A multifunctional rheological testing device

Abstract

The utility model discloses a multifunctional rheological testing device, including U type material cylinder, plunger and rotor subassembly, U type material cylinder includes two vertical sections and the curved section of connecting two vertical sections, plunger is adapted with the vertical section of U type material cylinder and can move along the vertical section inner wall of U type material cylinder axial movement, is used for extruding the material in this vertical section, rotor subassembly sets up in another vertical section of U type material cylinder, and rotor subassembly includes the main rotor of the intermediate position and first auxiliary rotor and second auxiliary rotor respectively located main rotor upper and lower both ends, main rotor, first auxiliary rotor and second auxiliary rotor and the vertical section inner wall of U type material cylinder form annular slit type die mouth, and material can flow through the annular slit under the extrusion of plunger, the utility model solves the problem of traditional rheological test in loading and unloading sample time -consuming, edge effect is serious, and the single measurement mode, the viscoelasticity test difficult problem under high shear rate.

Description

Technical Field

[0001] This utility model belongs to the field of rheological testing technology, and in particular, relates to a multifunctional rheological testing device. Background Technology

[0002] The core of a rheometer is to apply stress or strain to a sample in a controlled manner, while accurately measuring the sample's response (such as the generated strain or stress), and then analyzing the material's rheological parameters using a rheological model. Traditional rheometers cannot effectively suppress edge effects. At the edges of the test flow field, samples with different stress-strain histories exist, resulting in an incompletely developed flow field and introducing significant errors into the test results. In practical applications, polymer processing often requires dynamic viscoelastic parameters at high shear rates, and existing equipment struggles to effectively superimpose high shear rates with vertical oscillating fields. Traditional rheometers are time-consuming and complex to load and unload, especially capillary rheometers, where samples must be reloaded after extrusion, wasting manpower and resources.

[0003] A patent application with publication number CN103134741A discloses a linear vibration annular gap extrusion rheometer, comprising: a barrel with a central through-hole, an extrusion plunger rod sliding within the barrel, a central rod coaxially mounted within the barrel, a pressure sensor and a temperature sensor extending into the barrel, and a heater / cooler installed around the barrel. Its key feature is that the annular gap between the central rod and the barrel forms a test chamber; the test sample, which can flow within the barrel, flows out of the test chamber under the extrusion action of the plunger rod; and the central rod vibrates linearly along its centerline as the test sample flows within the test chamber. This patent is a parallel superposition rheological testing device, significantly different from vertical superposition. For fluids requiring consideration of volume compression effects, the control and calculation of the parallel superposition flow field are more difficult; moreover, the structure of this patent is similar to that of a traditional capillary rheometer, making material loading and unloading very cumbersome. Utility Model Content

[0004] This invention addresses the limitations of existing rheometers in effectively suppressing edge effects. At the edges of the test flow field, samples with varying stress-strain histories exist, resulting in an incompletely developed flow field and significant errors in the test results. In practical applications, polymer processing often requires dynamic viscoelastic parameters at high shear rates, which existing equipment struggles to effectively superimpose with vertical oscillatory fields. Traditional rheometers are time-consuming and complex to load and unload, especially capillary rheometers, where sample reloading is necessary after extrusion, leading to wasted manpower and resources. Therefore, a multifunctional rheological testing device is proposed.

[0005] A multifunctional rheological testing device includes a U-shaped barrel, a plunger, and a rotor assembly. The U-shaped barrel includes two vertical sections and a curved section connecting the two vertical sections. The plunger is adapted to the vertical section of the U-shaped barrel and can move axially along the inner wall of the vertical section of the U-shaped barrel to compress the material within the vertical section. The rotor assembly is disposed in another vertical section of the U-shaped barrel and includes a main rotor located in the middle and a first auxiliary rotor and a second auxiliary rotor located at the upper and lower ends of the main rotor, respectively. The main rotor, the first auxiliary rotor, and the second auxiliary rotor form an annular gap with the inner wall of the vertical section of the U-shaped barrel, and the material can flow through the annular gap under the compression of the plunger.

[0006] Furthermore, a heating device and a temperature sensor are installed on the U-shaped barrel. The temperature sensor measures the real-time temperature inside the barrel and performs closed-loop control to keep the material at a constant temperature during the testing process.

[0007] Furthermore, the temperature sensor is installed on the wall of the U-shaped cylinder, and the detection end of the temperature sensor directly contacts the material inside the U-shaped cylinder to detect the temperature of the material.

[0008] Furthermore, the radial width of the circumferential gap formed between the inner wall of the U-shaped barrel and the rotor assembly is 0.1 to 2 mm.

[0009] Furthermore, a gap is provided between the main rotor and the first auxiliary rotor and the second auxiliary rotor, and the width of the gap is less than 0.1 mm, so that no material flows into the gap.

[0010] Furthermore, the annular gap region formed by the main rotor and the U-shaped barrel is a fully developed flow region, while the annular gap region formed by the first auxiliary rotor, the second auxiliary rotor, and the U-shaped barrel is a partially developed flow region. Pressure sensors for testing pressure gradients are provided at both ends of the fully developed flow region.

[0011] Furthermore, at least two pressure sensors are provided, and the detection ends of the pressure sensors are respectively placed at both ends of the fully developed flow zone of the annular gap.

[0012] Furthermore, the main rotor's shaft is arranged along the axial center of the main rotor, with one end of the main rotor shaft fixedly connected to the main rotor and the other end extending out of the U-shaped material cylinder and connected to the motor that drives the rotor and the circumferential torque testing system.

[0013] Furthermore, the outer wall of the plunger is sealed to the inner wall of the U-shaped cylinder, and the end of the plunger away from the material is connected to the plunger driving device, which can drive the plunger to make linear reciprocating motion along the axial direction of the U-shaped cylinder.

[0014] Furthermore, the axes of the main rotor, the first auxiliary rotor, and the second auxiliary rotor are parallel.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0016] 1. This utility model includes a U-shaped material cylinder, a plunger, and a rotor assembly. The rotor assembly includes a main rotor located in the middle and a first auxiliary rotor and a second auxiliary rotor located at the upper and lower ends of the main rotor, respectively. An annular gap is formed between the main rotor, the first auxiliary rotor, and the second auxiliary rotor and the inner wall of the vertical section of the U-shaped material cylinder. The plunger compresses the material to form an axial shear flow field, while the rotor assembly drives the material to rotate circumferentially, forming an orthogonally superimposed flow field. The rotor assembly can eliminate edge effects and ensure the accuracy of parameter measurements in the fully developed flow region.

[0017] 2. After the plunger descends and squeezes the liquid to complete the test, it returns to its initial position, and the liquid level also returns to its initial position, allowing for repeated testing. This significantly reduces the workload of loading and unloading samples. It can be widely applied to rheological measurements in polymer solutions, inks, coatings, and other fields, providing an efficient solution for accurate rheological testing under complex flow fields. It also boasts high applicability, supporting multiple test modes such as pure shear, pure oscillation, and their superposition, enabling dynamic viscoelastic testing of samples at high shear rates. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of this utility model;

[0019] Figure 2 This is a schematic diagram of the structure of Embodiment 1 of the present utility model;

[0020] Figure 3 This is a schematic diagram of the structure of the present invention when a constant pressure type driving plunger is used.

[0021] In the diagram, 1. Piston; 2. U-shaped barrel; 3. Material; 4. Second auxiliary rotor; 5. Circular slit die; 6. Main rotor; 7. Temperature sensor; 8. Fully developed flow zone; 9. Main and auxiliary rotor gap; 10. First auxiliary rotor; 11. Main rotor shaft; 12. Pressure sensor; 13. Torque sensor. Detailed Implementation

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] Example 1

[0028] like Figure 1As shown, a multifunctional rheological testing device includes a U-shaped cylinder 2, a plunger 1, and a rotor assembly. The U-shaped cylinder 2 includes two vertical sections and a curved section connecting the two vertical sections. The plunger 1 is adapted to the vertical section of the U-shaped cylinder 2 and can move axially along the inner wall of the vertical section of the U-shaped cylinder 2 to compress the material 3 in the vertical section. The rotor assembly is disposed in another vertical section of the U-shaped cylinder 2. The rotor assembly includes a main rotor 6 located in the middle position and a first auxiliary rotor 10 and a second auxiliary rotor 4 located at the upper and lower ends of the main rotor 6, respectively. The main rotor 6, the first auxiliary rotor 10, and the second auxiliary rotor 4 form an annular slit die 5 between the main rotor 6, the first auxiliary rotor 10, and the second auxiliary rotor 4 and the inner wall of the vertical section of the U-shaped cylinder 2. The material 3 can flow through the annular slit die 5 under the compression of the plunger.

[0029] In this embodiment, the present invention comprises a U-shaped barrel 2, a plunger 1, and a rotor assembly. The rotor assembly includes a main rotor 6, a first auxiliary rotor 10, and a second auxiliary rotor 4. The main function of the auxiliary rotors at both ends of the main rotor 6 is to ensure that the material flow within the annular gap formed by the main rotor 6 and the U-shaped barrel 2 is in a fully developed flow state, while preventing material 3 from flowing into the gap between the rotors, thus avoiding the edge effect generated by the two auxiliary rotors at the ends from affecting the parameter measurement.

[0030] The U-shaped barrel 2 contains material 3. A heating device and a temperature sensor 7 are installed on the U-shaped barrel 2. The temperature sensor 7 measures the real-time temperature inside the barrel and performs closed-loop control to maintain a constant temperature during the material testing process. The temperature sensor 7 is installed on the wall of the U-shaped barrel 2, and the temperature control range is -10 to 150℃. The detection end of the temperature sensor 7 directly contacts the material 3 inside the U-shaped barrel 2 to detect the temperature of the material 3.

[0031] like Figure 1 As shown, the outer wall of the plunger 1 is sealed to the inner wall of the U-shaped barrel 2. The gap between the plunger 1 and the inner wall of the U-shaped barrel 2 is set to 0.25mm. The end of the plunger 1 away from the material 3 is connected to the plunger drive device. The plunger drive device is a constant speed drive system (threaded rod drive, speed control accuracy ±0.01mm / s). The plunger drive device can drive the plunger 1 to make linear reciprocating motion along the axial direction of the U-shaped barrel 2.

[0032] In this embodiment, gaps are provided between the main rotor 6 and the first auxiliary rotor 10 and the second auxiliary rotor 4. The width of the gaps is less than 0.1 mm, so that no material 3 flows into the gaps. Specifically, a main-auxiliary rotor gap 9 is provided between the main rotor 6, the second auxiliary rotor 4 and the first auxiliary rotor 10. The size of the main-auxiliary rotor gap 9 is set to 0.05 mm to prevent material 3 from flowing in, so as to avoid the edge effect of the second auxiliary rotor 4 and the first auxiliary rotor 10 from affecting the parameter measurement of the corresponding area of ​​the main rotor 6.

[0033] like Figure 2 As shown, the annular gap region formed by the main rotor 6 and the inner wall of the U-shaped barrel 2 is the fully developed flow region 8, while the annular gap region formed by the first auxiliary rotor 10, the second auxiliary rotor 4, and the inner wall of the U-shaped barrel 2 is the partially developed flow region. Two pressure sensors 12 for testing the pressure gradient are installed at both ends of the fully developed flow region 8. The pressure gradient value of the fully developed flow region 8 is calculated based on the data measured by the pressure sensors 12 placed within the annular gap, combined with the annular gap dimensions. The circumferential torque of the fully developed flow region 8 is directly measured by a circumferential torque testing system connected to the main rotor shaft 11. This circumferential torque testing system uses a torque sensor 13 connected to the main rotor shaft 11.

[0034] Example 2

[0035] like Figure 1 and Figure 3 As shown, a multifunctional rheological testing device includes a U-shaped cylinder 2, a plunger 1, and a rotor assembly. The U-shaped cylinder 2 includes two vertical sections and a curved section connecting the two vertical sections. The plunger 1 is adapted to the vertical section of the U-shaped cylinder 2 and can move axially along the inner wall of the vertical section of the U-shaped cylinder 2 to compress the material 3 in the vertical section. The rotor assembly is disposed in another vertical section of the U-shaped cylinder 2. The rotor assembly includes a main rotor 6 located in the middle position and a first auxiliary rotor 10 and a second auxiliary rotor 4 located at the upper and lower ends of the main rotor 6, respectively. The main rotor 6, the first auxiliary rotor 10, and the second auxiliary rotor 4 form an annular slit die 5 between the main rotor 6, the first auxiliary rotor 10, and the second auxiliary rotor 4 and the inner wall of the vertical section of the U-shaped cylinder 2. The material 3 can flow through the annular slit die 5 under the compression of the plunger.

[0036] In this embodiment, a software control system is also included to collect the displacement (grating ruler, accuracy ±0.001mm) and pressure gradient data of the plunger 1 in real time, and to calculate the shear stress and shear rate.

[0037] The mainstream field shear rate of this invention can be adjusted within a range of 10. -2～ 10 6 s -1 The frequency of the oscillating shear component is adjustable within a range of 10. -3～ 10 2 Hz, angular displacement resolution <1μrad, torque resolution <1μNm, temperature range from room temperature to 600℃, temperature stability <+ / -0.1℃, the specific working process is as follows:

[0038] Set the barrel temperature and wait for the temperature sensor 7 to stabilize (fluctuation ≤ ±0.1℃); after the U-shaped barrel 2 reaches and stabilizes at the set temperature, add material 3 from the right opening of the U-shaped barrel 2, and wait for the material temperature inside the U-shaped barrel 2 to remain constant at the set temperature. Figure 1As shown, the plunger drive device can control the plunger 1 to move at a constant speed via a motor; as Figure 3 As shown, the plunger drive device can also output a constant pressure to drive the plunger 1 by controlling the air pressure or hydraulic device. The plunger 1 squeezes the material in the U-shaped barrel 2, and through the annular die 5, forms a mainstream flow field with controllable shear rate. The annular die 5 area is mainly divided into three parts. The annular gap area formed by the main rotor 6 and the U-shaped barrel 2 is the fully developed flow zone 8, where the material flow is stable. However, the annular gap areas formed by the second auxiliary rotor 4 and the first auxiliary rotor 10 and the U-shaped barrel 2 have edge effects, and the material flow is unstable. Pressure sensors 12 are connected to both ends of the fully developed flow zone 8 on the inner wall of the U-shaped barrel 2 to test the axial pressure gradient in this area. By setting the parameters of the drive rotor motor, the rotor can achieve stationary, constant speed rotation, and oscillating rotation. With the help of the rotor assembly, the material 3 rotates circumferentially within the annular gap formed by the rotor and the barrel, forming a superimposed flow field perpendicular to the mainstream flow field. The torque sensor 13 is connected to the shaft of the main rotor 6 to measure the torque in the fully developed flow zone. Based on data such as plunger size and various motion parameters, rotor size and various motion parameters, shaft motion parameters, annular gap size, and pressure gradient in the fully developed flow region, parameters such as shear stress and shear rate of the main flow field and superimposed flow field are calculated, and various material functions are further obtained.

[0039] The movement of plunger 1 generates steady-state shear in the axial flow field. The rotation of the rotor assembly can generate steady-state or dynamic shear. The relatively stationary state of the rotor is regarded as steady-state shear with zero rotational speed. The waveform of the oscillating shear is a sine wave, sawtooth wave, rectangular wave or other random wave, including the following combinations: the rotor is stationary and only plunger 1 provides the axial flow field; the plunger 1 is stationary and only the rotor provides the circumferential (steady-state, dynamic or transient) flow field; both plunger 1 and rotor are moving and the main flow fields are orthogonally superimposed on the circumferential (steady-state, dynamic or transient) flow fields.

[0040] Example 3

[0041] like Figure 1 As shown, a multifunctional rheological testing device includes a U-shaped cylinder 2, a plunger 1, and a rotor assembly. The U-shaped cylinder 2 includes two vertical sections and a curved section connecting the two vertical sections. The plunger 1 is adapted to the vertical section of the U-shaped cylinder 2 and can move axially along the inner wall of the vertical section of the U-shaped cylinder 2 to compress the material 3 in the vertical section. The rotor assembly is disposed in another vertical section of the U-shaped cylinder 2. The rotor assembly includes a main rotor 6 located in the middle position and a first auxiliary rotor 10 and a second auxiliary rotor 4 located at the upper and lower ends of the main rotor 6, respectively. The main rotor 6, the first auxiliary rotor 10, and the second auxiliary rotor 4 form an annular slit die 5 between the main rotor 6, the first auxiliary rotor 10, and the second auxiliary rotor 4 and the inner wall of the vertical section of the U-shaped cylinder 2. The material 3 can flow through the annular slit die 5 under the compression of the plunger.

[0042] In this embodiment, the axes of all three rotors are parallel to the axis of the U-shaped barrel 2. The distance between the axis of the main rotor 6 and the axis of the U-shaped barrel 2 is less than the distance between the axes of the second auxiliary rotor 4 and the first auxiliary rotor 10 and the axis of the U-shaped barrel 2. By connecting an auxiliary rotor with a different shaft to each end of the main rotor and adjusting the gap between the rotors so that the material 3 cannot flow in, the fluid flow direction at both ends of the main rotor is only circumferential. This eliminates the influence of radial flow at both ends of a single rotor, avoids local velocity gradient anomalies and stress concentrations caused by uneven flow fields at both ends of the rotor, and eliminates parameter measurement errors caused by edge effects in the fully developed flow region.

[0043] The compression method of plunger 1 can be constant pressure or constant speed, that is, a constant speed is given to plunger 1 through a force transmission device or a constant pressure airflow is applied to plunger 1 through a constant pressure device, so as to precisely control the movement of plunger 1.

[0044] 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 multifunctional rheological testing device, characterized in that, The device includes a U-shaped barrel, a plunger, and a rotor assembly. The U-shaped barrel comprises two vertical sections and a curved section connecting the two vertical sections. The plunger is adapted to the vertical section of the U-shaped barrel and can move axially along the inner wall of the vertical section of the U-shaped barrel to compress the material within that vertical section. The rotor assembly is disposed in another vertical section of the U-shaped barrel. The rotor assembly includes a main rotor located in the middle and a first auxiliary rotor and a second auxiliary rotor located at the upper and lower ends of the main rotor, respectively. The main rotor, the first auxiliary rotor, and the second auxiliary rotor form an annular gap with the inner wall of the vertical section of the U-shaped barrel, through which the material can flow under the compression of the plunger.

2. The multifunctional rheological testing device according to claim 1, characterized in that, The U-shaped barrel is equipped with a heating device and a temperature sensor. The temperature sensor measures the real-time temperature inside the barrel and performs closed-loop control to keep the material at a constant temperature during the testing process.

3. The multifunctional rheological testing device according to claim 2, characterized in that, The temperature sensor is installed on the wall of the U-shaped cylinder, and the detection end of the temperature sensor directly contacts the material inside the U-shaped cylinder to detect the temperature of the material.

4. The multifunctional rheological testing device according to claim 1, characterized in that, The radial width of the circumferential gap formed between the inner wall of the U-shaped cylinder and the rotor assembly is 0.1 to 2 mm.

5. The multifunctional rheological testing device according to claim 1, characterized in that, There are gaps between the main rotor and the first auxiliary rotor and the second auxiliary rotor. The width of the gap is less than 0.1 mm, so that no material flows into the gap.

6. The multifunctional rheological testing device according to claim 1, characterized in that, The annular gap region formed by the main rotor and the U-shaped barrel is a fully developed flow region, while the annular gap region formed by the first auxiliary rotor, the second auxiliary rotor, and the U-shaped barrel is a partially developed flow region. Pressure sensors for testing pressure gradients are provided at both ends of the fully developed flow region.

7. A multifunctional rheological testing device according to claim 6, characterized in that, The pressure sensor is provided in at least two parts, and the detection ends of the pressure sensor are respectively placed at both ends of the fully developed flow zone of the annular gap.

8. A multifunctional rheological testing device according to claim 1, characterized in that, The main rotor's shaft is set along the axial center of the main rotor. One end of the main rotor shaft is fixedly connected to the main rotor, and the other end extends out of the U-shaped material cylinder and is connected to the motor that drives the rotor and the circumferential torque testing system.

9. A multifunctional rheological testing device according to claim 1, characterized in that, The outer wall of the plunger is sealed to the inner wall of the U-shaped cylinder, and the end of the plunger away from the material is connected to the plunger driving device. The plunger driving device can drive the plunger to make linear reciprocating motion along the axial direction of the U-shaped cylinder.

10. A multifunctional rheological testing device according to claim 1, characterized in that, The axes of the main rotor, the first auxiliary rotor, and the second auxiliary rotor are parallel.

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