JP2015197323A - Correction value determination device and correction value determination method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To readily perform the correction of the flow rate of a measurement target fluid, thereby accurately measuring the flow rate of the measurement target fluid.SOLUTION: A correction value determination device comprises: a thermal flow sensor that is placed in a pipe through which a measurement target fluid flows and measures a first flow rate of the measurement target fluid; a vortex flowmeter that is placed in the pipe and measures a second flow rate of the measurement target fluid; a flow rate comparison unit that performs the comparison between the measured first flow rate and the measured second flow rate; and a correction value determination unit that determines a correction value for correcting the first flow rate on the basis of the results of the comparison.

Description

  The present invention relates to a correction value determination device and a correction value determination method.

  Conventionally, a vortex flowmeter or a thermal flowmeter is used to measure the flow rate of the fluid to be measured flowing through the pipe.

  For example, Patent Document 1 discloses a composite flow meter including a Karman vortex flow meter that measures a flow rate in a high flow rate region and a thermal flow meter that enables measurement from a low flow rate range.

  Further, according to Patent Document 2 that discloses a multi-vortex flow meter composed of a vortex detection means and a thermal detection means, the vortex detection means is not suitable for low flow measurement, and the thermal detection means is It is known that it is not suitable for high flow measurement.

JP-A-2-161313 JP 2006-029966 A

  By the way, if there is a difference between the composition of the measurement fluid used when adjusting the thermal flow meter at the time of shipment and the composition of the fluid actually flowing after the thermal flow meter is installed, the output of the thermal flow meter An error occurs. The reason is that the thermal conductivity and the like differ depending on the change in the composition of the fluid. Especially in overseas countries, the composition of fluid used in each country and region is different, and even in the case of fluids used in Japan, the composition of fluid varies depending on the region and gas company. Is the actual situation.

  In order to accurately measure the flow rate of the fluid, it is necessary to manually set in advance a correction value (conversion factor) for correcting the output characteristics of the thermal flow meter in accordance with the composition of the fluid. For example, when the fluid composition changes as described above, it is necessary for the operator to manually input the conversion factor each time in the field according to the change in the fluid composition to correct the output characteristics of the thermal flow meter. There was, and it took time and effort.

  Furthermore, the thermal flow meter described in Patent Document 1 and the thermal detection means described in Patent Document 2 can measure the flow rate of fluid with high accuracy from a low flow rate range. The measurement accuracy is easily affected by the composition change and the like, and there is a possibility that the measurement flow rate value is shifted. Further, there is no means for calibrating the deviation of the measured flow rate values of the thermal flow meter and the thermal detection means, and there is a possibility that the measurement of the flow rate is performed as it is and an inaccurate measurement value is output.

  Therefore, the present invention can easily correct the flow rate of the target measurement fluid, and can be one of the purposes to accurately measure the flow rate of the measurement target fluid.

  The present inventor actually uses a thermal flow sensor that can accurately measure the flow rate Q1 of the measurement target fluid from a low flow rate range and a vortex flow meter that can accurately measure the flow rate Q2 of the measurement target fluid at a high flow rate range. As a result of measuring the flow rate of the fluid to be measured and rigorously verifying the measurement results, (1) the vortex flow meter is resistant to dirt and is not affected by changes in the composition of the fluid; There is an overlapping flow area between the measured flow area where Q1 was measured and the measured flow area where the vortex flowmeter measured flow Q2, and the measured values of the thermal flow sensor and vortex flowmeter in this overlapping flow area In any case, it is possible to determine deterioration (abnormality) in measurement accuracy due to contamination, fluid composition change, or the like, and to calibrate the other measurement value with one measurement value. Therefore, in the overlapping flow rate range, a vortex flow meter that can measure the flow rate more accurately without being affected by changes in the fluid composition measures the fluid flow rate Q2, and a thermal flow sensor measures the fluid flow rate Q1. Then, the flow rate Q2 is used as a reference flow rate, the flow rate Q2 is compared with the flow rate Q1, and a correction value (conversion factor) for correcting the measured flow rate of the thermal flow sensor is determined based on the comparison result. The measured flow rate was corrected based on the correction value.

  In order to solve the above problems, a correction value determination device according to one aspect of the present invention is installed in a pipe through which a measurement target fluid is circulated, and a thermal flow sensor that measures a first flow rate of the measurement target fluid; A vortex flow meter installed in a pipe for measuring the second flow rate of the fluid to be measured, a flow rate comparison unit for comparing the measured first flow rate with the second flow rate, and a result of the comparison And a correction value determining unit that determines a correction value for correcting the first flow rate.

  In order to solve the above problem, a correction value determination method according to one aspect of the present invention measures a first flow rate of the measurement target fluid by a thermal flow sensor installed in a pipe through which the measurement target fluid is circulated. The second flow rate of the fluid is measured by a vortex flow meter installed in the pipe, the measured first flow rate and the second flow rate are compared, and based on the result of the comparison, A correction value for correcting the first flow rate is determined.

  According to the present invention, the correction value for performing the comparison between the measurement flow rate of the thermal flow sensor and the measurement flow rate of the vortex flow meter and correcting the measurement flow rate of the thermal flow sensor based on the comparison result. Automatically determining the measurement flow rate based on the correction value, so that the flow rate of the target measurement fluid can be easily corrected and the flow rate of the measurement target fluid can be accurately measured. Can be connected to

It is side surface sectional drawing which shows the structure of the correction value determination apparatus which concerns on 1st Embodiment of this invention. It is a plane sectional view showing composition of a correction value deciding device concerning a 1st embodiment of the present invention. It is a block diagram which shows the functional structure of the correction value determination apparatus which concerns on 1st Embodiment of this invention. It is a flowchart for correct | amending the flow volume of the measurement object fluid which the thermal flow sensor of the correction value determination apparatus which concerns on 1st Embodiment of this invention measures. It is side surface sectional drawing which shows the structure of the correction value determination apparatus which concerns on 2nd Embodiment of this invention. It is a plane sectional view showing composition of a correction value deciding device concerning a 2nd embodiment of the present invention. It is a block diagram which shows the functional structure of the correction value determination apparatus which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the functional structure of the vortex flow meter which concerns on 2nd Embodiment of this invention. It is a flowchart for correct | amending the flow volume of the measuring object fluid which the thermal flow sensor of the correction value determination apparatus which concerns on 2nd Embodiment of this invention measures.

  Embodiments of the present invention will be described below with reference to the drawings. However, the embodiment described below is merely an example, and there is no intention to exclude various modifications and technical applications that are not explicitly described below. That is, the present invention can be implemented with various modifications (combining the embodiments) without departing from the spirit of the present invention. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. The drawings are schematic and do not necessarily match actual dimensions and ratios. In some cases, the dimensional relationships and ratios may be different between the drawings.

(First embodiment)
1 to 4 show a first embodiment of the present invention. FIG. 1 is a side sectional view showing a configuration of a correction value determining apparatus 1 according to the first embodiment of the present invention. FIG. 2 is a plan sectional view showing the configuration of the correction value determining apparatus 1 according to the first embodiment of the present invention. FIG. 3 is a block diagram showing a functional configuration of the correction value determining apparatus 1 according to the first embodiment of the present invention.

  As shown in FIGS. 1 and 2, the correction value determination device 1 according to the present embodiment exemplarily flows a measurement target fluid such as gas (hereinafter simply referred to as “fluid”) in a direction indicated by an arrow. A pipe 12, a rectifying mechanism 14, a thermal flow sensor 16, and a vortex flow meter 20 are provided. The vortex flow meter 20 includes a vortex generator 21, a vortex flow sensor 22, a pressure sensor 24, a temperature sensor 26, and the control means not shown in FIGS. 1 and 2 but shown in FIG. 3. 40.

  Here, the correction value determination device 1 is illustratively composed of a vortex flow meter 20 and a thermal flow meter.

  An inlet 30 is provided at the upstream end of the fluid flow of the pipe 12, and a discharge port 32 is provided at the downstream end. The inlet 30 and the discharge port 32 are attached to each. Connected to other piping (not shown).

  The rectifying mechanism 14 is disposed in the pipe 12 and has a function of adjusting the flow of fluid. The rectifying mechanism 14 eliminates or reduces the swirling flow, drift, etc. of the fluid, and reduces the adverse effect on the characteristics of the various flow meters, upstream of the various sensors and flow meters (lower side in FIGS. 1 and 2). Installed. Examples of the rectifying mechanism 14 include a rectifying mechanism such as a perforated plate type, a tubular type, a Ben type, a mechanism using a wire net or a honeycomb.

  The thermal flow sensor 16 is installed in the pipe 12 through which the fluid flows, and measures the mass flow rate of the fluid. In the present embodiment, the flow rate of the fluid measured by the thermal flow sensor 16 will be described below as an average flow rate obtained by averaging the instantaneous flow rates in a predetermined flow rate measurement period. However, the present invention is not limited to this. Other flow rates such as an instantaneous flow rate may be adopted.

  The vortex flow meter 20 is installed in the pipe 12 through which the fluid flows, and measures the mass flow rate of the fluid. Specifically, the vortex flow meter 20 is configured such that the volume flow rate detected by the vortex flow sensor 22 is described below, the cross-sectional area of the vortex generator 22, the fluid pressure and temperature measured by the pressure sensor 24. The mass flow rate of the fluid is measured based on the temperature of the fluid measured by the sensor 26. Further, in the present embodiment, the flow rate of the fluid measured by the vortex flow meter 20 will be described below as an average flow rate obtained by averaging the instantaneous flow rates in a predetermined flow rate measurement period. Other flow rates such as an instantaneous flow rate may be adopted. The vortex flow meter 20 can employ various methods capable of measuring the flow rate of the fluid, and is not limited to the above method.

  The vortex generator 21 is one of the elements constituting the vortex flow meter 20. As shown in FIG. 1, the vortex generator 21 is a columnar member, and is installed in the pipe 12 so as to cross the radial direction thereof. The vortex generator 21 configured as described above generates vortices in the fluid flowing through the pipe 12. The shape of the vortex generator 21 may be any shape as long as it can generate a vortex in the fluid, and may have a triangular prism shape, a cylindrical shape, or the like.

  Each of the vortex flow sensor 22, the pressure sensor 24, and the temperature sensor 26 is one of the elements constituting the vortex flow meter 20. The vortex flow sensor 22 measures the volume flow rate of the fluid flowing through the pipe 12. The pressure sensor 24 measures the pressure of the fluid flowing through the pipe 12. The temperature sensor 26 measures the temperature of the fluid flowing through the pipe 12.

  As for the positional relationship between the thermal flow sensor 16 and the vortex flow meter 20 installed in the pipe 12, the vortex flow meter 20 is located downstream of the thermal flow sensor 16 in the pipe 12 (in FIGS. 1 and 2). , Upper side). Thereby, even if a vortex is generated in the fluid by the vortex generator 21 of the vortex flow meter 20, the vortex is generated further downstream in the pipe 12 than the thermal flow sensor 16. Therefore, the generation of vortices does not adversely affect the fluid flow measurement of the thermal flow sensor 16, and the thermal flow sensor 16 can accurately measure the fluid flow.

  The control means 40 shown in FIG. 3 functionally includes a storage unit 41, a flow rate determination unit 42, a flow rate comparison unit 43, a correction value determination unit 44, a flow rate correction unit 45, an output unit 46, and an input unit 47. Has been.

  The control means 40 is based on the fluid mass flow rate (first flow rate) measured by the thermal flow sensor 16 and the fluid mass flow rate (second flow rate) measured by the vortex flow meter 20. 16 measured flow rates are corrected.

  As will be described later, the storage unit 41 executes a difference between the mass flow rate of the fluid measured by the thermal flow sensor 16 and the mass flow rate of the fluid measured by the vortex flow meter 20 executed by the flow rate comparison unit 43, and a predetermined amount. The predetermined threshold value used in comparison with the threshold value, information indicating the measurable range of the mass flow rate of the fluid measured by the thermal flow sensor 16, and the measurement of the mass flow rate of the fluid measured by the vortex flow meter 20 It is a functional block that stores information indicating a possible range. Further, a correction value (conversion factor) for correcting the first flow rate of the thermal flow sensor 16, which will be described later, and the difference between the measured flow rate of the thermal flow sensor 16 and the measured flow rate of the vortex flow meter 20, A relational expression or relation table indicating the relation is stored. The storage unit 41 can input and output the threshold value and information. In addition to the above, the storage unit 41 has information indicating a flow rate range where the measurement accuracy of the mass flow rate of the fluid measured by the thermal flow sensor 16 is high, and the measurement accuracy of the mass flow rate of the fluid measured by the vortex flow sensor 20. Information indicating a high flow rate range may be stored. In this case, the storage unit 41 outputs the above information when needed by the flow rate determination unit 42 described later.

  The flow rate determination unit 42 is a functional block that determines whether or not the flow rate of the fluid is within a range in which the mass flow rate (second flow rate) of the fluid measured by the vortex flow meter 20 can be measured. Specifically, the flow rate determination unit 42 measures the vortex flow meter 20 based on the information stored in the storage unit 41 and indicating the measurable range of the mass flow rate of the fluid measured by the vortex flow meter 20. It is determined whether the mass flow rate of the fluid to be measured is within a measurable range. The flow rate determination unit 42 is a functional block that determines whether or not the flow rate of the fluid is within a range in which the mass flow rate (first flow rate) of the fluid measured by the thermal flow sensor 16 can be measured. Specifically, the flow rate determination unit 42 measures the thermal flow rate sensor 16 based on information stored in the storage unit 41 and indicating the measurable range of the mass flow rate of the fluid measured by the thermal flow rate sensor 16. It is determined whether the mass flow rate of the fluid to be measured is within a measurable range.

  Further, as described above, the vortex flow meter 20 is resistant to dirt and the like. In addition, there is an overlapping flow rate region between the measured flow rate region where the thermal flow sensor 16 measures the flow rate Q1 and the measured flow rate region where the vortex flow meter 20 measures the flow rate Q2. Therefore, in the overlapping flow rate range, the vortex flow meter 20 that is resistant to dirt and can measure the flow rate more accurately measures the flow rate Q2 of the fluid, and the thermal flow rate sensor 16 measures the flow rate Q1 of the fluid. As will be described later, the flow rate comparison unit 43 compares the flow rate Q2 with the flow rate Q1 using the flow rate Q2 as a reference flow rate. As described above, in order to set the flow rate Q2 as the reference flow rate, the flow rate determination unit 42 is at least within a range in which the mass flow rate (second flow rate) of the fluid measured by the vortex flow meter 20 can be measured. Judge whether or not. The flow rate determination unit 42 also determines whether the mass flow rate (first flow rate) of the fluid measured by the thermal flow sensor 16 is within a measurable range before and after the determination. Identify overlapping areas. That is, the flow rate determination unit 42 determines whether or not the flow rate of the measurement target fluid is within a range in which both the thermal flow sensor 16 and the vortex flow meter 20 can be measured.

  The flow rate comparison unit 43 performs a comparison between the mass flow rate (first flow rate) of the fluid measured by the thermal flow sensor 16 and the mass flow rate (second flow rate) of the fluid measured by the vortex flow meter 20. It is a block. Specifically, the flow rate comparison unit 43 determines the difference between the first flow rate and the second flow rate when the flow rate of the measurement target fluid is within a range in which both the thermal flow sensor 16 and the vortex flow meter 20 can be measured. Determines whether or not a predetermined threshold stored in the storage unit 41 has been exceeded. More specifically, the flow rate comparison unit 43 uses the measured mass flow rate of the vortex flow meter 20 in the overlapping region as a reference flow rate, and the measured mass flow rate of the thermal flow sensor 16 and the measured mass flow rate of the vortex flow meter 20 Further, the difference between the measured mass flow rate of the thermal flow sensor 16 and the measured mass flow rate of the vortex flow meter 20 is compared with the predetermined threshold value.

  The correction value determination unit 44 is based on the result of comparison between the measured mass flow rate (first flow rate) of the thermal flow sensor 16 and the measured mass flow rate (second flow rate) of the vortex flow meter 20 executed by the flow rate comparison unit 43. And a functional block for determining a correction value (conversion factor) for correcting the first flow rate. Specifically, the correction value determination unit 44 corrects the first flow rate of the thermal flow sensor 16 stored in the storage unit 41, the measured flow rate of the thermal flow sensor 16, and the vortex flow meter. The first flow rate of the thermal flow rate sensor 16 is corrected according to the difference between the first flow rate and the second flow rate by referring to a relational expression or a relation table showing a relation between the difference from the measured flow rate of 20. Determine the correction value.

  The flow rate correction unit 45 is a functional block that corrects the measured mass flow rate (first flow rate) of the thermal flow sensor 16 based on the correction value (conversion factor) determined by the correction value determination unit 44. Specifically, the mass flow rate after correction (first flow rate) of the thermal flow sensor 16 corrected by the correction value determined by the correction value determination unit 44 is measured by the thermal flow sensor 16 ( (Third flow rate).

  The output unit 46 is a functional block that outputs images, sounds, and the like. Specifically, it is a functional block that executes display of the operation screen of the correction value determination device 1 and notification of a correction result when the correction value determination device 1 completes correction of the measured flow rate of the thermal flow sensor 16. As the output unit 46, an image display device such as a liquid crystal display or an organic EL display, a printer, or the like can be employed.

  The input unit 47 is a functional block for inputting user operation information and the like. For example, a computer capable of inputting information such as operation buttons, a keyboard, and a mouse can be employed. Note that the output unit 46 may have the function of the input unit 47. For example, when the output unit 47 is an image display device having a touch panel, the user can supply operation information to the output unit 46 using the touch panel.

  FIG. 4 is a flowchart for correcting the flow rate of the fluid to be measured, which is measured by the thermal flow sensor 16 of the correction value determination device 1 according to the first embodiment of the present invention.

  First, in step S1, the vortex flow meter 20 measures the average flow rate Q2.

  Next, in step S2, the flow rate determination unit 42 of the control means 40 determines whether or not the average flow rate Q2 measured by the vortex flow meter 20 is within the measurable flow rate range.

  When the flow rate determination unit 42 determines that the average flow rate Q2 is not within the measurable flow rate range, the process of correcting the measured flow rate of the thermal flow sensor 16 ends.

  When the flow rate determination unit 42 determines that the average flow rate Q2 is within the measurable flow rate range, the process proceeds to step S3. In step S3, the thermal flow sensor 16 measures the average flow Q1.

  In step S4, the vortex flow meter 20 measures the average flow rate Q2.

  In step S <b> 5, the flow rate comparison unit 43 compares the average flow rate Q <b> 1 measured by the thermal flow sensor 16 with the average flow rate Q <b> 2 measured by the vortex flow meter 20.

  In step S6, the flow rate comparison unit 43 determines whether or not the difference between the average flow rate Q1 measured by the thermal flow sensor 16 and the average flow rate Q2 measured by the vortex flow meter 20 is greater than a predetermined threshold value.

  When the flow rate comparison unit 43 determines that the difference between the average flow rate Q1 and the average flow rate Q2 is not greater than a predetermined threshold, the process of correcting the measured flow rate of the thermal flow sensor 16 ends.

  When the flow rate comparison unit 43 determines that the difference between the average flow rate Q1 and the average flow rate Q2 is greater than a predetermined threshold value, the process proceeds to step S7. In step S7, the correction value determining unit 44 determines a correction value for correcting the average flow rate Q1.

  In step S8, the flow rate correction unit 45 corrects the average flow rate Q1 based on the determined correction value.

  According to the embodiment described above, the flow rate of the target measurement fluid can be easily corrected, and the flow rate of the measurement target fluid can be accurately measured.

(Second Embodiment)
5 to 9 are for illustrating a second embodiment of the present invention. Unless otherwise specified, the same components as those of the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 5 is a side sectional view showing the configuration of the correction value determining apparatus 2 according to the second embodiment of the present invention. FIG. 6 is a plan cross-sectional view showing the configuration of the correction value determining apparatus 2 according to the second embodiment of the present invention. FIG. 7 is a block diagram showing a functional configuration of the correction value determining apparatus 2 according to the second embodiment of the present invention.

  As shown in FIGS. 5 and 6, the thermal flow meter 2 according to the present embodiment exemplarily includes a pipe 12, a rectifying mechanism 14, a thermal flow sensor 16, a flow meter member 100, and an attachment / detachment mechanism. 110a and 110b, and control means 50 shown in FIG. 3 (not shown in FIGS. 1 and 2).

  The flow meter member 100 includes a vortex flow meter 120. The vortex flow meter 20 includes, for example, a vortex generator 21, a vortex flow sensor 22, a pressure sensor 24, and a temperature sensor 26. It is prepared for.

  The flow meter member 100 includes the vortex flow meter 120 as described above, and is configured to be detachable from the pipe 12. The flow meter member 100 only needs to be configured to be detachable from the pipe 12, and the material and structure of the member are not particularly limited. In addition, the pipe 12 includes attachment / detachment mechanisms 110a and 110b for detachably attaching the flow meter member 100 to the pipe 12. The attachment / detachment mechanisms 110a and 110b are illustratively provided with a locking recess, a fixing / supporting member for fixing / supporting the flowmeter member 100 to the pipe 12, and a fluid in order to improve the sealing performance in the pipe 12 and the flowmeter member 100. In order to prevent leakage to the outside, a sealing member or the like is provided. The attachment / detachment mechanisms 110a and 110b are configured to be able to perform positioning of the vortex flow meter 20 with respect to the pipe 12. The attachment / detachment mechanisms 110a and 110b are configured to be able to adjust and determine the position of the vortex flow meter 120 in the pipe 12 when or after the flow meter member 100 is attached to the pipe 12. The attachment / detachment mechanism 110a, b of the flow meter member 100 and the pipe 12 attaches / detaches at least one vortex generator 21, vortex flow sensor 22, pressure sensor 24, and temperature sensor 26 constituting the vortex flow meter 20. It may be configured to be possible.

  The vortex flow meter 120 is attached to the pipe 12 via the flow meter member 100 and measures the mass flow rate (second flow rate) of the fluid. Specifically, the vortex flow meter 20 is configured to measure the volume flow rate of the fluid detected by the vortex flow rate sensor 22, the volume flow rate, the cross-sectional area of the vortex generator 22 described later, and the fluid flow rate measured by the pressure sensor 24. Based on the pressure and the temperature of the fluid measured by the temperature sensor 26, the mass flow rate of the fluid is measured. In the present embodiment, the flow rate of the fluid measured by the vortex flow meter 120 will be described below as an average flow rate obtained by averaging the instantaneous flow rates in a predetermined flow rate measurement period. Other flow rates such as an instantaneous flow rate may be adopted. The vortex flow meter 120 can employ various methods capable of measuring the mass flow rate of the fluid, and is not limited to the above method.

  In addition, regarding the positional relationship between the thermal flow sensor 16 and the flow meter member 100 (vortex flow meter 120) installed in the pipe 12, the flow meter member 100 is located downstream of the thermal flow sensor 16 in the pipe 12 ( In FIG. 5 and FIG. Thus, even if a vortex is generated in the fluid by the vortex generator 21 of the vortex flow meter 120, the vortex is generated further downstream in the pipe 12 than in the thermal flow sensor 16. Therefore, the generation of vortices does not adversely affect the fluid flow measurement of the thermal flow sensor 16, and the thermal flow sensor 16 can accurately measure the fluid flow.

  The control means 50 of the correction value determination device 2 shown in FIG. 7 functionally includes a storage unit 51, a flow rate determination unit 52, a correction value determination unit 53, a flow rate correction unit 54, an output unit 46, and an input unit 47. It is configured.

  The control means 50 is a thermal flow sensor based on the fluid mass flow rate (first flow rate) measured by the thermal flow sensor 16 and the fluid mass flow rate (second flow rate) measured by the vortex flow meter 120. Sixteen measured flow rates are corrected.

  As will be described later, the storage unit 51 uses a correction value for the measured flow rate (first flow rate) of the thermal flow sensor 16 used by the flow rate correction unit 54 to correct the measured flow rate of the thermal flow sensor 16. Stores a relational expression or a relation table showing the relation between (conversion factor) and the difference between the measured flow rate (first flow rate) of the thermal flow sensor 16 and the measured flow rate (second flow rate) of the vortex flow meter 120. Function block. The storage unit 51 is a functional block that stores information indicating the measurable range of the mass flow rate of the fluid measured by the thermal flow sensor 16. The storage unit 51 can input / output at least one of the correction value and the information. In addition to the above, the storage unit 51 may store information indicating a flow rate range where the measurement accuracy of the mass flow rate of the fluid measured by the thermal flow sensor 16 is high. In this case, the storage unit 51 outputs the above information when needed by the flow rate determination unit 52 described later.

  The flow rate determination unit 52 is a functional block that determines whether the fluid flow rate is within a range that can be measured by the thermal flow sensor 16. Specifically, the flow rate determination unit 43 is based on the information stored in the storage unit 41 and indicating the range in which the thermal flow rate sensor 16 can measure the mass flow rate of the fluid. Determine whether the mass flow rate is within a measurable range.

  As will be described later, the correction value determination unit 53 includes a measurement mass flow rate (first flow rate) of the thermal flow sensor 16 and a measurement mass flow rate of the vortex flow meter 20 (first flow rate) executed by the flow rate comparison unit 65 of the vortex flow meter 120. This is a functional block for determining a correction value (conversion factor) for correcting the first flow rate based on the result of comparison with the second flow rate). Specifically, as will be described later, the correction value determining unit 53 receives the measured mass flow rate and the vortex flow rate of the thermal flow sensor 16 executed by the flow rate comparison unit 65 from the flow rate comparison unit 65 of the vortex flow meter 120. The result of the comparison with the measured mass flow rate of the total 20 is received. The correction value determination unit 53 then determines the thermal flow sensor 16 according to the difference between the measured mass flow rate (first flow rate) of the thermal flow sensor 16 and the measured mass flow rate (second flow rate) of the vortex flow meter 20. A correction value for correcting the first flow rate is determined. More specifically, the correction value determination unit 53 corrects the first flow rate of the thermal flow sensor 16 stored in the storage unit 51, the measured flow rate and the vortex flow rate of the thermal flow sensor 16. The first flow rate of the thermal flow sensor 16 is corrected according to the difference between the first flow rate and the second flow rate by referring to a relational expression or a relation table showing a relation between the difference from the measured flow rate of the meter 120. A correction value to be determined is determined.

  The flow rate correction unit 54 is a functional block that corrects the measured mass flow rate (first flow rate) of the thermal flow sensor 16. Specifically, based on the correction value (conversion factor) for correcting the measured mass flow rate (first flow rate) of the thermal flow sensor 16 determined by the correction value determination unit 53, The measured mass flow rate (first flow rate) is corrected. More specifically, the corrected mass flow rate by which the thermal flow sensor 16 measures the measured mass flow rate (first flow rate) of the thermal flow sensor 16 that is corrected with the correction value determined by the correction value determination unit 53. Output as (third flow rate).

  Note that the flow rate correction unit 54 may correct the measurement flow rate of the thermal flow sensor 16 a plurality of times. Specifically, first, the flow rate comparison unit 65 of the vortex flow meter 120 compares the measured flow rates measured by the thermal flow sensor 16 and the vortex flow meter 120 in any given measurement time zone. Further, the flow rate comparing unit 65 compares the measured flow rates in the same time zone measured by the thermal flow sensor 16 and the vortex flow meter 120 in a measurement time zone different from the above. In this way, the flow rate comparison unit 65 repeats the comparison a plurality of times. Then, the flow rate correction unit 54 corrects the measured flow rate of the thermal flow sensor 16 based on each of the results of multiple comparisons performed by the flow rate comparison unit 65 of the vortex flow meter 120.

  FIG. 8 is a block diagram showing a functional configuration of the vortex flow meter 120 according to the second embodiment of the present invention. As shown in FIG. 8, the vortex flow meter 120 functionally includes a control means 60, a vortex flow sensor 22, a pressure sensor 24, and a temperature sensor 26. The control means 60 is functionally configured to include a storage unit 61, a flow rate determination unit 63, a flow rate comparison unit 65, an input unit 66, and an input unit 67.

  The control means 60 executes a comparison between the mass flow rate (first flow rate) of the fluid measured by the thermal flow sensor 16 and the mass flow rate (second flow rate) of the fluid measured by the vortex flow meter 20. is there.

  As will be described later, the storage unit 61 compares the difference between the mass flow rate of the fluid measured by the thermal flow sensor 16 and the mass flow rate of the fluid measured by the vortex flow meter 20, which is executed by the flow rate comparison unit 65. It is a functional block that stores information indicating a predetermined threshold used and a range in which the vortex flow meter 120 can measure the mass flow rate of the fluid. The storage unit 61 can input and output at least one of the threshold value and the information. In addition to the above information, the storage unit 61 may store information indicating a flow rate range where the measurement accuracy of the mass flow rate of the fluid measured by the vortex flow meter 20 is high. In this case, the storage unit 61 outputs the above information when needed by the flow rate determination unit 63 described later.

  The flow rate determination unit 63 is a functional block that determines whether the flow rate of the fluid is within a range that can be measured by the vortex flow meter 120 of the flow meter member 100 attached to the pipe 12. Specifically, the flow rate determination unit 63 determines whether the vortex flow meter 120 is in a fluid flow based on information indicating a range in which the vortex flow meter 120 can measure the mass flow rate of the fluid. Determine whether the mass flow rate is within a measurable range.

  Further, as described above, the vortex flow meter 120 is resistant to dirt and is not affected by a change in the composition of the fluid. In addition, there is an overlapping flow rate range between the flow rate range that the thermal flow sensor 16 can measure and the flow rate range that the vortex flow meter 120 can measure. Therefore, in the present embodiment, in the overlapping flow range, the dirt is resistant to dirt and is not affected by the change in the composition of the fluid, and the dirt is based on the measurement value of the vortex flow meter 120 that can measure the fluid flow rate more accurately. The measurement flow rate of the thermal flow sensor 16 that is affected by the change in the composition of the fluid or the fluid and that causes a deviation in the measurement flow rate is corrected. That is, the vortex flow meter 120 measures the fluid flow rate Q2, and the thermal flow sensor 16 measures the fluid flow rate Q1. Then, the flow rate comparison unit 65 compares the flow rate Q2 with the flow rate Q1 using the flow rate Q2 as a reference flow rate. As described above, in order to set the flow rate Q2 as the reference flow rate, the flow rate determination unit 63 is at least within a range in which the mass flow rate (second flow rate) of the fluid measured by the vortex flow meter 120 can be measured. Judge whether or not. Then, the flow rate determination unit 63 also determines whether the mass flow rate (first flow rate) of the fluid measured by the thermal flow sensor 16 is within a measurable range before and after the determination. Identify overlapping areas.

  The flow rate comparison unit 65 receives the mass flow rate (first flow rate) of the fluid measured by the thermal flow sensor 16, and the vortex flow meter 120 of the flow meter member 100 attached to the first flow rate and the pipe 12. It is a functional block which performs comparison with the mass flow rate (2nd flow rate) of the measured fluid. Specifically, the flow rate comparing unit 65 determines that the first flow rate is determined when the flow rate determining unit 63 determines that the flow rate of the fluid is within a range in which both the thermal flow sensor 16 and the vortex flow meter 120 can be measured. It is determined whether or not the difference between the flow rate and the second flow rate exceeds a predetermined threshold value stored in the storage unit 61. More specifically, the flow rate comparison unit 65 uses the measured mass flow rate of the vortex flow meter 120 in the overlapping region as a reference flow rate, and the measured mass flow rate of the thermal flow sensor 16 and the measured mass flow rate of the vortex flow meter 120 Further, the difference between the measured mass flow rate of the thermal flow sensor 16 and the measured mass flow rate of the vortex flow meter 120 is compared with the predetermined threshold value. Furthermore, the flow rate comparison unit 65 transmits the result of the comparison to the flow rate correction unit 45 of the thermal flow meter.

  The output unit 66 is a functional block that outputs images and sounds. Specifically, it is a functional block that executes display of an operation screen of the vortex flow meter 120, notification of a result of comparison of measured flow rates performed by the flow rate comparison unit 65, and the like. In addition, as will be described later, the output unit 66 is configured to output to the outside that the measurement flow rate correction processing of the thermal flow sensor 16 has been completed. As the output unit 66, an image display device such as a liquid crystal display or an organic EL display, a printer, or the like can be employed.

  The input unit 67 is a functional block for inputting user operation information and the like. For example, a computer capable of inputting information such as operation buttons, a keyboard, and a mouse can be employed. Note that the function of the input unit 67 may be included in the output unit 66. For example, when the output unit 66 is an image display device having a touch panel, the user can supply operation information to the output unit 66 using the touch panel.

  FIG. 9 is a flowchart for correcting the measured flow rate of the thermal flow sensor 16 of the correction value determination device 2 according to the second embodiment of the present invention.

  First, in step S11, the vortex flow meter 120 measures the average flow rate Q2.

  Next, in step S12, the flow rate determination unit 63 of the control unit 60 of the vortex flow meter 120 determines whether or not at least the average flow rate Q2 measured by the vortex flow meter 120 is within a correction (measurement) flow rate range. To do.

  When the flow rate determination unit 63 determines that the average flow rate Q2 is not within the correction (measurement) possible flow rate range, the process of correcting the measurement flow rate of the thermal flow meter (thermal flow sensor 16) ends.

  When the flow rate determination unit 63 determines that the average flow rate Q2 is within the correction (measurement) possible flow rate range, the process proceeds to step S3. In step S13, the thermal flow meter (thermal flow sensor 16) receives a flow measurement start request from the vortex flow meter 20, and measures the average flow rate Q1.

  In step 14, the thermal flow meter transmits the measured average flow rate Q 1 to the vortex flow meter 120.

  In step S15, the vortex flow meter 120 measures the average flow rate Q2.

  In step S16, the flow rate comparison unit 65 of the vortex flow meter 120 compares the average flow rate Q1 measured by the thermal flow meter with the average flow rate Q2 measured by the vortex flow meter 120.

  In step S17, the flow rate comparing unit 65 determines whether or not the difference (error) between the average flow rate Q1 measured by the thermal flow meter and the average flow rate Q2 measured by the vortex flow meter 120 is greater than a predetermined threshold value. .

  When the flow rate comparison unit 65 determines that the difference (error) between the average flow rate Q1 and the average flow rate Q2 is not greater than a predetermined threshold value, the process proceeds to step S22, which will be described later, and the vortex flow meter 120 is replaced with a thermal flow meter. The fact that the correction of the measured flow rate has been completed (in fact, the correction is not performed) is output externally.

  When the flow rate comparison unit 65 determines that the difference (error) between the average flow rate Q1 and the average flow rate Q2 is greater than a predetermined threshold value, the process proceeds to step S8. In step S18, the vortex flow meter 120 transmits the error and the correction command for the measured flow rate of the thermal flow meter to the thermal flow meter.

  In step S19, the thermal flow meter receives the error and the correction command for the measured flow rate of the thermal flow meter from the vortex flow meter 120, and corrects the average flow rate Q1 measured by the thermal flow meter. Determine the correction value.

  In step S20, the average flow rate Q1 measured by the thermal flow meter is corrected based on the correction value.

  In step 21, the thermal flow meter 1 reports to the vortex flow meter 120 that the correction process has been completed.

  In step 22, the vortex flow meter 120 outputs to the outside that the correction process has been completed.

  According to the embodiment described above, the flow rate of the target measurement fluid can be easily corrected, and the flow rate of the measurement target fluid can be accurately measured. In particular, in the second embodiment, the flow meter member including the vortex flow meter for measuring the flow rate of the fluid to be measured is configured to be detachable from the pipe, so that the flow meter member is only necessary when the vortex flow meter is required. Therefore, it is not necessary to use a composite flow meter in which a thermal flow meter and a vortex flow meter are integrated in advance. be able to.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be combined in various ways and can be modified and applied. For example, the functions of the thermal flow meters of the correction value determining devices 1 and 2 may be provided by the components of the vortex flow meters 20 and 120, Each component of the thermal flow meter may have a function that each component of the vortex flow meters 20 and 120 has. For example, the output unit 46 may have the function of the output unit 66 of the vortex flow meter 120. Further, the storage unit 61 of the thermal flow meter may be configured to store a predetermined threshold value stored in the storage unit 61 of the vortex flow meter 120 and the above information. Furthermore, the storage unit 61 may be configured to store information indicating the relational expression or the relation table stored in the storage unit 51, the correction value, and the like.

  Furthermore, in each embodiment of the present invention, the thermal flow sensor 16, the vortex flow sensor 22, the pressure sensor 24, and the temperature sensor 26 are provided with only one each, but the number of each sensor There is no particular limitation. For example, in the case where a plurality of thermal flow sensors 16 are provided, it is possible to employ a probable measurement value as the fluid flow rate by comparing the flow measurement values of the sensors.

  Furthermore, the flow rate comparison process performed by the flow rate comparison unit 65 of the control means 60 of the vortex flow meter 120 may be configured to be executed by the control means 50 of the thermal flow meter.

  Still further, the correction value determination devices 1 and 2 determine whether the difference (error) between the average instantaneous flow rate Q1 and the average instantaneous flow rate Q2 is greater than a predetermined threshold by the control means 40, 50, and 60. You may be comprised so that the presence or absence of abnormality of the flow sensor 16 may be judged. Furthermore, the output units 46 and 66 may be configured to perform notification of determination results when the control means 40, 50, and 60 determine whether or not the thermal flow sensor 16 is abnormal.

  In the present embodiment, it has been described that the output unit 66 outputs to the outside that the measurement flow rate correction process of the thermal flow sensor 16 has been completed. However, the output unit 46 of the control means 40 and 50 of the thermal flow meter You may output outside that the correction process of the measurement flow volume of the thermal flow sensor 16 was completed.

  Note that the steps in the flowchart shown in FIG. 4 are not necessarily executed in the order of S1 to S8. For example, either step S3 or step S4 may be executed first. Further, the steps in the flowchart shown in FIG. 9 are not necessarily executed in the order of S11 to S22. For example, either step S13 or step S15 may be executed first.

  In the present invention, the “part” does not simply mean a physical means, but includes a case where the function of the “part” is realized by software. Also, even if the functions of one “unit” or device are realized by two or more physical means or devices, the functions of two or more “units” or devices are realized by one physical means or device. May be.

  Each unit in the present embodiment can be realized by using a storage area such as a memory or a hard disk, or by executing a program storing the storage area by a processor.

The present invention may include the following aspects.
(Appendix 1)
On the computer,
A first flow rate of the measurement target fluid measured by a thermal flow sensor installed in a pipe through which the measurement target fluid flows, and a second flow rate of the fluid measured by a vortex flow meter installed in the pipe With the ability to perform a comparison of
A function of determining a correction value for correcting the first flow rate based on the result of the comparison;
A program to realize
(Appendix 2)
A first flow rate of the measurement target fluid is measured by a thermal flow sensor installed in a pipe through which the measurement target fluid flows;
A flow meter member that includes a vortex flow meter for measuring a second flow rate of the fluid to be measured, and is configured to be detachable from the pipe, wherein the vortex flow meter of the flow meter member attached to the pipe To measure the second flow rate,
Performing a comparison between the measured first flow rate and the measured second flow rate;
Determining a correction value for correcting the first flow rate based on the result of the comparison;
Correction value determination method.
(Appendix 3)
Piping for circulating the fluid to be measured;
A thermal flow sensor installed in the pipe and measuring a first flow rate of the fluid to be measured;
A flow meter member that includes a vortex flow meter for measuring a second flow rate of the fluid to be measured, and is configured to be detachable from the pipe;
A flow rate comparison unit for performing a comparison between the measured first flow rate and the second flow rate measured by the vortex flow meter of the attached flow meter member;
A correction value determining unit that determines a correction value for correcting the first flow rate based on the result of the comparison,
Correction value determination device.
(Supplementary Note 4) A thermal flow sensor that is installed in a pipe through which the fluid to be measured flows and measures the first flow rate of the fluid to be measured, and a vortex that is installed in the pipe and measures the second flow rate of the fluid to be measured. Abnormality determination that determines the presence or absence of abnormality of the thermal flow sensor based on the result of the comparison, and a flow rate comparison unit that performs comparison between the measured first flow rate and the second flow rate An abnormality determination device.
(Appendix 5)
The flow rate comparison unit determines whether or not a difference between the first flow rate and the second flow rate exceeds a predetermined threshold value, and the abnormality determination unit determines whether the difference exceeds the predetermined threshold value by the flow rate comparison unit. The abnormality determination device according to appendix 4, wherein it is determined that the thermal flow sensor is abnormal when it is determined that the temperature exceeds the upper limit.
(Appendix 6)
An abnormality determination method for determining whether there is an abnormality in a thermal flow sensor,
In the pipe through which the measurement target fluid is circulated, the first flow rate of the measurement target fluid is measured,
In the pipe, measure the second flow rate of the fluid to be measured,
Performing a comparison between the measured first flow rate and the second flow rate;
Based on the result of the comparison, the presence or absence of abnormality of the thermal flow sensor is determined.
Abnormal judgment method.
(Appendix 7)
A program for realizing a function for judging whether there is an abnormality in a thermal flow sensor,
A function of measuring a first flow rate of the measurement target fluid in a pipe through which the measurement target fluid flows;
A function of measuring the second flow rate of the fluid to be measured in the pipe;
A function of performing a comparison between the measured first flow rate and the second flow rate;
A function of determining the presence or absence of an abnormality of the thermal flow sensor based on the result of the comparison;
A program to realize

1, 2 Correction value determination device 12 Piping 14 Rectification mechanism 16 Thermal flow sensor 20, 120 Vortex flow meter 21 Vortex generator 22 Vortex flow sensor 24 Pressure sensor 26 Temperature sensor 30 Inlet 32 Outlet 40, 50, 60 Control means 41, 51, 61 Storage unit 42, 52, 63 Flow rate determination unit 43, 65 Flow rate comparison unit 44, 53 Correction value determination unit 45, 54 Flow rate correction unit 46, 66 Output unit 47, 67 Input unit 100 Flow meter member 110a, b Detachable mechanism

Claims (9)

A thermal flow sensor that is installed in a pipe through which the fluid to be measured flows, and that measures the first flow rate of the fluid to be measured;
A vortex flow meter installed in the pipe for measuring a second flow rate of the fluid to be measured;
A flow rate comparison unit for performing a comparison between the measured first flow rate and the second flow rate;
A correction value determining unit that determines a correction value for correcting the first flow rate based on the result of the comparison,
Flowmeter. A flow rate determination unit for determining whether the flow rate of the fluid to be measured is within a range in which both the thermal flow sensor and the vortex flow meter can be measured;
The correction value determination apparatus according to claim 1. Whether the difference between the first flow rate and the second flow rate exceeds a predetermined threshold when the thermal flow sensor and the vortex flow meter are both within a measurable range. Judging
The correction value determining unit determines a correction value for correcting the first flow rate when the difference exceeds the predetermined threshold;
The correction value determination apparatus according to claim 2. A flow rate correction unit for correcting the first flow rate;
The flow rate correction unit corrects the first flow rate based on the correction value.
The correction value determination apparatus of any one of Claims 1-3. The flow rate correction unit is
Outputting the first flow rate corrected with the determined correction value as a third flow rate measured by the thermal flow sensor;
The correction value determination apparatus according to claim 4. A storage unit that stores a relational expression or a relation table indicating a relation between the correction value and a difference between the first flow rate and the second flow rate;
The correction value determination apparatus of any one of Claims 1-5. The vortex flow meter is installed downstream of the thermal flow sensor in the pipe.
The correction value determination apparatus of any one of Claims 1-6. The first flow rate and the second flow rate are average flow rates in a predetermined flow rate measurement period.
The correction value determination apparatus of any one of Claims 1-7. A first flow rate of the measurement target fluid is measured by a thermal flow sensor installed in a pipe through which the measurement target fluid flows;
A second flow rate of the fluid is measured by a vortex flow meter installed in the pipe;
Performing a comparison between the measured first flow rate and the second flow rate;
Determining a correction value for correcting the first flow rate based on the result of the comparison;
Correction value determination method.

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