Material source stirring system for debris flow simulation test and parameter calculation method

Abstract

The invention discloses a material source stirring system for a debris flow simulation test and a parameter calculation method.The material source stirring system comprises a stirring cylinder, the interior of the stirring cylinder is rotationally connected with stirring blades through a stirring motor, a discharging opening is formed in the lower portion of the stirring cylinder, and a discharging valve is arranged at the discharging opening and used for adjusting the flow of flowing-out simulated debris flow; a flowing groove is formed below the discharge hole and is used for adjusting the angle of simulating debris flow release; according to the invention, related parameters of the material source stirring system are calculated according to related parameters of debris flow and debris flow simulation test requirements, the cost is reduced while the test requirements are met, and parameter calculation and design of the material source stirring system are carried out in combination with the flow and debris flow release angle of the debris flow test. The precision and the data repeatability of a debris flow simulation test are improved, and the reliability of the test is ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of debris flow prevention and control, and particularly relates to a source material stirring system for debris flow simulation experiments and a parameter calculation method thereof. Background Art

[0002] As a complex and highly destructive geological disaster, simulation experiments are a key means to study the impact force, failure mechanism, and disaster-causing laws of debris flows. To achieve high-precision and highly controllable debris flow simulation experiments, the key lies in the precise design of the experimental device and the scientific control of its parameters.

[0003] However, the existing debris flow experimental devices have certain limitations in structural design and performance regulation. In particular, in the calculation and optimization of key parameters such as the reasonable configuration of the motor power, the optimization of the thickness of the wear-resistant lining on the mixing drum wall, the precise control of the debris flow discharge, and the precise adjustment of the debris flow release angle, a systematic and accurate technical solution has not been formed. The existing technologies mostly rely on experience or simple calculation methods, and are unable to effectively cope with the complexity and dynamic changes of debris flow materials, resulting in insufficient control accuracy and low adjustment flexibility. These technical limitations directly restrict the accuracy of debris flow simulation experiments and the repeatability of data, and there is an urgent need to optimize the technical solution to comprehensively improve the overall performance of the debris flow source material stirring system and the reliability of the experiment. Summary of the Invention

[0004] The purpose of the present invention is to provide a source material stirring system for debris flow simulation experiments and a parameter calculation method thereof to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A parameter calculation method for a source material stirring system for debris flow simulation experiments, comprising the following steps:

[0006] S1: Selection of stirring motor; First, determine the viscosity μ and density ρ of the simulated debris flow material for the simulation experiment; calculate the output torque M of the stirring motor, M = C t ·μ·ρ·A b ·ω·R 2 ·N d ; calculate the motor power P, where C t is the torque coefficient, reflecting the influence of the shape of the stirring blade, the flow characteristics of the debris flow material, and the structure of the mixing drum, and can be determined according to the blade design standard and the material flow characteristics with reference to existing literature and industry standards, usually in the range of 0.5 to 0.8; μ is the viscosity of the debris flow material (Pa·s); ρ is the density of the debris flow material (kg / m 3 ); A b is the effective contact area of the stirring blade (m 2);R is the radius of the mixing drum (m); ω is the angular velocity of the mixing blades (rad / s); F is the power redundancy coefficient, which can be determined according to the basic principles of power redundancy calculation in the "Mechanical Design Handbook". In the design of mixing systems or high-viscosity fluid equipment, it usually ranges from 1.5 to 2.0 to ensure that the mixing system can cope with sudden resistance changes of debris flow materials; η is the total efficiency of the system, taking into account the efficiency losses of the motor and mechanical transmission, and can be set according to the efficiency parameters in the "Mechanical Design Handbook". For mixing systems with high loads and high-viscosity materials, the total efficiency of the system can be as low as 0.6 to 0.7; N d is the dynamic load correction coefficient, which can be determined through small-scale load fluctuation tests and ranges from 1.3 to 2 to compensate for the additional resistance generated by non-uniform flow during the mixing process;

[0007] S2: Design calculation of the wall thickness t of the mixing drum; The wall thickness t of the mixing drum includes the thickness t0 of the mixing drum shell and the thickness t of the wear-resistant lining layer provided inside the mixing drum shell to prevent the wear of the mixing drum shell c ; where, the wall thickness t of the mixing drum = t0 + t c ; Thickness of the wear-resistant lining layer In the formula, ρ is the density of debris flow materials (kg / m 3 ); g is the acceleration due to gravity, taking 9.8 m / s 2 ; h is the height of debris flow materials in the mixing drum (m); R is the radius of the mixing drum (m); M is the torque generated during the mixing process (N·m), which is the torque output by the motor calculated previously; k is the torque influence coefficient, reflecting the influence of the mixing torque on the additional stress of the cylinder wall. The optimal value of k can be obtained by numerically simulating the force condition of debris flow materials in the mixing drum, and the best value range is 0.7 to 1.0; σ f is the fatigue strength of the material (Pa), which can be determined according to the type of metal material used for the wear-resistant lining layer, referring to the material data in the Chinese national standard "GB / T 3077-2015 Alloy Structural Steel"; N s is the safety factor, which can be determined according to the standard of "GB / T16855 Mechanical Safety", and the value range is 1.5 to 2.0; N d is the dynamic load correction coefficient, which can be determined through small-scale load fluctuation tests and ranges from 1.3 to 2 to reflect the additional stress caused by vibration and load fluctuation during the mixing process;

[0008] S3: Calculation of simulated debris flow discharge; First, calculate the opening area A of the discharge port o , A o = L·W, then calculate the flow velocity v of the simulated debris flow, The simulated debris flow discharge Q = A o·v; where L is the opening length (m) of the discharge valve; W is the opening width (m) of the discharge valve; D is the equivalent diameter (m) of the opening of the discharge valve, g is the acceleration due to gravity, taking 9.8 m / s 2 ; h is the height (m) of the debris flow material in the mixing drum; μ is the viscosity (Pa·s) of the debris flow material; ρ is the density (kg / m 3 ); α is the turbulence correction coefficient, usually taking values between 0.85 and 0.95, used to correct the flow velocity change of the debris flow in the turbulent state. Debris flow with higher viscosity corresponds to a smaller correction coefficient, and debris flow with lower viscosity corresponds to a larger correction coefficient;

[0009] S4: Simulation of debris flow release angle control calculation; below the discharge outlet where the debris flow is simulated to flow out, a debris flow flow trench that rotates at an angle by pulling through a telescopic rod is set up to simulate the control of the debris flow release angle. The release angle of the simulated debris flow is adjusted by adjusting the length of the telescopic rod. The length S of the telescopic rod z is calculated by the formula , where θ is the debris flow release angle (°); S x is the length (m) representing the flow trench; S y is the vertical height (m) of the connection point of the threaded telescopic rod and the mixing drum; S z is the length (m) of the telescopic rod.

[0010] Preferably, in step S1, the angular velocity ω (rad / s) of the stirring blade is calculated from the stirring blade rotation speed N (RPM):

[0011] Preferably, in step S1, the dynamic load correction coefficient N d is determined through small-scale load experiments. A scaled-down source mixing system is manufactured for testing, and sensors are installed in the scaled-down source mixing system for monitoring. The maximum value P of the load fluctuation in each test is calculated max and the average value P avg The ratio is used, and the mean value of multiple groups of calculation results is used as the final dynamic load correction coefficient N d .

[0012] Preferably, in step S1, the torque influence coefficient k is determined through small-scale load experiments. A scaled-down source mixing system is manufactured, and according to the size parameters of the scaled-down source mixing system, the formula M = C t ·μ·ρ·A b ·ω·R 2 ·N d, select the appropriate motor torque for the small-scale load experiment. During the small-scale load experiment, install strain gauges on the wall of the mixing drum to measure the additional stress σ in real time j and record the statistics. Then, through the formula inversely deduce and fit the optimal torque influence coefficient k.

[0013] A source material mixing system for calculating parameters of a source material mixing system applicable to the above debris flow simulation experiment, including a mixing drum, a fixed seat, a mixing motor, mixing blades, a flow trench, and a telescopic rod. The mixing drum is fixedly connected to the fixed seat. The mixing motor is fixedly connected above the mixing drum. The mixing blades are vertically rotatably connected inside the mixing drum and the mixing blades are fixedly connected to the rotating shaft of the mixing motor. A discharge port is provided at the lower part of the mixing drum, and the discharge port is suspended from the fixed seat. A discharge valve is provided at the discharge port to control the opening and closing of the discharge port. The flow trench is arranged below the discharge port, and one end of the flow trench is rotatably connected to the fixed seat through a pin shaft. The other end of the flow trench is rotatably connected to one end of the telescopic rod through a pin shaft. The other end of the telescopic rod is rotatably connected to the outer wall of the mixing drum through a pin shaft;

[0014] Furthermore, a plurality of material bins are arranged on the outer side wall of the mixing drum, and a channel communicating with the inside of the material bin is arranged on the outer side wall of the mixing drum. A valve is arranged at the channel to control the opening and closing of the channel.

[0015] Setting the material bins facilitates adding materials for configuring the simulated debris flow into the mixing drum.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] 1. The present invention can calculate the corresponding motor power in combination with the actual flow characteristics of different test debris flow materials, so as to ensure the efficient operation of the system by adjusting the motor output power, and avoid uneven mixing caused by insufficient power or increased energy consumption caused by excessive power;

[0018] 2. Based on the stress analysis model designed for pressure vessels, the present invention combines the density of the debris flow material, the radius of the mixing drum, and the action of dynamic loads to accurately calculate and determine the thickness of the wear-resistant lining layer on the wall of the mixing drum. This method ensures that under the action of high load and long-term dynamic stress, the wear and replacement frequency of the main material of the mixing drum are reduced, the maintenance cost is lowered, and the service life is increased;

[0019] 3. The present invention accurately calculates and determines the flow rate and release angle of the simulated debris flow, ensuring that the release of the simulated debris flow during the simulation experiment conforms to the actual debris flow flow conditions, and improving the reliability of the debris flow simulation experiment results. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of the material source stirring system provided by an embodiment of the present invention;

[0021] In the figure, 1 - stirring cylinder, 2 - fixed seat, 3 - stirring motor, 4 - stirring blade, 5 - flow groove, 6 - telescopic rod, 11 - material bin. Specific embodiments

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0023] Please refer to Figure 1 , taking the Daleigou debris flow on the Mianjiu Expressway as the prototype of the debris flow model, the present invention provides a technical solution: a material source stirring system for debris flow simulation tests, including a stirring cylinder 1, a fixed seat 2, a stirring motor 3, stirring blades 4, a flow groove 5 and a telescopic rod 6; the stirring cylinder 1 is fixedly connected to the fixed seat 2, the stirring motor 3 is fixedly connected above the stirring cylinder 1, the stirring blades 4 are vertically rotatably connected inside the stirring cylinder 1 and the stirring blades 4 are fixedly connected to the rotating shaft of the stirring motor 3, a plurality of material bins 11 are arranged on the outer side wall of the stirring cylinder 1, and a channel communicating with the inside of the material bin 11 is arranged on the outer side wall of the stirring cylinder 1, and a valve is arranged at the channel to control the opening and closing of the channel; an outlet is arranged at the lower part of the stirring cylinder 1, and the outlet is suspended from the fixed seat, and a discharge valve is arranged at the outlet to control the opening and closing of the outlet, the flow groove 5 is arranged below the outlet and one end of the flow groove 5 is rotatably connected to the fixed seat 2 through a pin shaft, the other end of the flow groove 5 is rotatably connected to one end of the telescopic rod 6 through a pin shaft, and the other end of the telescopic rod 6 is rotatably connected to the outer wall of the stirring cylinder 1 through a pin shaft;

[0024] In this test, according to the laboratory site conditions, the accommodation requirements of the test materials and the mechanical manufacturing conditions, the radius R of the stirring cylinder 1 is set to 0.5 m, the height is set to 1 m, the thickness t0 of the shell of the stirring cylinder 1 is set to 0.01 m, and the effective contact area A of the stirring blades 4 b is designed to be 0.3 m 2 , the rotation speed N of the stirring blades 4 is set to 60 RPM, the opening width W of the discharge valve is designed to be 0.2 m, the length S of the flow groove x is designed to be 1 m, and the vertical height S of the connection point of the telescopic rod 6 and the stirring cylinder 1 y is designed to be 0.8 m. The geometric design parameters of the material source stirring system are shown in Table 1.

[0025] Table 1 Geometric design parameters of the material source stirring system

[0026]

[0027] The material parameters and release conditions of the simulated debris flow were determined by field measurements of the Daleigou debris flow. In this experiment, the viscosity of the simulated debris flow material was 0.063 Pa·s and the density was 1703 kg / m 3 The total amount of a single mixing is 0.6m 3 , combined with the mixing drum 1 radius R of 0.5m, the material height h = 0.77m; the simulated debris flow release angle θ in the test plan is 23.62°, and the simulated debris flow flow Q is controlled to 0.1m 3 / s, simulated debris flow test parameters, see Table 2.

[0028] Table 2 Parameters of the Daleigou debris flow simulation test

[0029]

[0030] Combined with the characteristics of the simulated debris flow materials and the relevant parameters of the mixing drum 1, the dynamic parameter design and calculation of the source mixing system are carried out to ensure that the source mixing system can process the material density ρ of 1703kg / m 3 , stability and reliability when simulating debris flow materials with a material viscosity μ of 0.063 Pa·s;

[0031] Parameter design:

[0032] Combined with the "Chemical Machinery Handbook", the torque coefficient C of the stirring blade 4 is t Recommended value (usually 0.5-0.8), blade design standards, test debris flow material characteristics and power and efficiency balance requirements, torque coefficient C t Set to 0.7 to achieve efficient mixing and uniform distribution of materials at a stirring blade 4 speed N of 60 RPM;

[0033] According to the basic principles of power redundancy calculation and efficiency parameters in the Mechanical Design Manual, the power redundancy coefficient F is set to 2 and the total system efficiency η is set to 0.7 to ensure that the source mixing system can cope with the sudden resistance changes of the test debris flow materials and achieve effective energy utilization; according to the GB / T 16855 Machinery Safety standard, the safety factor N s It is set to 1.8 to ensure the safety margin of the equipment under high load environment; in terms of material selection, the mixing drum 1, wear-resistant lining and mixing blade 4 are all made of high-strength carbon steel, and its material fatigue strength σ f According to the material data in the GB / T 3077-2015 Alloy Structural Steel standard, the 8 Pa; the gravitational acceleration g is taken as the standard value 9.8m / s 2, ensure that all mechanical calculations comply with the actual environmental conditions; the performance and safety design parameters of the material source stirring system are shown in Table 3.

[0034] Table 3 Performance and Safety Design Parameters of the Material Source Stirring System

[0035]

[0036] Parameter calculation:

[0037] Selection of the stirring motor 3; calculate the angular velocity of the stirring blade Substitute the data to obtain ω = 6.2832 rad / s; power of the stirring motor 3 Among them, the output torque M of the stirring motor 3 = C t ·μ·ρ·A b ·ω·R 2 ·N d , substitute the data to obtain the power P of the stirring motor 3 = 908.779 W;

[0038] Determine the dynamic load correction factor N through small-scale load fluctuation tests d and the torque influence coefficient k:

[0039] In this embodiment, the material source stirring system adopts a scale ratio of 1:10, and the simulated debris flow material density ρ is 1703 kg / m 3 , the material viscosity μ is 0.063 Pa·s, and the rotation speed N of the stirring blade 4 is set to 60 RPM. First, the load change of the stirring tank is monitored in real time through sensors, especially in the case of uneven material flow, record the amplitude and frequency of the load fluctuation, and then calculate the maximum value P of the load fluctuation in each test according to the test data under multiple sets of the same test conditions max and the average value P avg ratio, and use the mean value of the calculated results as the final dynamic load correction factor N d , determine N d to be 1.5, which effectively compensates for the additional resistance and stress fluctuations caused by uneven material flow, ensuring that the stirring system can operate smoothly under complex flow conditions. The load fluctuation monitoring results are shown in Table 4 below:

[0040] Table 4 Maximum and Average Values of Load Fluctuation Tests

[0041] Test Number <![CDATA[P max (N)]]> <![CDATA[P avg (N)]]> <![CDATA[N d > Test 1 25.0 16.0 1.56 Test 2 23.5 15.7 1.50 Test 3 24.0 16.2 1.48 Test 4 26.0 17.4 1.49 Test 5 24.5 16.5 1.48

[0042] Measure the additional stress σ in real time through the strain gauges set on the stirring tank wall j and record the statistics, and then through the formula Take the approximate values of multiple sets of data, and thus inversely deduce and fit the optimal torque influence coefficient k = 0.85. The strain gauge measurement data are shown in Table 5 below:

[0043] Table 5 Additional Stress Monitoring during Load Fluctuation Test

[0044]

[0045] Since the debris flow material is a low-viscosity dilute material, the turbulence effect is relatively slight. Due to the strong fluidity of the low-viscosity debris flow material and the relatively light turbulence effect, the required correction is small. To avoid excessive correction, the turbulence correction coefficient is generally set to 0.9 to correct the influence of the viscosity characteristics of the debris flow material used in the test on the flow velocity and ensure accurate flow control at the discharge valve opening width (0.2 m). The dynamic control parameters of the material source stirring system are shown in Table 6.

[0046] Table 6 Dynamic Control Parameters of the Material Source Stirring System

[0047]

[0048] To ensure that the debris flow material in the debris flow simulation test is under high load and long-term dynamic stress, reduce the wear and replacement frequency of the stirring cylinder shell material, lower the maintenance cost and increase the service life, a wear-resistant lining is fixed inside the stirring cylinder shell by buckles, and the parameters of the wear-resistant lining are designed and calculated. The thickness of the wear-resistant lining Substitute the data to obtain the thickness t of the wear-resistant lining c = 0.07 mm, and the thickness of the stirring cylinder t = t0 + t c = 10.07 mm;

[0049] During the specific debris flow simulation test, it is necessary to adjust the flow rate Q and release angle θ of the simulated debris flow to conform to the actual debris flow flow situation in Daleigou. Among them, the flow rate Q of the simulated debris flow is adjusted through the discharge valve. In this test, the opening width W of the discharge valve is designed to be 0.2 m. Therefore, the control of the flow rate Q of the simulated debris flow only needs to adjust the opening length L of the discharge valve. Through the formula, It is calculated that the opening length of the discharge valve is L = 0.143 m and the corresponding equivalent diameter D of the discharge valve opening is 0.167 m;

[0050] The release angle θ of the simulated debris flow is adjusted by adjusting the length S of the telescopic rod z , thereby adjusting the rotation amplitude of the flow channel to adjust the release angle θ of the simulated debris flow. The length S of the telescopic rod z is calculated through the formula , where θ is the debris flow release angle; S x represents the length of the flow channel; S y is the vertical height of the connection point of the telescopic rod and the stirring cylinder; S z is the length of the telescopic rod, and S z= 1.5061 m; The calculation results of the dynamic parameters of the material source mixing system are shown in Table 7

[0051] Table 7 Calculation Results of Parameter Control

[0052]

[0053] After all the parameter calculations of the material source mixing system are designed and installed, the mixing motor can be started to mix the simulated debris flow, and the opening length L of the discharge valve and the length S of the telescopic rod in the calculation structure can be adjusted accordingly to start the debris flow simulation test. z to carry out corresponding adjustments and start the debris flow simulation test.

[0054] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for calculating parameters of a material source stirring system for debris flow simulation tests, characterized in that, It includes the following steps: S1: Selection of stirring motor; First, determine the viscosity μ and density ρ of the simulated debris flow material for the simulation experiment; Calculate the output torque M of the stirring motor, M = C t ·μ·ρ·A b ·ω·R 2 ·N d ; Calculate the motor power P, where C t is the torque coefficient; μ is the viscosity of debris flow material; ρ is the density of debris flow material; A b is the effective contact area of the stirring blade; R is the radius of the mixing drum; ω is the angular velocity of the stirring blade; F is the power redundancy coefficient; η is the total efficiency of the system; N d is the dynamic load correction coefficient; S2: Design calculation of the wall thickness t of the mixing drum; the wall thickness t of the mixing drum includes the thickness t0 of the mixing drum shell and the thickness t of the wear-resistant lining layer provided in the mixing drum shell to prevent the wear of the mixing drum shell c ; among them, the wall thickness t of the mixing drum = t0 + t c ; thickness of the wear-resistant lining layer In the formula, ρ is the density of debris flow materials; g is the acceleration of gravity; h is the height of debris flow materials in the mixing drum; R is the radius of the mixing drum; M is the output torque of the mixing motor; k is the torque influence coefficient; σ f is the fatigue strength of the material; N s is the safety factor; N d is the dynamic load correction factor; S3: Simulate debris flow discharge calculation; First, calculate the opening area A of the discharge port o , A o = L·W, then calculate the flow velocity v of the simulated debris flow, The simulated debris flow discharge Q = A o ·v; In the formula, L is the opening length of the discharge valve; W is the opening width of the discharge valve; D is the equivalent diameter of the discharge valve opening, g is the acceleration due to gravity; h is the height of the debris flow material in the mixing drum; μ is the viscosity of the debris flow material; ρ is the density of the debris flow material; α is the turbulence correction coefficient; S4: Simulation debris flow release angle control calculation; A debris flow flow trench that rotates at an angle by being pulled by a telescopic rod is arranged below the discharge port where the simulated debris flow flows out to control the simulated debris flow release angle. The simulated debris flow release angle is adjusted by adjusting the length of the telescopic rod, and the length of the telescopic rod is S z Through the formula Calculate, where θ is the debris flow release angle; S x Represents the length of the flow trench; S y Is the vertical height of the connection point between the telescopic rod and the mixing drum; S z Is the length of the telescopic rod.

2. The method for calculating the parameters of the material source stirring system for debris flow simulation tests according to claim 1, characterized in that, In step S1, the angular velocity ω of the stirring blade is calculated from the rotational speed N of the stirring blade as follows:

3. The method for calculating the parameters of the material source stirring system in the debris flow simulation test according to claim 1, characterized in that In step S1, the dynamic load correction factor N d is determined through small-scale load experiments. A scaled-down material source stirring system is manufactured for testing, and sensors are installed in the scaled-down material source stirring system for monitoring. The maximum value P of the load fluctuation in each test is calculated max and the average value P avg are used to calculate the ratio. The mean value of multiple groups of calculation results is used as the final dynamic load correction factor N d .

4. The method for calculating the parameters of the material source stirring system in the debris flow simulation test according to claim 1, characterized in that, In step S1, the torque influence coefficient k is determined through a small-scale load experiment. By manufacturing a scaled-down material source stirring system and using the dimensional parameters of the scaled-down material source stirring system in the formula M = C t ·μ·ρ·A b ·ω·R 2 ·N d , the motor torque for the appropriate small-scale load experiment is selected. During the small-scale load experiment, the additional stress σ is measured in real time by installing strain gauges on the stirring drum wall j and recorded and statistically analyzed. Then, the optimal torque influence coefficient k is inversely deduced and fitted through the formula ​ 5. A material source stirring system for a calculation method of parameters of a material source stirring system applicable to the debris flow simulation test according to any one of claims 1-4, characterized in that: It includes a mixing drum, a fixed seat, a mixing motor, mixing blades, a flow groove and a telescopic rod. The mixing drum is fixedly connected to the fixed seat. The mixing motor is fixedly connected above the mixing drum. The mixing blades are vertically rotatably connected inside the mixing drum and the mixing blades are fixedly connected to the rotating shaft of the mixing motor. A discharge port is provided at the lower part of the mixing drum, and the discharge port is suspended from the fixed seat. A discharge valve is provided at the discharge port to control the opening and closing of the discharge port. The flow groove is provided below the discharge port, and one end of the flow groove is rotatably connected to the fixed seat through a pin shaft. The other end of the flow groove is rotatably connected to one end of the telescopic rod through a pin shaft. The other end of the telescopic rod is rotatably connected to the outer wall of the mixing drum through a pin shaft.

6. The provenance stirring system according to claim 5, characterized in that: A plurality of material bins are provided on the outer side wall of the mixing drum, and a channel communicating with the inside of the material bin is provided on the outer side wall of the mixing drum. A valve is provided at the channel to control the opening and closing of the channel.

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