition. Close the discharge valve (22). When there is still material on the conveyor belt (12), turn off the drive motor. Then start the drive motor again and conduct a material start-up operation test on the flexible belt conveyor model system. When the material on the conveyor belt (12) is conveyed, turn off the drive motor and record the measured operating parameters and the measured values ​​of the preset index under the current working condition.

6. The dynamic simulation method for a flexible belt conveyor system according to claim 1, characterized in that, The process of establishing a material particle simulation model based on the flexible belt conveyor model system includes the following steps: Step S211: Test the actual material in the flexible belt conveyor model system to obtain the basic property parameters and measured property parameters of the actual material; Step S212: Based on the obtained basic attribute parameters, establish a three-dimensional model of the material particles and a discrete element model of the material particles. The discrete element model of the material particles is the simulation model of the material particles. Simulation analysis is performed on the simulated material using simulation software to obtain the simulation property parameters of the simulated material. Step S213: Compare the corresponding simulation property parameters with the measured property parameters, and determine whether the deviation between the simulation property parameters and the measured property parameters is greater than 10%. If so, optimize the three-dimensional model of the material particles and the discrete element model of the material particles, and repeat steps S212-S213.

7. The dynamic simulation method for a flexible belt conveyor system according to claim 6, characterized in that, The basic attribute parameters include the particle size distribution and bulk density of the actual material.

8. The dynamic simulation method for a flexible belt conveyor system according to claim 6, characterized in that, The measured and simulated property parameters include compacted density, natural angle of repose, angle of sliding friction, and angle of collapse.

9. The dynamic simulation method for a flexible belt conveyor system according to claim 1, characterized in that, The measured property parameters of the conveyor belt (12) include bandwidth, belt strength, belt weight, elastic modulus and hardness.

10. The dynamic simulation method for a flexible belt conveyor system according to claim 1, characterized in that, The simulation analysis of the flexible belt conveyor model under the no-load start-up operation mode is carried out to obtain the simulated values ​​of the preset index, specifically including the following steps: Step S311: Import the simulation model of the flexible belt conveyor into the simulation software, and set the material properties and boundary conditions of each component in the simulation model of the flexible belt conveyor. Step S312: Input the preset speed of the drive motor and start the simulation. After a preset time, determine whether the simulation result meets the convergence condition. If not, optimize the simulation model of the flexible belt conveyor and repeat steps S311-S312. If yes, obtain the simulated value of the preset index under the current working condition.

11. The dynamic simulation method for a flexible belt conveyor system according to claim 1, characterized in that, The simulation analysis of the flexible belt conveyor simulation model and the material particle simulation model under the load operation mode is carried out to obtain the simulated values ​​of the preset index, specifically including the following steps: Step S321: Import the 3D model of the conveyor belt and the simulation model of the material particles into the discrete element software, set the parameters of the 3D model of the conveyor belt and the simulation model of the material particles so that the material particle generation point is located above the material receiving point of the conveyor belt; import the simulation model of the flexible belt conveyor into the finite element software, and set the material properties and boundary conditions of each component in the simulation model of the flexible belt conveyor. A data transmission channel is established between the discrete element software and the finite element software by connecting them through a coupler. Step S322: Input the preset value of the material quantity into the discrete element software, input the preset speed of the drive motor into the finite element software, and control the discrete element software and the finite element software to start the simulation; Step S323: Within a preset time step, the discrete element software calculates the force data based on the current node data and transmits the force data to the finite element software. The finite element software calculates new node data based on the force data and transmits the new node data to the discrete element software. Step S324: After a preset time, determine whether the simulation results in the finite element software and discrete element software meet the convergence condition. If not, repeat steps S321-S323. If yes, obtain the simulated value of the preset index under the current working condition.

12. The dynamic simulation method for a flexible belt conveyor system according to claim 1, characterized in that, In the material start-up operation mode, simulation analysis is performed on the simulation model of the flexible belt conveyor and the simulation model of the material particles to obtain the simulated values ​​of the preset index. The specific steps include the following: Step S331: Import the 3D model of the conveyor belt and the simulation model of the material particles into the discrete element software, set the parameters of the 3D model of the conveyor belt and the simulation model of the material particles, and fill the material section of the conveyor belt with the material quantity preset value; import the simulation model of the flexible belt conveyor into the finite element software, and set the material properties and boundary conditions of each component in the simulation model of the flexible belt conveyor. A data transmission channel is established between the discrete element software and the finite element software by connecting them through a coupler. Step S332: Input the preset speed of the drive motor into the finite element software, and control the discrete element software and the finite element software to start the simulation; Step S333: Within a preset time step, the discrete element software calculates the force data based on the current node data and transmits the force data to the finite element software. The finite element software calculates new node data based on the force data and transmits the new node data to the discrete element software. Step S334: After a preset time, determine whether the simulation results in the finite element software and discrete element software meet the convergence condition. If not, repeat steps S331-S334; if yes, obtain the simulated value of the preset index under the current working condition.

13. The dynamic simulation method for a flexible belt conveyor system according to any one of claims 10-12, characterized in that, When the preset indicator is the power of the drive motor, obtaining the simulated value of the preset indicator under the current operating condition specifically includes the following steps: The driving force of the drive motor is obtained by searching in the search module, and the product of the driving force and the preset speed is the simulated power of the drive motor.

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