Diagnostic method for flow measuring device with active pressure line

Abstract

The invention relates to a diagnostic method for a flow measuring device having an effective pressure line, the flow measuring system being attached to a through-flow pipe in which an orifice plate is arranged. In a first step, a fluid is passed through the conduit and an effective pressure in one of the effective pressure lines is acquired. In a second step, a vibration variable of the vibration is acquired via a vibration sensor disposed in the region of the orifice plate. In a third step, a blockage of the effective pressure line is detected if the quantity of the effective pressure detected in the first step is below an adjustable first threshold value and the quantity of the vibration variable detected in the second step is above an adjustable second threshold value. If a jam of the effective pressure line is identified, an alert is output to a user and / or a data interface. The invention also relates to a computer program product which can be used to carry out a diagnostic method and to an evaluation unit.

Description

Technical Field

[0001] The invention relates to a diagnostic method for a flow measuring device with an effective pressure line. The invention also relates to a computer program product and a corresponding evaluation unit that can be used to implement such a diagnostic method. The invention also relates to a correspondingly equipped flow measuring system and a simulation program product. The invention also relates to the use of a vibration sensor for detecting a blockage in the effective pressure line. Background Art

[0002] Patent application DE 10 2006 004 582 A1 discloses a method for diagnosing a blockage of an impulse line in a pressure transmitter. In this case, a differential pressure sensor is connected to the line via a first and a second impulse line. The pressure difference at the two impulse lines and, if necessary, the individual pressures are determined. Based on this, a characteristic value is determined and compared with a reference value.

[0003] International application WO 01 / 69182 A2 discloses a sensor device for flow measurement, which is attached to a line through which a flow passes. The sensor device comprises a vibration sensor coupled to an evaluation unit. The vibration sensor is designed as a piezoelectric film sensor. With the aid of the evaluation unit, a flow parameter is determined based on a vibration variable.

[0004] Patent application US2009 / 0326839A1 discloses a diagnostic method for a flow measuring device which is connected to a differential pressure measuring device via two effective pressure lines. The effective pressure lines are attached to the pipeline to obtain the effective pressure in the pipeline in the region of the orifice. In normal operation, the orifice in the pipeline is traversed by the fluid in the pipeline.

[0005] Flow measuring devices with orifice plates are used in many industrial applications. Such flow measuring devices can become inoperable due to contamination during operation. Such flow measuring devices are also subject to wear. There is therefore a need for a diagnostic option by means of which faults and / or wear in such flow measuring devices can be identified in a reliable and cost-effective manner. The object on which the invention is based is to provide an option which provides an improvement in at least one of these aspects. Summary of the invention

[0006] This object is achieved by a diagnostic method according to the present invention, which is used to diagnose a flow measurement system including a flow measurement device. The flow measurement system is attached to a pipeline that can be traversed by a fluid (i.e., a liquid or a gas). An orifice plate is arranged in the pipeline. Through the orifice plate, a pressure difference related to the flow rate can be generated in front of and behind the orifice plate relative to the flow direction. The flow measurement system includes at least two effective pressure lines connected to the flow measurement device. The pressure currently present there can be recorded in the region of the orifice plate, i.e., in front of or behind it, respectively, via at least two effective pressure lines. For this purpose, one of the effective pressure lines is arranged to obtain the pressure in front of the orifice plate, and one of the effective pressure lines is arranged to obtain the pressure behind the orifice plate. The terms "front" and "rear" are relative to the flow direction. The effective pressure line is arranged at a position far upstream or downstream from the orifice plate, so that the pressure effect of the orifice plate can still be evaluated in a technically meaningful manner at the flow rate to be measured.

[0007] The diagnostic method comprises a first step, in which a fluid flows through the pipeline and the effective pressure in one of the effective pressure lines is detected. In a second step, a vibration variable of the vibration is detected. For this purpose, a vibration sensor is fixed in the region of the orifice plate. In this case, the vibration sensor can be located so far away from the orifice plate in the axial direction of the pipeline that the vibration variable occurring there can still be evaluated in a technically meaningful manner, i.e., for example with a sufficient signal-to-noise ratio. The vibration variable can be an amplitude, a frequency and / or a magnitude derived therefrom.

[0008] In addition, the diagnostic method has a third step, in which the following blockage of the effective pressure circuit is identified, and the effective pressure is obtained in the first step at the effective pressure circuit. If the magnitude of the effective pressure obtained in the first step is lower than the adjustable first threshold value and the magnitude of the vibration variable obtained in the second step is higher than the adjustable second threshold value, the blockage is identified. Here, being lower than the first adjustable threshold value and exceeding the second adjustable threshold value can occur substantially at the same time or within a preset recognition interval. The lowering of the effective pressure below the first adjustable threshold value indicates that the corresponding effective pressure circuit is potentially blocked, i.e. blocked, or the pipeline is not flowed through with a sufficient flow rate. If there is a sufficiently strong vibration at the same time, i.e. the magnitude of the vibration variable exceeds the second adjustable threshold value, it indicates that the flow continues through the orifice plate. As a result, it is verified that the reduction of the effective pressure magnitude below the first threshold value is caused by the blockage of the corresponding effective pressure circuit due to the magnitude exceeding the second adjustable threshold value. The vibration of the vibration variable obtained in the second step is caused by the non-steady-state flow phenomenon at the orifice plate. In particular, turbulence is caused when the orifice plate is flowed through in the fluid, and the turbulence causes vibration. Furthermore, in the diagnostic method according to the invention, a warning is output to a user and / or a data interface when a blockage of the corresponding effective pressure line is detected.

[0009] The first threshold value and the second threshold value can be preset, i.e. set, respectively, by user input, a table of values, a characteristic curve, an algorithm and / or artificial intelligence. Thus, the diagnostic method according to the invention can be adapted to a wide range of pipeline sizes and orifice plates of different sizes and configurations. Likewise, the first and / or second threshold values ​​can be optimized by machine learning. In addition to the orifice plate and the effective pressure line, the diagnostic method according to the invention does not require any other components in the inner cavity of the pipeline that affect its flow. In addition, the vibration sensor can be installed in a simple manner in the area of ​​the orifice plate. Thus, the diagnostic method according to the invention can be quickly and cost-effectively applied to existing pipelines with built-in orifice plates.

[0010] In one embodiment of the claimed diagnostic method, the orifice plate is attached to at least one annular flange, by which a first pipe and a second pipe belonging to the pipeline are connected to each other. The annular flange can be configured to surround the orifice plate at its circumference and thereby fasten it. The vibrations caused by the perforated plate are thus transmitted to the annular flange. In addition, the vibration sensor can be fixed to the annular flange or to the pipeline itself, i.e. to the first pipe or the second pipe. There are sufficiently strong vibration variables there, which can also be accurately acquired with the aid of relatively simple vibration sensors. Therefore, the claimed diagnostic method can be implemented cost-effectively.

[0011] In addition, the diagnostic method may also include a fourth step, in which an artificial intelligence is trained according to the measured value of the effective pressure and at least one vibration variable. In addition, the flow rate determined by means of a flow measurement device can also be used during training. Through the training in the fourth step, the reference state of the orifice plate is determined. For example, the reference state can be a good state that exists after the new orifice plate is installed. In addition, the diagnostic method can have a fifth step, in which the wear of the orifice plate is identified. Here, the reference state determined in the fourth step is related to the current effective pressure, at least one current vibration variable and / or a variable derived individually or in combination. In addition, the flow rate determined by means of a flow measurement device can also be used for comparison in the fifth step. By comparing in the fifth step, it is possible to quantify how much the orifice plate deviates from the reference state and whether to provide a replacement of the orifice plate. Similarly, it is possible to determine the expected operating duration before providing an orifice plate replacement. The expected operating duration is determined by considering the disclosure of the description of the particle content and / or particle properties in the fluid. The particles have an abrasive effect, which includes but is not limited to being related to their hardness, sharpness and concentration in the fluid. The orifice plate is durable and exhibits constant characteristics over a sufficiently long operating duration. The reference state can thus be reliably learned by training, in particular in so-called machine learning. The same applies to determining the expected operating time until the orifice plate has to be replaced.

[0012] In a further embodiment of the claimed diagnostic method, the flow measuring device is designed as a differential pressure measuring device. The differential pressure measuring device is suitable for determining a pressure difference between at least two effective pressure lines, which is a measure of the fluid flow rate present at the orifice. The effective pressure lines can be arranged in the flow direction in front of and behind the orifice. Such a flow measuring device has an increased sensitivity to blocked effective pressure lines, so that errors occurring during operation can be quickly identified with the aid of the claimed diagnostic method.

[0013] In addition, the effective pressure line can have a length of 1 m to 20 m in each case. One or more effective pressures can thereby be acquired remotely by the vibration sensor. The vibration sensor and the flow measurement device at which the effective pressure line ends can be coupled to the evaluation unit via a communication data link in each case. The communication data link can be configured as a wired connection or a radio connection in each case. Thus, the hardware for the claimed diagnostic method is modular. In particular, the vibration sensor can be selected independently of the flow measurement device.

[0014] In addition, the vibrations acquired by the vibration sensor in the second step can be oriented perpendicular to the axial direction of the pipeline. In particular, the acquired vibrations can be perpendicular to the axial direction of the pipeline in the region of the orifice plate. The axial direction is defined by the pipe axis of the pipeline. Therefore, vibrations in the radial direction are acquired by means of the vibration sensor. The vibrations caused by the perforated plate have an increased amplitude in the radial direction due to the shape of the pipe and / or the annular flange. As a result, an increased signal-to-noise ratio (also referred to as SNR) can be achieved. Therefore, the achievable accuracy when acquiring the vibrations is thereby achieved, which in turn allows early identification of blockages in the corresponding effective pressure line. The early warning effect is thereby improved.

[0015] In another embodiment of the claimed diagnostic method, the diagnostic method can include a sixth step, in which a first measured value of the flow rate of the fluid in the pipeline is determined. The first measured value of the flow rate is determined based on the effective pressure obtained in the first step. In addition, the diagnostic method includes a seventh step, in which a second measured value of the flow rate is determined. The determination of the second measured value of the flow rate begins with the vibration variable obtained in the second step. Artificial intelligence is used to determine the second measured value of the flow rate. In addition, in the claimed diagnostic method, the first measured value is compared with the second measured value. The rationality of the measured values ​​is checked against each other based on the comparison. For example, the difference between the first measured value and the second measured value can be determined, and its magnitude is compared with a preset limit value. If the magnitude of the determined difference is less than the preset limit value, a well-functioning state of the flow measurement system is identified. However, in the case where the magnitude exceeds the preset limit value, it is identified that an abnormal state exists at the vibration sensor, at the effective pressure line, or at the flow measurement device. If an abnormal state is identified, a warning can be output to the user and / or the data interface. The vibration sensor and the effective pressure line or the flow measuring device are based on different physical principles of action and thus differ from each other. The claimed diagnostic method therefore allows reliable identification of whether a flow measuring system comprising a vibration sensor is still functioning well. The claimed diagnostic method is therefore self-monitoring. In addition, the wear of the orifice plate can be identified by comparison between the first measured value and the second measured value. For example, the wear of the orifice plate causes a reduction in the differential state that can be obtained on the effective pressure line when the flow remains unchanged. However, the formation of turbulence at the orifice plate is only slightly affected by abrasion. The wear of the orifice plate can therefore be determined from the difference between the first measured value and the second measured value.

[0016] The purpose on which it is based is also achieved by a computer program product according to the invention, which is configured to receive and process measured values ​​of effective pressure and at least one vibration variable. According to the invention, the computer program product is configured to execute at least one of the above-mentioned embodiments of the diagnostic method claimed. The computer program product can be hardwired, configured as software or configured as a combination thereof. In particular, the computer program product can be configured at least partially as a chip, an integrated circuit and / or an FPGA. In addition, the computer program product can be configured monolithically, that is, on a single hardware platform. Alternatively, the computer program product can be modularly configured and include multiple subroutines that run on different hardware platforms and collaborate via communication data links (e.g., Internet connections). The computer program product can be configured in an executable manner on a computer cloud in particular.

[0017] Likewise, the purpose outlined at the beginning is achieved by an evaluation unit according to the present invention. The evaluation unit has a memory and a computing unit and is suitable for storing and executing a computer program product thereon. The evaluation unit can be coupled at least to a flow measurement device and a vibration sensor. Alternatively, the evaluation unit can belong to the flow measurement device and can be coupled to the vibration sensor via a communication data link. According to the present invention, a computer program product is stored in an executable manner on the evaluation unit, and the computer program product is constructed according to one of the embodiments shown above. The computer program product claimed can also be quickly executed on hardware with relatively low computing performance. Therefore, the diagnostic method based on it can be implemented with the help of a simple and cost-effective evaluation unit.

[0018] Furthermore, the above-mentioned object is achieved by a flow measurement system according to the invention, which comprises a flow measurement device and a vibration sensor. The vibration sensor can be fixed directly to the pipeline in the region of the orifice plate, and the flow measurement device can be fixed indirectly via at least one effective pressure line. The flow measurement device and the vibration sensor are each connected via a communication data link to an evaluation unit, which also belongs to the flow measurement system. According to the invention, the evaluation unit is designed according to one of the above-mentioned embodiments.

[0019] Furthermore, the objects outlined at the outset are achieved by a simulation program product according to the invention. The simulation program product comprises instructions which, when executed on a computer, cause a simulation of the operating behavior of a flow measurement system. According to the invention, the flow measurement system is configured according to one of the above-described embodiments. The simulation program product is configured for use when simulating the operating behavior of a flow measurement system of a corresponding configuration.

[0020] The simulation program product can have a digital image of the flow measurement system, in which its structure is reproduced. In addition, the simulation program product can include a physical module, which is configured to simulate the operating behavior of the digital image under preset operating conditions. Belonging to the preset operating conditions can be the density, flow rate, viscosity and / or component of the fluid flowing through the pipeline fixed by the flow measurement system in the operation to be simulated or simulated. In particular, the contamination of the fluid by suspended matter will belong to one of the preset operating conditions, by which the effective pressure line will be blocked or blocked. The physical module can also be configured to simulate the flow behavior of the fluid at the orifice plate, in particular to simulate the formation of turbulence downstream of the orifice plate. The orifice plate can be rotationally symmetrically configured in the middle area. The present invention includes but is not limited to the following discovery: by simulating only the circumferential section of the orifice plate, due to the rotational symmetry of the orifice plate, a sufficiently accurate fluid dynamics simulation of the orifice plate can be achieved. Therefore, the computer program product can include a two-dimensional fluid simulation of the longitudinal section of the orifice plate or a three-dimensional fluid simulation of the circumferential section of the orifice plate. Thus, turbulence behind the orifice plate in relation to the flow direction can be simulated with relatively little computational effort. When executing the simulation program product, a two-dimensional or three-dimensional fluid simulation can be performed. Due to the reduced computational effort, the simulation program product can be constructed in a real-time capable manner. Starting from the turbulence, the vibrations triggered by the turbulence can be determined with the aid of reduced computational effort. This in turn enables a simplified simulation of the vibrations thus caused. When executing the simulation program product, vibrations can also be determined based on the turbulence determined by the two-dimensional or three-dimensional fluid simulation. Overall, a large number of such flow measurement systems can be realistically simulated with relatively little computational effort, which in turn allows, for example, precise monitoring at an automation system where the flow measurement system is used.

[0021] The simulation program product can be configured as a so-called digital twin, which is described in more detail, for example, in US2017 / 286572A1. The disclosure of US2017 / 286572A1 is incorporated into the present application by reference. The simulation program product can be configured to be used for: executing on a superior control unit and transmitting simulation results to a control program on a superior control unit. The control program can in turn intervene in the operation of the automation system based on the simulation results. The characteristics of the underlying diagnostic method and flow measurement system can be easily transferred to the simulation program product.

[0022] The above-mentioned purpose can also be achieved by the use of the vibration sensor according to the present invention. The vibration sensor is fixed to a pipeline, and an orifice plate is arranged in the pipeline. The orifice plate is configured to measure the flow rate of the fluid in the pipeline in cooperation with a flow measurement device. The vibration sensor is directly or indirectly fixed to the pipeline in the area of ​​the orifice plate and is configured to obtain the current vibration. According to the present invention, the vibration sensor is used to identify the blockage of the effective pressure line. The effective pressure line is configured to record the effective pressure in the area of ​​the orifice plate and obtain it in cooperation with the flow measurement device. The effective pressure obtained by means of the effective pressure line is used in the operation of the flow measurement device belonging to the flow measurement system to measure the flow rate in the pipeline.

[0023] The flow measurement system is designed in one of the embodiments outlined above. The features of the diagnostic method, the associated computer program product, the evaluation unit and the flow measurement system can be easily transferred to the claimed use. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The invention is explained in more detail below based on the embodiments in the drawings. The drawings should be understood as complementary to each other to the extent that the same reference numerals in different drawings have the same technical meaning. In addition, the features of the embodiments shown in the drawings can be combined with the features outlined above. It is shown in detail:

[0025] Figure 1 shows a schematic structure of the claimed flow measurement system in a stage of a first embodiment of the claimed diagnostic method;

[0026] Figure 2 A detailed view of the claimed flow measurement system is shown. DETAILED DESCRIPTION

[0027] exist Figure 1 The structure of the claimed flow measurement system 40 is schematically shown in FIG. Figure 1The first embodiment of the diagnostic method 100 shown in one of the stages of the flow measurement system 40 is performed at the flow system 40. The flow measurement system 40 comprises a flow measurement device 30, which is connected to the annular flange 14 via an effective pressure line 34. The first and second effective pressure lines 35, 36 are respectively designed to record the current first effective pressure or second effective pressure 23, 24 and transmit them hydraulically to the flow measurement device 30. The annular flange 14 connects the first and second pipes 11, 12, which belong to the pipeline 10, in which the flow velocity 19 of the fluid 13 flowing therein is measured. An orifice plate 16 is arranged between the first and second pipes 11, 12, and the fluid 13 can flow through the orifice plate. The orifice plate 16 has a substantially central opening 17, which is designed circumferentially, in particular circularly. The opening 17 is substantially centered on the pipe axis 18, along which the pipe 10 extends at least in sections, and the pipe axis defines the axial direction of the pipe. Along the flow direction 15 of the fluid 13 there is a region 28 of the orifice plate 16 in which fluid dynamic effects can be measurably present in a technically meaningful manner. In the region 28 of the orifice plate 16, a vibration sensor 20 is attached to the annular flange 14. The vibration sensor 20 is designed to detect vibrations 21 at the annular flange 14. The vibrations 21 are oriented essentially radially with respect to the pipe axis 18 and / or the flow direction 15. The vibration sensor 20 is connected to a flow measurement device 30 and is suitable for transmitting a measured value 25 of a vibration variable 22 to the flow measurement device 30. The vibration sensor 20 can be thermally insulated from the annular flange 14 by its fixing.

[0028] The flow measuring device 30 has a differential pressure measuring device 33, which is hydraulically connected to the effective pressure line 34, that is, to the first effective pressure line and the second effective pressure line 35, 36. The differential pressure device 33 is also designed to transmit at least one measured value 25 of the first effective pressure and / or the second effective pressure 24 to the evaluation unit 50. The differential pressure measuring device 33 is also designed to determine the pressure difference 37 between the first effective pressure and the second effective pressure 35, 36. The differential pressure 37 is a measure of the flow rate 19 in the fluid 13. The pressure measuring device 30 includes the evaluation unit 50. Alternatively, the evaluation unit 50 can also be designed separately from the pressure measuring device 30 and connected thereto. The evaluation unit 50 has a memory not shown in detail and a computing unit not shown in detail, which is designed to run a computer program thereon. In addition, the evaluation unit 30 is connected to the display device 38. In addition, the evaluation unit 50 and thus the evaluation unit 30 are connected to the superior control unit 60 via the data interface 32. Therefore, there is a communication data link between the evaluation unit 50 and the superior control unit 60. The superior control unit 60 also has a memory not shown in detail and a computing unit not shown in detail and is suitable for running a computer program on it. In addition, the superior control unit 60 is designed to output a control command 64, by means of which the automation system to which the pipeline 10 belongs can be controlled. The flow measurement system 40 is mapped in a simulation program product 65, which is designed to simulate the operating behavior of the flow measurement system 40. With the help of the simulation program product 100, it is possible to check the rationality of the diagnostic method 100, that is, the warning 39 output by it. For this purpose, the simulation program product 65 is designed as a digital twin of the flow measurement system 65. The simulation program product is executed on the superior control unit 60 and is designed to transmit the simulation result 66 to the control program 62 also executed on the superior control unit 60.

[0029] The diagnostic method 100 comprises a first step 110, in which a fluid 13 flows through the pipeline 10. During the first step 110, a first effective pressure 23 is detected. The first effective pressure 23 is detected by means of a flow measuring device 30. In addition, the diagnostic method 100 includes a second step 120, which can be performed simultaneously with the first step 110, before or after the first step. In the second step 120, at least one vibration variable 22 is detected by means of a vibration sensor 20. The vibration variable 22 is a measure of the intensity of the vibration 21 present in the region 28 of the orifice plate 16. The first and second steps 110, 120 are performed in a coordinated manner, so that the measured value 25 of the first effective pressure 23 and the measured value 25 of the vibration variable 22 belong to a common measurement point, i.e. are measured at substantially the same point in time.

[0030] Furthermore, a third step 130 is included in the diagnostic method 100, which can be performed after the first and second steps 110, 120 have been completed. In the third step 130, it is determined whether the magnitude of the first effective pressure 23 is below an adjustable first threshold value 26. Figure 1 The adjustable first threshold value 26 can be preset by a value table, user input, algorithm or artificial intelligence. Similarly, in the third step 130, it is determined whether the magnitude of the vibration variable 22 obtained in the second step 120 exceeds the adjustable second threshold value 27. The magnitude exceeds the adjustable threshold value 27 correspondingly. Figure 1 27. Similar to the first threshold value 26, the second threshold value 27 can be preset by a value table, user input, algorithm or artificial intelligence. If the magnitude of the first effective pressure 23 is below the adjustable first threshold value 26 and the magnitude of the vibration variable 22 exceeds the second threshold value 27, a blockage of the first effective pressure line 35 is detected in a third step 130.

[0031] A vibration variable 22 above the second threshold value 27 indicates that there is a flow through the orifice 16. The first effective pressure 23 indicates that, in the expected state of the first effective pressure line 35, the first effective pressure 23 detected above the orifice 16 is sufficiently high and exceeds the adjustable first threshold value 26. A blockage of the first effective pressure line 35 causes that the first effective pressure 23 cannot be detected by the flow measuring device 30. The vibration 21 detected by the vibration sensor 20 is caused by the flow through the orifice 16. The vibration variable 22 is a physical variable different from the first effective pressure 23, so that a diversified concept is realized by means of the vibration sensor 20 with the aid of the diagnostic method 100. If a blockage of the first effective pressure line 35 is detected, a corresponding warning 39 is output to the user via the display device 38. Likewise, the corresponding warning 39 is output to the superior control unit 60 via the data interface 32.

[0032] In addition, the diagnostic method 100 has a fourth step 140, which can be performed before, during or after the first, second and third steps 110, 120, 130. In the fourth step 140, measured values ​​25 of the vibration variable 22 and the first effective pressure 23 are acquired. The measured values ​​are used as training data to train the artificial intelligence 52. The artificial intelligence 52 is executed on the evaluation unit 50 and is suitable for cooperating with a computer program product 55 for implementing the diagnostic method 100. The computer program product 55 is also executed on the evaluation unit 50. In the fourth step 140, a reference state is determined by means of machine learning, which is suitable as a starting point for monitoring the wear behavior of the orifice plate 16. The reference state can exist, for example, immediately after the installation of a new orifice plate 16 and thus indicates a good state.

[0033] Furthermore, the diagnostic method 100 comprises a fifth step 150, in which the wear of the orifice plate 16 is detected by comparing the reference state determined in the fourth step 140 with the current first effective pressure 35, the current vibration variable 22 and / or a variable derived therefrom. Likewise, the fifth step 150 can be performed with the aid of the artificial intelligence 52. The fifth step 150 can be performed while the flow measurement system 40 is in operation.

[0034] Furthermore, the diagnostic method 100 comprises a sixth step 160, which is performed before, during or after the first, second, third, fourth or fifth step 110, 120, 130, 140, 150. In the sixth step 160, a first measured value 44 of the flow velocity 19 in the pipeline 10 is determined. The first measured value 44 of the flow velocity 19 is determined based on at least the first effective pressure 35 acquired in the first step 110. The first measured value 44 can in particular be determined based on the pressure difference 37, which in turn is determined starting from the first effective pressure and the second effective pressure 35, 36. Furthermore, the diagnostic method 100 has a seventh step 170, in which a second measured value 45 of the flow velocity 19 in the pipeline 10 is determined. The second measured value 45 is determined based on the vibration variable 22 acquired in the second step 120. The determination of the second measured value 45 of the flow velocity 19 can be performed, for example, by artificial intelligence. In the diagnostic method 100, the first measured value and the second measured value 44, 45 of the flow velocity 19 are further compared with each other. This comparison serves to check the plausibility of the first and second measured values ​​44, 45. The greater the difference between the first and second measured values ​​44, 45, the more likely it is that the vibration sensor 20, one of the effective pressure lines 34 or the flow measurement device 30, in particular the differential pressure measuring device 33, is in an incorrect state. Therefore, the operation of the flow measurement system 40 is monitored by means of the sixth and seventh steps 160, 170. The individual steps 110, 120, 130, 140, 150, 160, 170 are performed by a computer program product 55 executed on the evaluation unit 50. The diagnostic method 100 outlined for the first effective pressure 23 and the first effective pressure line 35 can also be performed for the second effective pressure 24 at the second effective pressure line 36 or a combination thereof.

[0035] exist Figure 2 The longitudinal section diagram schematically shows the Figure 1 A detailed view of the flow measurement system 40 is provided. The diagnostic method 100 is Figure 2The flow measurement system 40 is implemented in the flow measurement system 40. The fluid 13 flowing through the first tube 11 along the tube axis 18 in the flow direction 15 reaches the orifice plate 16, which is arranged between the first and second tubes 11, 12 in a manner fixed to the annular flange 14. The fluid 13 flows through the opening 17 in the orifice plate 16 and is accelerated there. The fluid 13 is delayed again behind the orifice plate 16 along the flow direction 15. As a result, the first effective pressure 23, 24 obtained before or after the orifice plate 16 have different values ​​and are a measure of the current flow rate 19. The orifice plate 16 has an edge 43 at the edge of its opening 17, which is worn due to the flow through the fluid 13. Turbulence 42 is caused by the edge 43 behind the orifice plate 16 along the flow direction 15. Turbulence 42 occurs periodically. When the turbulence 42 reaches the second pipe 12, i.e. its wall, it in turn causes vibrations 21, which are detected in the second step 120 of the diagnostic method 100 by means of the vibration sensor 20. The vibrations 21 caused by the turbulence 42 are also a measure of the flow velocity 19 in the pipeline 10. For the claimed diagnostic method 100, only a simple parameter indicating whether there is a flow through the orifice plate 16 is required by means of an adjustable second threshold value 27. When the flow measurement system 40 is commissioned, the second threshold value 27 can initially be adjusted, for example, by an estimated value, and can be adjusted more precisely in further operation. As a result, a blockage of the effective pressure line 34 can be detected sufficiently accurately, and at the same time there is a learning period in which a reference state of the orifice plate 16 can be determined.

[0036] The turbulence 42 occurring at the edge 43 of the opening 17 of the orifice plate 16 can be simulated in the simulation program product 65 with reduced computational effort. The opening 17 is designed substantially rotationally symmetrically with respect to the pipe axis 18. The fluid dynamic separation of the turbulence 42 at the edge 43 can therefore be shown in a two-dimensional fluid simulation. This two-dimensional fluid simulation requires reduced computational effort and can also be designed to have real-time capabilities. The simulation program product 65 configured as a digital twin thus has real-time capabilities and is thus suitable for monitoring the accompanying operation of the flow measurement system 40. Alternatively, the circumferential section of the orifice plate 16 in the region of the edge 43 can be simulated in a three-dimensional fluid simulation. Here, the circumferential section can have a size at which the separation of the turbulence 42 can also be simulated with reduced computational effort.

Claims

1. A diagnostic method (100) for a flow measurement system (40), the flow measurement system being attached to a pipe (10) through which flow can flow, the orifice plate (16) being arranged in the pipe, in, The flow measurement system (40) comprises a flow measurement device (30) connected to at least two effective pressure lines (34, 35, 36) arranged in the area (28) of the orifice plate (16) to obtain effective pressures (23, 24), and the diagnostic method comprises the following steps: a) passing a fluid (13) through the pipe (10) and obtaining the effective pressure (23, 24) in one of the effective pressure lines (34, 35, 36); Characterized in that the diagnostic method (100) further comprises the following steps: b) acquiring a vibration variable (22) of the vibration (21) via a vibration sensor (20) arranged in the region (28) of the orifice plate (16); c) if the magnitude of the effective pressure (23, 24) determined in step a) is below an adjustable first threshold value (26) and the magnitude of the vibration variable (22) determined in step b) is above an adjustable second threshold value (27), a blockage of the effective pressure line (34, 35, 36) is detected; If a blockage of the effective pressure line (34, 35, 36) is detected, a warning (39) is output to a user and / or a data interface (32).

2. The diagnostic method (100) according to claim 1, It is characterized in that The orifice plate (16) is attached to at least one annular flange (14) by which the first and second tubes (11, 12) of the pipeline (10) are connected to each other.

3. The diagnostic method (100) according to claim 1 or 2, It is characterized in that The vibration sensor (20) is attached at the pipe (10) or at the annular flange (14).

4. The diagnostic method (100) according to any one of claims 1 to 3, It is characterized in that The diagnostic method (100) further comprises the following steps: d) training an artificial intelligence (52) and determining a reference state of the orifice plate (16) based on the measured values ​​(25) of the effective pressure (23, 24) and at least one vibration variable (22); e) detecting wear of the orifice plate (16) by comparing the reference state with a current effective pressure (23, 24), at least one current vibration variable (22) and / or a variable derived from the current effective pressure and / or the current vibration variable.

5. The diagnostic method (100) according to any one of claims 1 to 4, It is characterized in that The flow measurement device (30) is designed as a differential pressure measurement device (33).

6. The diagnostic method (100) according to any one of claims 1 to 5, It is characterized in that At least one of the effective pressure lines (34, 35, 36) has a length of 1 m to 20 m.

7. The diagnostic method (100) according to any one of claims 1 to 6, It is characterized in that The vibrations (21) detected by the vibration sensor (20) are oriented perpendicularly to the axial direction of the pipeline (10).

8. The diagnostic method (100) according to any one of claims 1 to 7, It is characterized in that The diagnostic method (100) further comprises the following steps: f) determining a first measured value (44) of the flow velocity (19) in the pipeline (10) based on at least the effective pressure (23, 24) obtained in step a); g) determining a second measured value (45) of the flow velocity (19) in the pipeline (10) based on the vibration variable (22) obtained in step b); Therein, the first measured value and the second measured value (44, 45) are compared with one another for plausibility checking.

9. A computer program product (55) designed to receive and process measured values ​​(25) of an effective pressure (23, 24) and of at least one vibration variable (22), It is characterized in that The computer program product (55) is designed to perform at least one of the diagnostic methods (100) according to any one of claims 1 to 8 on a flow measurement system (40) attached to a flow-permeable pipeline (10), an orifice plate (16) being arranged in the pipeline, and the flow measurement system comprises a flow measurement device (30) having at least two effective pressure lines (34, 35, 36), a vibration sensor (20), and the flow measurement system comprises a data interface (32) for outputting a warning (39).

10. An evaluation unit (50) designed to store and execute a computer program product (55), and designed to be coupled to a flow measuring device (30) and a vibration sensor (20) via at least one communication data link, It is characterized in that The computer program product (55) is designed according to claim 9.

11. A flow measurement system (40) comprising a flow measurement device (30) and a vibration sensor (20), which can be attached to a pipeline (10) in the region (28) of an orifice plate (16) and are connected to an evaluation unit (50) via at least one communication data link, It is characterized in that The evaluation unit (50) is designed according to claim 10.

12. A simulation program product (65) comprising instructions which, when executed on a computer, cause the computer to simulate the operating behavior of a flow measurement system (40), It is characterized in that The flow measurement system (40) is designed according to claim 11.

13. Use of a vibration sensor (20) attached to a pipeline (10) in the region (28) of an orifice plate (16) to acquire current vibrations (21) at the pipeline, It is characterized in that The vibration sensor (20) is used to detect blockage of an effective pressure line (34, 35, 36), by means of which an effective pressure (23, 24) is acquired in the area (28) of the orifice plate (16) to measure the flow rate (19) in the pipeline (10), and the vibration sensor (20) is used in a flow measurement system (40) according to claim 11.

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