Measurement system for determining physical properties of a fluid in a pipe-fluid system

Abstract

The invention relates to a measurement system for determining physical properties of a fluid in a pipe-fluid system, comprising a clamping element (3) arranged around the pipe-fluid system (150) and comprising a first clamping element (3a) and a second clamping element (3b), wherein the first clamping element (3a) and the second clamping element (3b) form a measurement section (4) corresponding to a section (2a) of the pipe-fluid system (150), an excitation system (5) configured to excite the pipe-fluid system (150) and to induce vibrations of the measurement system (100), a vibration sensing element (6) configured to measure the induced vibrations, and an element configured to break the symmetry of the measurement system (100) and the pipe-fluid system (150) in the circumferential direction of the measurement system (100) to influence the measurement spectrum measured by the vibration sensing element (6).

Description

Technical Field

[0001] This invention relates to a measurement system for determining the physical properties of fluids in a pipe-fluid system. Background Technology

[0002] A clamp-based vibration system for measuring one or more physical properties of a fluid typically consists of a pipe section constrained between two clamps, a device for vibration excitation, and a sensor for measuring the frequency of the pipe vibration. EP4036552A1, EP4273538A1, and US12163973B2 describe such measurement systems in the prior art.

[0003] This system links the frequency variation of selected vibration modes in a pipe-fluid system to physical properties.

[0004] Typically, a vibration sensor device is attached to the pipe, and the spectrum is measured at one or more defined coordinates corresponding to the pipe segment under consideration. The variation of the characteristic natural frequencies of the spectrum is then studied to assess changes in physical properties.

[0005] However, the drawback of this solution is that the vibration frequency can be introduced by the sensitivity to vibration, boundary conditions, clamps, or small defects in the pipe sections of the pipe-fluid system (e.g., due to manufacturing tolerances). This change can be misinterpreted as a change in the physical properties of the fluid in the pipe-fluid system, and thus lead to incorrect measurement of the fluid's physical properties.

[0006] Therefore, the design and tolerances of the constraint clamps, the tolerances / ellipticity of the pipe section, and external disturbances (such as forces caused by fluid flow or external vibrations) alter the spectrum at various locations on the pipe section of the pipe-fluid system.

[0007] In particular, the factors mentioned above can introduce peak splitting or additional interfering peaks into the spectrum recorded at the location of the vibration sensor by affecting the orientation of the vibration modes. Due to the cylindrical symmetry of the pipe-fluid system, the appearance of degenerate vibration modes in the spectrum, especially peak splitting, is typical for pipe vibration.

[0008] Peak splitting is caused by symmetry breaking, which depends on a variety of factors, including tolerances and external influences as described above. Furthermore, variations in process conditions (such as temperature or flow rate) can affect the symmetry of the system and thus alter the position or amount of splitting of interfering peaks. This can lead to inaccurate calculations of frequency variations, or misinterpretations of variations due to the frequency of interfering peaks, and consequently, lower accuracy or incorrect measurement in determining the physical properties of fluids in pipe-fluid systems.

[0009] These problems need to be addressed. Summary of the Invention

[0010] Therefore, it would be advantageous to provide a concept for improving the physical properties of fluids in pipe-fluid systems.

[0011] The object of the invention is achieved by the subject matter of the independent claims, wherein further embodiments are included in the dependent claims.

[0012] In a first aspect of the invention, a measurement system is provided for determining the physical properties of a fluid in a pipe-fluid system, the measurement system comprising:

[0013] A clamping element is arranged around a pipe-fluid system and includes a first clamping element and a second clamping element, wherein the first clamping element and the second clamping element form a measurement section corresponding to a section of the pipe-fluid system;

[0014] An excitation system configured to excite a tube-fluid system and induce vibrations in the measurement system;

[0015] A vibration sensing element configured to measure the induced vibration; and

[0016] An element configured to break the symmetry of the measurement system and the tube-fluid system in the circumferential direction of the measurement system in order to affect the measurement spectrum measured by the vibration sensing element.

[0017] In other words, an important aspect of this invention is to accurately measure the physical properties of fluids in pipe-fluid systems based on frequency analysis in an overall manner, in order to mitigate the effects of component tolerances and flow and disturbances that can hinder clear intrinsic frequency analysis of the pipes.

[0018] This invention allows for the adjustment and stabilization of the characteristics of a pipe-fluid system in such a way that the effects of component tolerances and external influences on the spectrum of the pipe-fluid system at the location of the vibration sensing element are negligible.

[0019] According to the invention, the element can be embodied in at least three different ways as described in detail in this patent application. In particular, advantageous effects can be achieved by using an element as an additional mass element or tuning element, which is arranged in some way or at a location near the vibration sensing element within the pipe-fluid system. Alternatively, clamping elements and / or damping elements can also contribute to achieving the aforementioned advantages of the invention.

[0020] In one example, the element is an additional mass element configured to tune the measured vibration at the resonant vibration sensing element. In this way, accurate and robust measurements of the fluid's physical properties can be achieved.

[0021] As one example, a mass element is attached to and / or near a vibration sensing element within the measurement section. In this way, accurate and robust measurements of the fluid's physical properties can be achieved.

[0022] As an example, the mass element is an integral part of the vibration sensing element. In this way, accurate and robust measurements of the physical properties of the fluid can be achieved.

[0023] In one example, the mass element is part of the pipe-fluid system itself. In this way, accurate and robust measurements of the fluid's physical properties become possible.

[0024] In one example, a mass element is positioned between the vibration sensing element and the pipe-fluid system. This allows for accurate and robust measurement of the fluid's physical properties.

[0025] According to one example, a mass element comprises multiple mass elements connected to the measurement section of a measurement system or pipe-fluid system. In this way, accurate and robust measurements of the physical properties of the fluid can be achieved.

[0026] As one example, multiple mass elements have different masses and / or the same mass. In this way, accurate and robust measurements of the physical properties of the fluid can be achieved.

[0027] In one example, a mass element is configured as an excitation system. This achieves a compact measurement system.

[0028] According to one example, the element at least partially includes clamping elements (3, 3a, 3b) configured as asymmetric clamping elements, which are configured to tune the measured vibration at the resonant vibration sensing element, and wherein the first and second clamping elements of the asymmetric clamping elements are further configured to influence the fluid-pipe system. In this way, accurate and robust measurement of the physical properties of the fluid can be achieved.

[0029] According to one example, the clamping element includes an elliptical inner profile for imprinting an elliptical shape onto the pipe-fluid system. In this way, accurate and robust measurements of the fluid's physical properties can be achieved.

[0030] According to one example, the clamping element includes multiple contact pins that enable contact with the pipe-fluid system. In this way, accurate and robust measurements of the fluid's physical properties can be achieved.

[0031] According to one example, the element includes a damping element attached to a pipe-fluid system, and / or the damping element is configured to perform non-contact damping. In this way, accurate and robust measurements of the fluid's physical properties can be achieved.

[0032] According to one example, the element is part of an excitation system and is configured to excite the pipe-fluid system at at least one defined location within a measurement section, and / or to define the intensity of the excitation at one or more coordinated excitation points in a circumferential direction around the pipe-fluid system within the measurement section. In this way, accurate and robust measurements of the physical properties of the fluid can be achieved. Attached Figure Description

[0033] Exemplary embodiments will now be described with reference to the following figures:

[0034] Figure 1 The illustration depicts a schematic (vibration) measurement system according to an embodiment of the present invention;

[0035] Figure 2a The illustration shows a schematic configuration of the components of a measurement system according to an embodiment of the present invention;

[0036] Figure 2b The illustration shows a schematic configuration of the components of a measurement system according to an embodiment of the present invention;

[0037] Figure 2c The illustration shows a schematic configuration of the components of a measurement system according to an embodiment of the present invention;

[0038] Figure 2d The illustration shows a schematic configuration of the components of a measurement system according to an embodiment of the present invention;

[0039] Figure 2e The illustration shows a schematic configuration of the components of a measurement system according to an embodiment of the present invention; and

[0040] Figure 2f The illustration shows a schematic configuration of the components of a measurement system according to an embodiment of the present invention. Detailed Implementation

[0041] Figure 1 Combination Figures 2a to 2f The illustration shows a schematic (vibration) measurement system 100 for determining the physical properties or physical parameters of the fluid 1 in the pipe-fluid system 150 or the pipe-fluid system 150.

[0042] A measurement system 100 for determining the physical properties or physical parameters (e.g., density, viscosity, flow parameters, etc.) of a fluid 1 (which may be a liquid or a gas) in a pipe-fluid system 150 includes clamping or constraining elements 3 arranged around the pipe-fluid system 150 and including a first clamping element 3a and a second clamping element 3b, wherein the first clamping element 3a and the second clamping element 3b form a measurement section 4 corresponding to a pipe section 2a of the pipe 2 of the pipe-fluid system 150.

[0043] The paired constraint elements 3 are configured to reduce surface vibration deformation at the outer surface of each end of the pipe-fluid system 150, wherein each constraint element 3, 3a, 3b may include a support frame configured to be detachably mounted on the pipe 2 of the pipe-fluid system 150.

[0044] In addition, the measurement system 100 includes an excitation system 5, which is configured to excite the tube-fluid system 150 and induce vibrations in the measurement system 100.

[0045] The excitation system 5 can be arranged at a first excitation position, which can be located around the circumference of the tube 2 within the measurement section 4 of the tube segment 2a. The tube segment 2a can be part of the measurement section 4.

[0046] Furthermore, the measurement system 100 includes a vibration sensing element 6 configured to measure induced vibrations and can be configured to generate a mechanical vibration spectrum at the surface of the pipe-fluid system 150. The vibration sensing element 6 may be an accelerometer. (As in...) Figure 1 As can be seen in the example, the vibration sensing element or sensing device 6 can be arranged at the measurement location within the measurement section 4 of the pipe segment 2a of the pipe 2.

[0047] The sensing element 6 can also be configured to be mechanically coupled to the outer surface of the pipe-fluid system 150 and configured to provide a mechanical vibration spectrum of the pipe-fluid system 150. The sensing element 6 can be, for example, a microphone.

[0048] The measuring system 100 may also include a fixing element configured to be detachably mounted for mechanically coupling the support frame to the outer surface of the tube 2 (not shown in the figure).

[0049] In another possible embodiment of the invention, the measurement system 100 may further include a support structure configured to support the excitation system 5 and enable the excitation system 5 to generate mechanical excitation; and a protective housing surrounding the pair of constraint elements 3, 3a, 3b, vibration sensing element or vibration sensing device 6 and the excitation system 5.

[0050] In addition, such as Figures 2a to 2f As shown, the measurement system 100 includes an element configured to break the symmetry of the measurement system 100 in the circumferential direction of the measurement system 100 and the pipe-fluid system 150 to affect the measurement spectrum measured by the vibration sensing element 6. The element is also configured to facilitate isolated vibration frequencies at the location of the vibration sensing element 6.

[0051] In this regard, it should be noted that the excitation affects not only the measurement system 100, but also the pipe-fluid system 150. This means that all entities involved in the vibration are: fluid 1, pipe 2, the overall pipe-fluid system 100, and the measurement system 100.

[0052] The pipe-fluid system 150 may also include a pipe 2. The pipe 2 contains the fluid 1.

[0053] In addition, such as Figure 1 As shown, in the example of the measurement system 100, a cantilever 8, which is part of the excitation system 5, is used to secure the excitation system 5.

[0054] In a possible first embodiment (category 1) of the invention concerning the breaking of symmetry, the element may be a mass element 7, which is mounted or arranged at different locations or sites on the pipe 2 of the pipe-fluid system 150, for example at any point around the circumference of the pipe in the measuring section 4 of the pipe 2, as described below, and particularly as in Figures 2a to 2f Various non-restrictive examples are shown.

[0055] In this way, the mass of the vibration sensing element 6 (attached to the tube 2) is increased, for example by placing an additional mass element on the vibration sensing element 6 (see...). Figure 1 The added mass element 7 can be a stainless steel column glued to the top of the vibration sensing element (accelerometer) 6. The total mass of the accelerometer and any possible additional weight can, for example, be advantageously about 0.1% greater than the mass of the tube segment constrained between the clamps 3, 3a, and 3b.

[0056] Due to the greater quality, signal degradation is significantly reduced (see...). Figures 2a to 2d This is manifested in the fact that the natural frequency appears to be well-defined (a single peak in the spectrum), which makes it possible to measure underlying physical properties under realistic conditions where there are component tolerances (e.g., ellipticity, diameter variation, wall thickness variation) and disturbances (e.g., flow, vibration).

[0057] As described above, component tolerances (such as ovality, diameter variation, wall thickness variation) and disturbances (such as flow, external vibration) can significantly affect the measured frequency spectrum of the tube section. Therefore, this susceptibility can be mitigated by deliberately breaking the symmetry of the system, for example by adding a tuning mass element to the accelerometer 6 or the tube 2 of the tube-fluid system 150.

[0058] Optionally, the element configured to break the symmetry of the measurement system (100) and the tube-fluid system (150) is an additional mass element 7, which is configured to tune the measured vibration at the vibration sensing element 6.

[0059] Optionally, the mass element or tuning element 7 is attached to the vibration sensing element 6 (see Figure 2a ) and / or adjacent to the vibration sensing element 6 within the measurement section 4 (see Figure 2b ).

[0060] Optionally, the vibration sensing element 6 may be fastened to the mass element 7, and the mass element 7 and / or the excitation system 5 are fastened to the tube.

[0061] Optionally, as shown in Figure 2c , the mass element 7 is arranged between the vibration sensing element 6 and the tube-fluid system 150.

[0062] Optionally, as shown in Figure 2d , the mass element 7 is an integral part of the vibration sensing element 6.

[0063] Optionally, as shown in Figure 2e , the mass element 7 is part of the tube-fluid system 150 itself. This may mean that the mass element 7 is mounted or arranged inside the tube 2 or is a part of the tube 2.

[0064] Optionally, as shown in Figure 2f , the mass element 7 may be embodied as the excitation system 5 and the vibration sensing element 6. The achieved advantage is that fewer components are required, for example cantilevers can be dispensed with, and better compactness of the measurement system is achieved.

[0065] Optionally, the mass element 7 may be embodied as the excitation system 5. The achieved advantage is that fewer components are required, for example cantilevers can be dispensed with, and better compactness of the measurement system is achieved.

[0066] Optionally, the mass element 7 comprises a plurality of mass elements within the measurement section 4.

[0067] Optionally, the multiple mass elements 7 may have different masses and / or the same mass. This means that multiple mass elements 7 are mounted on the measuring system 100, and these multiple mass elements 7 may have different masses and / or the same mass. The multiple mass elements 7 may be arranged at different locations around the circumference and / or axial position of the tube 2 within the measuring section 4.

[0068] Optionally, the mass element 7 can be located in the axial direction of the accelerometer / vibration sensor 6.

[0069] Optionally, the mass element 7 can be on the opposite side of the accelerometer (180°).

[0070] Optionally, the mass element 7 can be located in the axial direction of the excitation system 5. Optionally, the mass element 7 can be located on the opposite side (180°) of the excitation system 5.

[0071] Optionally, the mass element 7 can be variable and adjusted during commissioning to be minimized on one side but to eliminate unwanted asymmetry and splitting effects on the other side.

[0072] Optionally, the mass element 7 can be fixed to the threaded structure in the form of nuts of different sizes.

[0073] One can design a tuning process, such as monitoring / controlling the quality factor and / or spectrum of the measurement mode during the tuning process.

[0074] The following embodiments (Category 2) for the purpose of breaking symmetry involve specific designs of clamps 3, 3a, and 3b.

[0075] Optionally, the element includes at least in part clamping elements 3, 3a, 3b, which are configured as asymmetric clamping elements to tune the measured vibration at the vibration sensing element 6, and wherein the first clamping element 3a and the second clamping element 3b of the asymmetric clamping elements 3, 3a, 3b are further configured to influence the fluid-pipe system 150.

[0076] This effect can be, for example, but not limited to, a defined hardness. Or in other words, the first clamping element 3a is configured to apply a specific and defined mechanical effect, such as a specific stiffness, to the tube 2, which may be the same as or different from the mechanical effect (e.g., stiffness) applied by the second clamping element 3b mounted on the tube 2.

[0077] Optionally, the clamping elements 3, 3a, 3b include an elliptical inner contour for imprinting an elliptical shape onto the pipe-fluid system 150.

[0078] Optionally, the clamping elements 3, 3a, and 3b include a plurality of contact pins that enable contact with the pipe-fluid system 150. This means that the contact pins have an asymmetrical effect on the pipe 1 in the circumferential direction, thereby breaking the symmetry in the circumferential direction.

[0079] The following embodiments (Category 3) concerning symmetry breaking involve possible solutions by acting directly or indirectly on any point around the circumference of the tube in the measurement section.

[0080] Optionally, the element includes a damping element attached to the pipe-fluid system 150, for example, at a section of pipe 2 or at pipe segment 2a within the measuring section 4, and / or wherein the damping element is configured to implement non-contact damping at each occurrence using, for example, one of the following damping methods: electromagnetic damping, ultrasonic damping. Optionally, at least one separate damping element may be used in the pipe-fluid system 150.

[0081] Optionally, element 7 is part of excitation system 5 and is configured to excite pipe-fluid system 150 at at least one defined location within measurement section 4, and / or to define the intensity of excitation at one or more coordinated excitation points within measurement section 4 in a circumferential direction around pipe-fluid system 150. Furthermore, excitation system 5 is configured to apply a force to pipe 2 of pipe-fluid system 150 within measurement section 4 to induce vibration. Figure Labels

[0082] 1. Fluid

[0083] 2 tubes

[0084] 2 pipe sections

[0085] 3 Clamping elements / constraints

[0086] 3a First clamping element

[0087] 3b Second clamping element

[0088] 4. Measurement Section

[0089] 5. Incentive System

[0090] 6 Vibration sensing element

[0091] 7. Mass Components

[0092] 8 cantilever

[0093] 100 Measurement System

[0094] 150 Pipe-Fluid System

Claims

1. A measurement system (100) for determining the physical properties of a fluid (1) in a pipe-fluid system (150), comprising: A clamping element (3) is arranged around the pipe-fluid system (150) and includes a first clamping element (3a) and a second clamping element (3b), wherein the first clamping element (3a) and the second clamping element (3b) form a measurement section (4) corresponding to a section (2a) of the pipe-fluid system (150); An excitation system (5) is configured to excite the pipe-fluid system (150) and induce vibrations in the measurement system (100); A vibration sensing element (6) is configured to measure the vibration that is generated; as well as An element configured to break the symmetry of the measurement system (100) and the pipe-fluid system (150) in the circumferential direction of the measurement system (100) to affect the measurement spectrum measured by the vibration sensing element (6).

2. The measurement system (100) according to claim 1, wherein the element is an additional mass element (7) configured to tune the measured vibration at the vibration sensing element (6).

3. The measurement system (100) according to claim 2, wherein the mass element (7) is attached to the vibration sensing element (6) and / or near the vibration sensing element (6) within the measurement section (4).

4. The measurement system (100) according to any one of claims 2 to 3, wherein the mass element (7) is an integral part of the vibration sensing element (6).

5. The measurement system (100) according to any one of claims 2 to 3, wherein the mass element (7) is part of the pipe-fluid system (150) itself.

6. The measurement system (100) according to any one of claims 2 to 3, wherein the mass element (7) is arranged between the vibration sensing element (6) and the pipe-fluid system (150).

7. The measurement system (100) according to any one of claims 2 to 5, wherein the mass element (7) comprises a plurality of mass elements within the measurement section (4).

8. The measurement system (100) according to claim 7, wherein the plurality of mass elements have different masses and / or the same mass.

9. The measurement system (100) according to any one of the preceding claims, wherein the mass element (7) is configured as the excitation system (5).

10. The measurement system (100) of claim 1, wherein the element at least partially comprises the clamping elements (3, 3a, 3b), the clamping elements being configured as asymmetric clamping elements, the asymmetric clamping elements being configured to tune the measured vibration at the vibration sensing element (6), and / or wherein the first clamping element (3a) and the second clamping element (3b) of the asymmetric clamping elements (3, 3a, 3b) are further configured to influence the fluid-pipe system (150).

11. The measurement system (100) according to any one of the preceding claims, wherein the clamping elements (3, 3a, 3b) include an elliptical inner contour for imprinting an elliptical shape onto the tube-fluid system (150).

12. The measurement system (100) according to any one of the preceding claims, wherein the clamping elements (3, 3a, 3b) include a plurality of contact pins capable of contacting the pipe-fluid system (150).

13. The measurement system (100) according to any one of the preceding claims, wherein the element includes a damping element attached to the pipe-fluid system (150), and / or wherein the damping element is configured to perform non-contact damping.

14. The measurement system (100) according to any one of the preceding claims, wherein the element (7) is part of the excitation system (5) and is configured to excite the pipe-fluid system (150) at at least one defined location within the measurement section (4), and / or to define the intensity of the excitation at one or more coordinated excitation points within the measurement section (4) around the circumferential direction of the pipe-fluid system (150).

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