Rheometric test rotor capable of eliminating end effects

Abstract

The utility model discloses a rheological test rotor that can eliminate end effect, which comprises an upper rotor, an intermediate rotor and a lower rotor. The upper rotor, the intermediate rotor and the lower rotor are fixedly connected with a motor in sequence along the axial direction, forming a layered rotor structure. The intermediate rotor is located between the upper rotor and the lower rotor, and the three rotate synchronously without relative displacement between the rotors, so that there is no flow field fluctuation when the material flows between adjacent rotors. A torque sensor is installed on the shaft of the intermediate rotor. The rheological test rotor can be used in an upright or inverted manner. The utility model is suitable for rotary rheometers and other equipment, effectively overcomes the data error caused by end effect, and significantly improves the accuracy of rheological data.

Description

Technical Field

[0001] This utility model belongs to the technical field of rheological testing devices, and in particular, relates to a rheological testing rotor that can eliminate end effects. Background Technology

[0002] The core principle of rheometers using a concentric cylindrical structure (Couette structure) is to construct a controllable shear field, measure the mechanical response of a fluid under shear stress, and then deduce its rheological properties, such as viscosity and elasticity. This structure, because it provides a relatively uniform shear environment, is widely used for the rheological analysis of low-viscosity fluids. When one of the cylinders rotates, the fluid within the gap is "driven" by viscosity, forming shear flow, i.e., relative sliding occurs between fluid layers, resulting in shear deformation. By controlling the rotational speed (shear rate) and measuring the required torque (corresponding to shear stress), the rheological relationship of the fluid can be established.

[0003] Currently, when rheometers employ a concentric cylindrical structure for testing, the errors caused by the end effect of the material during the testing process cannot be effectively resolved, thus affecting the accuracy of actual measurements. Specifically, for rheometers with a concentric cylindrical structure, the end effect is caused by two factors: firstly, the viscous effect of the sample between the rotating cylinder (usually the inner cylinder) and the bottom end face of the fixed cylinder; and secondly, the uneven flow of the sample near the end of the side gap between the rotating and fixed cylinders.

[0004] A patent with publication number CN103822852A discloses a method and apparatus for testing vertical superimposed oscillatory rheological flow at high shear rates. In this method, material in a barrel, under the pressure of a plunger, passes through an annular slit die, forming a high-shear-rate mainstream flow field. The shear stress and shear rate of the mainstream flow field are calculated based on the plunger velocity, pressure gradient of the fully developed flow region, die shape, and plunger interface dimensions. The oscillating motion of the die core rotor drives the material between the die slits to generate a vertically superimposed oscillatory flow field. Based on the torque and oscillation frequency of the die core rotor, and the dimensions of the barrel and die core rotor, the shear stress, shear strain, and shear rate of the superimposed oscillatory flow field are calculated, and various material functions can be further calculated. A heating device is installed on the barrel to ensure a constant temperature of the material flow during the experiment. This patent uses a two-lobed rotor to avoid edge effects, resulting in high processing difficulty, high cost, and assembly difficulties, and it does not consider application in rotational rheometers. Utility Model Content

[0005] This invention addresses the problem that existing rheometers, which use a concentric cylindrical structure for testing, cannot effectively solve the error caused by the end effect of materials during the testing process, thus affecting the accuracy of actual measurements. The invention proposes a rheological testing rotor that can eliminate the end effect.

[0006] A rheological testing rotor capable of eliminating end effects includes an upper rotor, an intermediate rotor, and a lower rotor. The upper rotor, intermediate rotor, and lower rotor are sequentially fixedly connected to a motor along the axial direction, forming a layered rotor structure. The intermediate rotor is located between the upper rotor and the lower rotor. All three rotors rotate synchronously without relative displacement between them, ensuring no flow field fluctuations when materials flow between adjacent rotors. A torque sensor is installed on the shaft of the intermediate rotor. The rheological testing rotor can be used upright or inverted.

[0007] Furthermore, it also includes three independent shaft systems. The upper rotor, middle rotor and lower rotor are respectively connected to the motor through corresponding independent shaft systems to achieve synchronous rotation at the same speed.

[0008] Furthermore, the centerlines of the upper rotor, the middle rotor, and the lower rotor coincide to ensure their coaxiality and avoid the influence of angular deviation on the test results.

[0009] Furthermore, gaps are provided between the upper rotor and the intermediate rotor, and between the intermediate rotor and the lower rotor. The dimensions of these gaps are controlled within a small range to prevent material from entering the gaps without affecting the independent rotation of each rotor.

[0010] Furthermore, the gaps between the upper rotor and the middle rotor, as well as between the middle rotor and the lower rotor, are all less than 0.1 mm.

[0011] Furthermore, one end of the torque sensor is connected to the intermediate rotor, and the other end is connected to the output shaft of the motor, for measuring the torque between the intermediate rotor and the motor.

[0012] Furthermore, when the rheological test rotor is used in the upright position, it is adapted to the plunger and barrel structure of the capillary rheometer. The barrel is equipped with a pressure sensor and a temperature sensor to form an orthogonal superimposed flow field to realize dynamic rheological testing.

[0013] Furthermore, the barrel is equipped with a heating device to achieve constant temperature control.

[0014] Furthermore, the rotational speeds of the upper rotor, the middle rotor, and the lower rotor are all controllable, and they support uniform speed or sinusoidal oscillation modes.

[0015] Furthermore, when the rheological test rotor is used in reverse, it is adapted to the concentric cylindrical structure of the rotating rheometer to eliminate the end effect between the rotating cylinder and the fixed cylinder.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0017] 1. This utility model's rheological rotor consists of an upper rotor, a middle rotor, and a lower rotor. These three rotors rotate synchronously at the same speed via independent shaft systems, ensuring no relative displacement and avoiding flow field disturbances. Effective torque is directly measured via a torque sensor mounted on the middle rotor, eliminating the need for end-point calibration. Minimizing the gap between adjacent rotors and strictly controlling coaxiality effectively prevents material interference and angular deviations from affecting the test results, effectively solving the errors caused by end-point effects during measurement and compensating for the measurement deficiencies of traditional rheometers.

[0018] 2. The rotor structure of this invention can be used upright or upside down, and is suitable for equipment such as rotational rheometers, significantly improving the accuracy of rheological data. At the same time, the rotor structure is easy to process and assemble, resulting in low manufacturing costs. Attached Figure Description

[0019] Figure 1 This is a cross-sectional structural diagram of the present invention;

[0020] Figure 2 This is a schematic diagram illustrating the orthogonal superposition rheological testing of samples using this utility model in an upright position.

[0021] Figure 3 This is a schematic diagram of the concentric cylindrical structure of the present invention and the rotational rheometer when used upside down.

[0022] In the above figure, 1. Upper rotor; 2. Middle rotor; 3. Lower rotor; 4. Motor; 5. Plunger; 6. Barrel; 7. Rheological measurement flow field; 9. Rheological testing rotor; 10. Pressure sensor; 11. Temperature sensor; 12. Torque sensor; 13. Rotor gap; 14. Fixed cylinder. Detailed Implementation

[0023] To clearly illustrate the technical features of this utility model, the following detailed description is provided through specific embodiments and in conjunction with the accompanying drawings.

[0024] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0025] Furthermore, in the description of this utility model, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0026] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0027] In this utility model, unless otherwise expressly specified and limited, the first feature "on" or "below" the second feature may be in direct contact with the first and second features, or indirect contact through an intermediate medium. In the description of this specification, references to terms such as "an embodiment," "some embodiments," "example," "specific example," or "some examples" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0028] Example 1

[0029] like Figure 1As shown, a rheological testing rotor that can eliminate end effects includes an upper rotor 1, an intermediate rotor 2, and a lower rotor 3. The upper rotor 1, intermediate rotor 2, and lower rotor 3 are sequentially fixedly connected to a motor 4 along the axial direction, forming a layered rotor structure. The intermediate rotor 2 is located between the upper rotor 1 and the lower rotor 3. The three rotors rotate synchronously and there is no relative displacement between them, so that there is no flow field fluctuation when the material flows between adjacent rotors. A torque sensor 12 is installed on the shaft of the intermediate rotor 2. The rheological testing rotor 9 can be used upright or inverted.

[0030] In this embodiment, the rheological testing rotor 9 consists of an upper rotor 1, a middle rotor 2, and a lower rotor 3, which are sequentially fixedly connected to a motor 4. The rheological testing rotor 9 also includes three independent shaft systems. The upper rotor 1, the middle rotor 2, and the lower rotor 3 are each connected to the motor 4 through their respective independent shaft systems to achieve synchronous rotation at the same speed. The centerlines of the upper rotor 1, the middle rotor 2, and the lower rotor 3 coincide to ensure their coaxiality and avoid the influence of angular deviations on the test results.

[0031] There are gaps between the upper rotor 1 and the intermediate rotor 2, and between the intermediate rotor 2 and the lower rotor 3. The size of these gaps is controlled within a small range. Without affecting the independent rotation of each rotor, this effectively prevents material from entering the gaps and causing unnecessary measurement errors. Specifically, the gaps between the upper rotor 1 and the intermediate rotor 2, and between the intermediate rotor 2 and the lower rotor 3, are all less than 0.1 mm.

[0032] Example 2

[0033] like Figure 1 As shown, a rheological testing rotor that can eliminate end effects includes an upper rotor 1, an intermediate rotor 2, and a lower rotor 3. The upper rotor 1, intermediate rotor 2, and lower rotor 3 are sequentially fixedly connected to a motor 4 along the axial direction, forming a layered rotor structure. The intermediate rotor 2 is located between the upper rotor 1 and the lower rotor 3. The three rotors rotate synchronously and there is no relative displacement between them, so that there is no flow field fluctuation when the material flows between adjacent rotors. A torque sensor 12 is installed on the shaft of the intermediate rotor 2. The rheological testing rotor 9 can be used upright or inverted.

[0034] In this embodiment, as Figure 2 When the rotor for rheological testing is used in an upright position, it works in conjunction with the plunger 5 and barrel 6 of the capillary rheometer to achieve orthogonal superposition rheological testing of the samples.

[0035] Specifically, the system includes a rheological testing rotor 9, composed of an upper rotor 1, an intermediate rotor 2, and a lower rotor 3, a plunger 5, a barrel 6, a motor 4, and a torque sensor 12. The upper rotor 1, intermediate rotor 2, and lower rotor 3 rotate synchronously at the same speed, with no relative displacement between them, ensuring no flow field fluctuations when the material flows between adjacent rotors. One end of the torque sensor 12 is connected to the intermediate rotor 2, and the other end is connected to the output shaft of the motor 4, thereby measuring the torque between the motor output shaft and the intermediate rotor 2. By measuring the torque of the intermediate rotor 2 through the torque sensor 12, while ignoring the torque values ​​of the upper rotor 1 and lower rotor 3, data errors caused by end-effects can be effectively eliminated. Pressure is applied to the material in the barrel 6 by the plunger 5, causing the material to form a downward main flow field and orthogonally superimposed flow fields as it passes through the rheological rotor 9. A heating device and a temperature sensor 11 on the barrel are used to maintain a constant temperature for the material 7.

[0036] When the rheological testing rotor is used in its upright position, its working process is as follows:

[0037] Step 1: Turn on the temperature heating device and use the temperature sensor 11 to monitor the temperature inside the material cylinder 6 in real time. After the temperature inside the material cylinder 6 reaches the set value, add the material 7 into the material cylinder 6 and wait for the temperature of the material 7 to rise to the set temperature.

[0038] Step 2: Start the motor control system of plunger 5, so that the motor runs at a preset speed. The plunger 5 driven by motor 4 pushes the material 7 to move at a specified speed (various speeds such as uniform speed or sinusoidal oscillation can be set), thereby forming a high shear rate mainstream field.

[0039] Step 3: Start the motor control system of the rheological rotor 9 to make the motor 4 rotate at the set speed (uniform speed or sinusoidal oscillation, etc.) to ensure that the three rotors move synchronously at the same speed. This can avoid interference with the measurement results of shear stress and shear rate when the material passes through the rheological measurement flow field.

[0040] Step 4: After both motor systems have reached a stable state, when material 6 passes through the barrel 7, pressure sensor 10 is used to measure the pressure, and torque sensor 12 is used to measure the torque of the intermediate rotor. All measurement data are recorded.

[0041] Step 5: After the experiment, turn off the temperature heating device, the plunger motor control system and the rheostat rotor motor control system in sequence, remove the plunger 5, clean the material residue in the barrel 6, clean the barrel and organize the relevant equipment.

[0042] Step Six: Based on the recorded measurement data and the inherent dimensional parameters of the measuring device, organize and calculate the shear stress and shear rate to finally obtain the material function.

[0043] Example 3

[0044] like Figure 1 As shown, a rheological testing rotor that can eliminate end effects includes an upper rotor 1, an intermediate rotor 2, and a lower rotor 3. The upper rotor 1, intermediate rotor 2, and lower rotor 3 are sequentially fixedly connected to a motor 4 along the axial direction, forming a layered rotor structure. The intermediate rotor 2 is located between the upper rotor 1 and the lower rotor 3. The three rotors rotate synchronously and there is no relative displacement between them, so that there is no flow field fluctuation when the material flows between adjacent rotors. A torque sensor 12 is installed on the shaft of the intermediate rotor 2. The rheological testing rotor 9 can be used upright or inverted.

[0045] This embodiment is for a rheological test rotor inverted application scenario, adapted to the concentric cylindrical structure of a rotating rheometer, to eliminate the end effect in traditional concentric cylindrical testing.

[0046] In this embodiment, the testing device includes an inverted rheological rotor (upper rotor 1, middle rotor 2, and lower rotor 3), a fixed cylinder 14 for the rotational rheometer, a motor 4, and a torque sensor 12. The three rotors rotate synchronously at the same speed with minimal gaps and maintain coaxiality. After inversion, a rheological measurement flow field 8 is formed between the rheological testing rotor 9, the fixed cylinder 14, and the material 7, which can eliminate the viscous effect at the bottom of the rotating cylinder and the fixed cylinder 14, as well as the end effect caused by uneven material flow at the end of the side gaps.

[0047] Based on the rotor speed and the measured torque, values ​​of shear stress, shear strain, and shear rate can be obtained. Further calculations can yield rheological parameters such as viscosity, storage modulus, dissipation modulus, and loss factor. This eliminates the end-effector effect caused by the viscous adhesion between the sample and the bottom end face of the fixed cylinder, as well as the end-effector effect caused by uneven flow near the end of the sample in the side gap between the rotating and fixed cylinders.

[0048] Obviously, the above-described embodiments are merely examples for clearly illustrating the present invention and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A rheological test rotor capable of eliminating end effects, characterized in that, It includes an upper rotor, an intermediate rotor, and a lower rotor. The upper rotor, intermediate rotor, and lower rotor are sequentially fixedly connected to the motor along the axial direction to form a layered rotor structure. The intermediate rotor is located between the upper rotor and the lower rotor. The three rotors rotate synchronously and there is no relative displacement between the rotors, so that there is no flow field fluctuation when the material flows between adjacent rotors. A torque sensor is installed on the shaft of the intermediate rotor. The rheological test rotor can be used upright or inverted.

2. The rheological test rotor capable of eliminating end effects according to claim 1, characterized in that, It also includes three independent shaft systems. The upper rotor, middle rotor and lower rotor are respectively connected to the motor through the corresponding independent shaft systems to achieve synchronous rotation at the same speed.

3. A rheological test rotor capable of eliminating end effects according to claim 1, characterized in that, The centerlines of the upper rotor, the middle rotor, and the lower rotor coincide.

4. A rheological test rotor capable of eliminating end effects according to claim 1, characterized in that, There are gaps between the upper rotor and the middle rotor, and between the middle rotor and the lower rotor.

5. A rheological test rotor capable of eliminating end effects according to claim 4, characterized in that, The gaps between the upper rotor and the middle rotor, as well as between the middle rotor and the lower rotor, are all less than 0.1 mm.

6. A rheological test rotor capable of eliminating end effects according to claim 1, characterized in that, One end of the torque sensor is connected to the intermediate rotor, and the other end is connected to the output shaft of the motor, used to measure the torque between the intermediate rotor and the motor.

7. A rheological test rotor capable of eliminating end effects according to claim 1, characterized in that, When the rheological test rotor is used upright, it is adapted to the plunger and barrel structure of the capillary rheometer. The barrel is equipped with a pressure sensor and a temperature sensor to form an orthogonal superimposed flow field to achieve dynamic rheological testing under high shear rate.

8. A rheological test rotor capable of eliminating end effects according to claim 7, characterized in that, The barrel is equipped with a heating device to achieve constant temperature control.

9. A rheological test rotor capable of eliminating end effects according to claim 1, characterized in that, The rotational speeds of the upper rotor, middle rotor, and lower rotor are all controllable, and they support uniform speed or sinusoidal oscillation modes.

10. A rheological test rotor capable of eliminating end effects according to claim 1, characterized in that, When the rheological test rotor is used in reverse, it is adapted to the concentric cylindrical structure of the rotational rheometer to eliminate the end effect between the rotating cylinder and the stationary cylinder.

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