A non-newtonian fluid viscosity monitoring device and method

Abstract

The application provides a non-Newtonian fluid viscosity monitoring device and method, the non-Newtonian fluid viscosity monitoring device comprises a measuring tube, a wing-shaped elastomer, a strain detection assembly and a data processing unit, the measuring tube is used for accessing a fluid pipe and passing a fluid to be measured, the wing-shaped elastomer is arranged in the measuring tube, a chord direction of the wing-shaped elastomer is parallel to an axis of the measuring tube, the wing-shaped elastomer bears fluid resistance along the axis direction of the measuring tube under the action of the fluid, the strain detection assembly is arranged on a stress concentration area at the root of the wing-shaped elastomer, is used for detecting a bending strain signal generated by the wing-shaped elastomer under the action of the fluid, and the data processing unit is electrically connected with the strain detection assembly, is used for collecting the strain signal and calculating a viscosity index.The non-Newtonian fluid viscosity monitoring device not only has a simplified structure, no blockage and fast response, but also realizes online continuous monitoring.

Description

Technical Field

[0001] This invention belongs to the field of fluid viscosity measurement technology, and specifically relates to a non-Newtonian fluid viscosity monitoring device and method. Background Technology

[0002] Viscosity is an important parameter characterizing the flow properties of fluids. For non-Newtonian fluids, their viscosity varies with shear rate and often exhibits complex rheological behaviors such as yield stress and thixotropy. Traditional single-point viscosity measurements cannot fully describe their characteristics.

[0003] Existing methods for measuring the viscosity of non-Newtonian fluids mainly include rotational viscometers, tube flow methods, falling ball methods, and vibratory viscometers. Rotational viscometers can accurately measure rheological curves, but require sampling, cleaning, and temperature control, making online continuous monitoring impossible. Tube flow methods (pressure difference-flow rate) can be used for online measurement, but require measuring both pressure difference and flow rate, and the pressure orifice is easily clogged by mud. Falling ball methods require transparent tubes or photoelectric triggers and are not suitable for opaque fluids. Vibratory viscometers (such as tuning forks) can be used online, but the correspondence between their output signal and that of non-Newtonian fluids is complex, and the probe is prone to wear. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a non-Newtonian fluid viscosity monitoring device and method, which not only has a simplified structure, is non-clogging, and has a fast response, but also enables online continuous monitoring.

[0005] The technical solution of the present invention is as follows:

[0006] A non-Newtonian fluid viscosity monitoring device, comprising:

[0007] A measuring tube is used to connect to a fluid pipeline and allow the fluid to be measured to pass through.

[0008] An airfoil elastomer is disposed inside the measuring tube, the chord direction of the airfoil elastomer is parallel to the axis of the measuring tube, and the airfoil elastomer bears the fluid resistance along the axis of the measuring tube under the action of fluid;

[0009] A strain detection component is disposed on the stress concentration area at the root of the airfoil elastomer and is used to detect the bending strain signal generated by the airfoil elastomer under the action of fluid.

[0010] The data processing unit is electrically connected to the strain detection component and is used to acquire strain signals and calculate the viscosity index.

[0011] Furthermore, in the aforementioned non-Newtonian fluid viscosity monitoring device, the airfoil elastomer has a symmetrical airfoil structure; and / or,

[0012] The root of the airfoil elastomer is fixed to the inner wall of the measuring tube in a detachable or non-detachable manner; and / or,

[0013] The measuring tube is provided with a first flange at each end, the first flange being used to connect to a fluid pipeline; and / or,

[0014] The measuring tube has a cylindrical structure.

[0015] Furthermore, in the aforementioned non-Newtonian fluid viscosity monitoring device, the detachable connection method is through a second flange connection, and the non-detachable connection method is welding.

[0016] Furthermore, in the non-Newtonian fluid viscosity monitoring device, the strain detection component includes multiple full-bridge strain gauges, which are distributed and attached to the stress concentration area at the root of the elastomer.

[0017] Furthermore, the non-Newtonian fluid viscosity monitoring device also includes a temperature sensor installed inside the measuring tube to detect the fluid temperature inside the measuring tube. The data processing unit uses the fluid temperature to perform temperature compensation correction on the strain-viscosity relationship to obtain a temperature-compensated viscosity index.

[0018] Furthermore, in the aforementioned non-Newtonian fluid viscosity monitoring device, the data processing unit includes:

[0019] The signal conditioning circuit is used to receive the strain signal output by the strain detection component, and to amplify and filter the strain signal to generate a conditioned strain voltage signal.

[0020] An analog-to-digital converter, connected to the output of the signal conditioning circuit, is used to convert the conditioned strain voltage signal into raw digital strain data.

[0021] A microprocessor is connected to the output of the analog-to-digital converter. The microprocessor has a built-in pre-calibrated strain-viscosity relationship model, which is used to calculate the viscosity index based on the original digital strain data and the pre-calibrated strain-viscosity relationship model.

[0022] A method for monitoring the viscosity of a non-Newtonian fluid includes the following steps:

[0023] S1: The fluid to be tested is introduced into the measuring tube at a set flow rate, and the airfoil elastomer inside the measuring tube withstands the fluid resistance along the axial direction of the measuring tube.

[0024] S2: Acquire the bending strain signal generated by the airfoil elastomer under the action of fluid resistance;

[0025] S4: Based on a pre-calibrated strain-viscosity relationship model, the bending strain signal is converted into the viscosity index of the fluid.

[0026] Furthermore, in the non-Newtonian fluid viscosity monitoring method, the step between S2 and S4 further includes:

[0027] S3: Detect the fluid temperature inside the measuring tube, and perform temperature compensation on the bending strain signal based on the fluid temperature to obtain a temperature-compensated bending strain signal;

[0028] In step S4, the temperature-compensated bending strain signal is used for conversion.

[0029] Furthermore, in the non-Newtonian fluid viscosity monitoring method, after step S4, the method further includes:

[0030] S5: Output the monitoring results of the viscosity index; and / or,

[0031] S6: Compare the viscosity index with a preset viscosity threshold, and issue an alarm when the viscosity index exceeds the viscosity threshold.

[0032] Furthermore, in the non-Newtonian fluid viscosity monitoring method, the viscosity index is the relative viscosity index or the apparent viscosity index.

[0033] The beneficial effects of this invention are as follows:

[0034] This invention discloses a non-Newtonian fluid viscosity monitoring device. By setting an airfoil elastomer inside the measuring tube and setting a strain detection component on the airfoil elastomer, the device can monitor the viscosity of non-Newtonian fluids. It not only has a simplified structure, low cost, and is easy to install and maintain, but also has a fast response speed, making it suitable for process control. Furthermore, it has no pressure measuring hole and no dynamic seal, avoiding the problems of easy clogging and easy leakage of dynamic seals caused by traditional differential pressure methods. It is particularly suitable for online monitoring of non-Newtonian slurries containing solid phases. Attached Figure Description

[0035] Figure 1 This is a partial cross-sectional schematic diagram of a non-Newtonian fluid viscosity monitoring device according to the present invention;

[0036] Figure 2 yes Figure 1 Enlarged view of point A in the middle;

[0037] Figure 3 This is a flowchart of a non-Newtonian fluid viscosity monitoring method according to the present invention.

[0038] In the figure: 1. Measuring tube; 2. Airfoil elastomer; 3. Strain detection assembly; 4. Data processing unit; 5. Temperature sensor; 11. First flange; 12. Sealing hole; 21. Second flange; 31. Full-bridge strain gauge; 32. Lead wire. Detailed Implementation

[0039] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0040] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected" and "fixed" 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 or an electrical 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 invention based on the specific circumstances.

[0042] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0043] Example 1:

[0044] like Figure 1 and Figure 2 As shown, this embodiment provides a non-Newtonian fluid viscosity monitoring device, which includes a measuring tube 1, an airfoil elastomer 2, a strain detection component 3, and a data processing unit 4, and may also include a temperature sensor 5.

[0045] The measuring tube 1 can be configured as a cylindrical structure with an inner diameter of 200mm made of stainless steel. Each end of the measuring tube 1 is provided with a first flange 11, which is used to connect in series to the fluid pipeline to be monitored, allowing all the fluid to be measured to pass through the measuring tube 1.

[0046] An airfoil elastomer 2 is disposed inside the measuring tube 1. The airfoil elastomer 2 can adopt a NACA0012 symmetrical airfoil structure, with a chord length of 120 mm, a relative thickness of 10%, and a material of 17-4PH stainless steel, exhibiting good elasticity and corrosion resistance. The symmetrical airfoil structure ensures stable flow field and good linearity at zero angle of attack, guaranteeing the reliability and consistency of viscosity measurement through standardized and mature airfoil design. The chord direction of the airfoil elastomer 2 is parallel to the axis of the measuring tube 1, serving to withstand fluid resistance (including differential pressure resistance and viscous friction resistance) along the axis of the measuring tube 1 under fluid action, and generating corresponding bending deformation. The root of the airfoil elastomer 2 is detachably fixed to the inner wall of the measuring tube 1 via a second flange 21, which is bolted to the tube wall. In other embodiments, the second flange 21 can also be directly fixed to the inner wall of the measuring tube 1 by welding or other non-detachable methods.

[0047] The strain detection component 3 is disposed on the stress concentration area at the root of the airfoil elastomer 2, and is used to detect the bending strain signal generated by the airfoil elastomer 2 under the action of fluid. The strain detection component 3 includes multiple full-bridge strain gauges 31, which are distributed and attached to the stress concentration area at the root of the elastomer. Four full-bridge strain gauges 31 can be used, with two full-bridge strain gauges 31 attached to the upper surface of the root of the airfoil elastomer 2, and the other two full-bridge strain gauges 31 attached to the lower surface of the root of the airfoil elastomer 2, forming a full bridge. A full-bridge circuit is used for connection to maximize detection sensitivity and achieve self-temperature compensation.

[0048] It may also include a temperature sensor 5. The temperature sensor 5 may be a PT100 platinum resistance thermometer. The temperature sensor 5 is installed on the inner wall of the measuring tube 1 and is used to detect the fluid temperature inside the measuring tube 1.

[0049] The data processing unit 4 is electrically connected to the strain detection component 3 and the temperature sensor 5, and is used to acquire strain signals, fluid temperature, and calculate viscosity index. The data processing unit 4 includes a signal conditioning circuit, an analog-to-digital converter, and a microprocessor.

[0050] The signal conditioning circuit receives the strain signal output from the strain detection component 3 and the temperature signal output from the temperature sensor 5, and amplifies and filters the strain signal to generate a conditioned strain voltage signal and temperature voltage signal. The strain detection component 3 is connected to the signal conditioning circuit via a lead 32, which passes through the sealing hole 12 of the measuring tube 1. The temperature sensor 5 is electrically connected to the signal conditioning circuit.

[0051] The analog-to-digital converter is connected to the output of the signal conditioning circuit to convert the two signals into digital strain raw data and digital temperature raw data.

[0052] The microprocessor is connected to the output of the analog-to-digital converter via a digital bus. The microprocessor incorporates a pre-calibrated strain-viscosity relationship model and a temperature compensation algorithm. After reading the raw digital strain and temperature data, the microprocessor first performs temperature compensation correction on the viscosity calculation based on the raw digital temperature data, and then calculates the viscosity index of the fluid at the current temperature based on the strain-viscosity relationship model. This viscosity index can be either the relative viscosity index or the apparent viscosity index.

[0053] During installation, the four full-bridge strain gauges 31 of the strain detection assembly 3 can be first attached to the root of the airfoil elastomer 2. Then, the airfoil elastomer 2 can be installed on the inner wall of the measuring tube 1 through the second flange 21, so that the chord direction of the airfoil elastomer 2 is parallel to the axis of the measuring tube 1. The airfoil elastomer 2 bears the fluid resistance along the axis direction (fluid flow direction) of the measuring tube 1 under the action of fluid. The leads 32 of the four full-bridge strain gauges 31 are passed through the sealing hole 12 of the measuring tube 1 and connected to the data processing unit 4.

[0054] Monitoring Process: The fluid to be tested is introduced into the measuring tube 1 at a set flow rate of 20 L / min. The airfoil elastomer 2 inside the measuring tube 1 withstands the fluid resistance along the axis of the measuring tube 1. A strain detection assembly 3, composed of four full-bridge strain gauges 31, collects the bending strain signal generated by the airfoil elastomer 2 under the action of fluid resistance in real time. A temperature sensor 5 synchronously detects the fluid temperature inside the measuring tube 1, and a data processing unit 4 performs temperature compensation on the bending strain signal based on the fluid temperature to obtain a temperature-compensated bending strain signal. The data processing unit 4 converts the bending strain signal into the viscosity index of the fluid according to a pre-calibrated strain-viscosity relationship model. The data processing unit 4 substitutes the temperature-compensated strain voltage value U into the calibration model U = 0.02η + 0.5 to calculate the current apparent viscosity η. This apparent viscosity η is one type of viscosity index. Further, the currently calculated apparent viscosity η can be divided by a preset reference viscosity value to obtain the relative viscosity index.

[0055] The above structure, by setting an airfoil elastomer 2 inside the measuring tube 1 and setting a strain detection component 3 on the airfoil elastomer 2, realizes the monitoring of the viscosity of non-Newtonian fluids. It is not only simple in structure, low in cost, and easy to install and maintain, but also has a fast response speed, making it suitable for process control. Furthermore, it has no pressure measuring hole and no dynamic seal, avoiding the problems of easy clogging and easy leakage of dynamic seals caused by traditional differential pressure methods. It is particularly suitable for online monitoring of non-Newtonian mud containing solid phases.

[0056] Example 2:

[0057] The pre-calibrated strain-viscosity relationship model is the basis for the measurements performed by the device of this invention. This embodiment uses Newtonian fluid as the measurement reference, and the calibration steps are as follows:

[0058] First, connect the device to the circulation pipeline and adjust the flow control valve to keep the flow rate constant at the set flow rate of 20L / min.

[0059] Then, three Newtonian fluids (silicone oils) of known viscosity were sequentially introduced into the pipeline. The standard viscosities η of these three silicone oils at 25°C were 10 mPa·s, 50 mPa·s, and 100 mPa·s, respectively. After ensuring that each fluid filled the pipeline and that the flow rate and temperature were stable, the corresponding strain voltage value U collected by the data processing unit 4 was recorded.

[0060] Finally, a relationship curve was plotted with standard viscosity η as the abscissa and strain voltage U as the ordinate. For the device parameters of this embodiment, the curve exhibits a good linear relationship, and the linear equation obtained by fitting is U = 0.02η + 0.5 (in mV). This linear equation is used as a pre-calibrated strain-viscosity relationship model and stored in the microprocessor, thus completing the calibration.

[0061] The calibration method described above uses Newtonian fluid calibration to establish a benchmark for non-Newtonian fluid measurements. This method is simple and efficient, and the resulting linear model is stable and reliable, allowing it to be directly embedded into the data processing unit 4 for online calculations.

[0062] Example 3:

[0063] like Figure 3 As shown, this embodiment also provides a method for monitoring the viscosity of non-Newtonian fluids, including the following steps: S1-S4, and may also include S5-S6.

[0064] S1: The fluid to be tested (e.g., drilling fluid) is introduced into the measuring tube 1 at a set flow rate of 20 L / min. The airfoil elastomer 2 inside the measuring tube 1 bears the fluid resistance along the axial direction of the measuring tube 1.

[0065] S2: The strain detection assembly 3, consisting of four full-bridge strain gauges 31, collects the bending strain signal generated by the airfoil elastomer 2 under the action of fluid resistance in real time.

[0066] S3: The temperature of the fluid in the measuring tube 1 is detected synchronously by the temperature sensor 5, and the bending strain signal is temperature compensated by the data processing unit 4 according to the fluid temperature to obtain the temperature compensated bending strain signal.

[0067] S4: Data processing unit 4 converts the bending strain signal into the viscosity index of the fluid according to a pre-calibrated strain-viscosity relationship model. Data processing unit 4 substitutes the temperature-compensated strain voltage value U into the calibration model U = 0.02η + 0.5 to calculate the current apparent viscosity η. This apparent viscosity η is one type of viscosity index. Further, the currently calculated apparent viscosity η can be divided by a preset reference viscosity value to obtain the relative viscosity index.

[0068] After step S4, steps S5-S6 may also be included.

[0069] S5: Output the monitoring results of the viscosity index. The monitoring results can be the apparent viscosity value or the relative viscosity index.

[0070] S6: Compare the viscosity index with a preset viscosity threshold, and issue an alarm when the viscosity index exceeds the viscosity threshold. For example, when using a relative viscosity index, the preset threshold is in the range of 0.8 to 1.2; exceeding this range will trigger an alarm, indicating abnormal fluid performance.

[0071] The above monitoring method obtains the viscosity index online by directly measuring the bending force of the fluid on the airfoil elastomer 2 inside the pipe. It requires no sampling and has no moving parts, thus realizing real-time, continuous, and maintenance-free monitoring of the viscosity of non-Newtonian fluids.

[0072] By comparing the results with those obtained from timed sampling measurements using a standard rotational viscometer, the viscosity change trend reflected by the device of this invention throughout the entire monitoring period is highly consistent with the standard method, demonstrating the reliability and engineering practical value of the present invention.

[0073] In the description of this specification, references to terms such as "an embodiment," "example," etc., 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 the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0074] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0075] The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of the invention and should not be construed as limiting the scope of protection of the invention in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of the invention without inventive effort, and these embodiments will all fall within the scope of protection of the present invention.

Claims

1. A non-Newtonian fluid viscosity monitoring device, characterized in that, include: Measuring tube (1) is used to connect to a fluid pipeline and allow the fluid to be measured to pass through; An airfoil elastomer (2) is disposed inside the measuring tube (1). The chord direction of the airfoil elastomer (2) is parallel to the axis of the measuring tube (1). The airfoil elastomer (2) bears the fluid resistance along the axis of the measuring tube (1) under the action of the fluid. The strain detection component (3) is set on the stress concentration area at the root of the airfoil elastomer (2) and is used to detect the bending strain signal generated by the airfoil elastomer (2) under the action of fluid. The data processing unit (4) is electrically connected to the strain detection component (3) and is used to collect strain signals and calculate the viscosity index.

2. The non-Newtonian fluid viscosity monitoring device as described in claim 1, characterized in that, The airfoil elastomer (2) is a symmetrical airfoil structure; and / or, The root of the airfoil elastomer (2) is fixed to the inner wall of the measuring tube (1) in a detachable or non-detachable manner; and / or, The measuring tube (1) is provided with a first flange (11) at each end, the first flange (11) being used to connect to a fluid pipeline; and / or, The measuring tube (1) has a cylindrical structure.

3. The non-Newtonian fluid viscosity monitoring device as described in claim 2, characterized in that, The detachable connection method is through the second flange (21), and the non-detachable connection method is welding.

4. The non-Newtonian fluid viscosity monitoring device as described in claim 1, characterized in that, The strain detection component (3) includes multiple full-bridge strain gauges (31), which are distributed and attached to the stress concentration area at the root of the elastomer.

5. The non-Newtonian fluid viscosity monitoring device as described in claim 1, characterized in that, It also includes a temperature sensor (5), which is installed inside the measuring tube (1) to detect the fluid temperature inside the measuring tube (1). The data processing unit (4) performs temperature compensation correction on the strain and viscosity relationship based on the fluid temperature to obtain a temperature-compensated viscosity index.

6. The non-Newtonian fluid viscosity monitoring device as described in claim 1, characterized in that, The data processing unit (4) includes: The signal conditioning circuit is used to receive the strain signal output by the strain detection component (3) and amplify and filter the strain signal to generate a conditioned strain voltage signal. An analog-to-digital converter, connected to the output of the signal conditioning circuit, is used to convert the conditioned strain voltage signal into raw digital strain data. A microprocessor is connected to the output of the analog-to-digital converter. The microprocessor has a built-in pre-calibrated strain-viscosity relationship model, which is used to calculate the viscosity index based on the original digital strain data and the pre-calibrated strain-viscosity relationship model.

7. A method for monitoring the viscosity of a non-Newtonian fluid, characterized in that, Includes the following steps: S1: The fluid to be tested is introduced into the measuring tube (1) at a set flow rate. The airfoil elastomer (2) inside the measuring tube (1) bears the fluid resistance along the axial direction of the measuring tube (1). S2: Collect the bending strain signal generated by the airfoil elastomer (2) under the action of fluid resistance; S4: Based on a pre-calibrated strain-viscosity relationship model, the bending strain signal is converted into the viscosity index of the fluid.

8. The method for monitoring the viscosity of non-Newtonian fluids as described in claim 7, characterized in that, Between steps S2 and S4, the following is also included: S3: Detect the fluid temperature inside the measuring tube (1), and perform temperature compensation on the bending strain signal according to the fluid temperature to obtain the temperature-compensated bending strain signal; In step S4, the temperature-compensated bending strain signal is used for conversion.

9. The method for monitoring the viscosity of non-Newtonian fluids as described in claim 7, characterized in that, Following step S4, the following is also included: S5: Output the monitoring results of the viscosity index; and / or, S6: Compare the viscosity index with a preset viscosity threshold, and issue an alarm when the viscosity index exceeds the viscosity threshold.

10. The method for monitoring the viscosity of non-Newtonian fluids as described in claim 7, characterized in that, The viscosity index is either the relative viscosity index or the apparent viscosity index.

Images