Liquid level monitoring device and judgment method

Abstract

The invention discloses a liquid level monitoring device and a judging method.The liquid level monitoring device comprises a liquid storage tank, a pipeline assembly, a measuring area and an industrial personal computer, the liquid storage tank is used for containing liquid, the measuring area is arranged on one side of the liquid storage tank, a datum point and a plurality of detection points are arranged in the measuring area, and the detection points are arranged on the side, away from the liquid storage tank, of the datum point; the datum point and the plurality of detection points are provided with static force level gauges, the liquid storage tank is communicated with the static force level gauges through pipeline assemblies, the industrial personal computer is arranged on one side, away from the datum point, of each detection point, the industrial personal computer is in communication connection with the static force level gauges, and the industrial personal computer is used for collecting liquid path pressure values of the datum point and the detection points and dynamically monitoring changes of the liquid path pressure values. The liquid level change of the liquid storage tank is controlled in real time, and a linear equation corresponding to the liquid level pressure value and time is fitted through the industrial personal computer according to the change of the liquid path pressure value, so that the dynamic change and trend of the liquid level are predicted in advance.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid level detection, and particularly to a liquid level monitoring device and a determination method. Background Art

[0002] A static level gauge is a sensor that measures the change in liquid level pressure based on the principle of a silicon piezoresistive pressure sensor and is applied to liquid level and settlement monitoring scenarios. In actual application, a liquid and a gas path are filled in the measurement system to form a closed measurement system, and settlement data is obtained through the change in the liquid level difference between the reference point and the detection point.

[0003] During the application of the static level gauge, it is crucial whether the liquid height level in the liquid storage tank and the pipeline is at a normal level. Since pipeline breakage, aging, and liquid evaporation will cause problems in the measurement system, and the rapid loss of liquid will cause the measurement system to fail. Traditional detection methods are relatively lagging and cannot predict the dynamic changes and trends of the liquid level in advance. Summary of the Invention

[0004] In view of the above situation, it is necessary to provide a liquid level monitoring device and a determination method for the problem that the dynamic changes and trends of the liquid level cannot be predicted in advance in the prior art.

[0005] A liquid level monitoring device includes a liquid storage tank, a pipeline assembly, a measurement area, and an industrial control computer. The liquid storage tank is used to hold liquid. A measurement area is provided on one side of the liquid storage tank. A reference point and a plurality of detection points are arranged in the measurement area. The reference point and the plurality of detection points are arranged side by side. The plurality of detection points are arranged on the side of the reference point away from the liquid storage tank. Static level gauges are arranged at the reference point and the plurality of detection points. The liquid storage tank is connected to the static level gauges through the pipeline assembly. The static level gauges are used to measure the liquid path pressures at the reference point and the detection points. The industrial control computer is arranged on the side of the detection point away from the reference point, and the industrial control computer is communicatively connected to the static level gauges.

[0006] Advantages of the present invention:

[0007] Connect the liquid storage tank filled with liquid to the reference point and the detection points, then set static level gauges at the reference point and the detection points, collect the liquid path pressure values of the reference point and the detection points by using the industrial control computer, dynamically monitor the change of the liquid path pressure values, realize the real-time control of the liquid level change of the liquid storage tank, fit a linear equation corresponding to the liquid level pressure value and time through the industrial control computer according to the change of the liquid path pressure values, obtain the slope and intercept of the linear equation, obtain the predicted liquid level loss days through the slope and the intercept, and obtain the predicted liquid loss amount based on the predicted liquid level loss days to complete the liquid level monitoring, so as to predict the dynamic changes and trends of the liquid level in advance, so as to make early intervention on the liquid storage tank and ensure the effective operation of the liquid storage tank.

[0008] Further, the pipeline assembly includes a liquid pipeline and a backpressure pipeline. A cavity is formed between the top of the liquid in the liquid storage tank and the top of the liquid storage tank. The liquid pipeline is connected to the bottom of the liquid storage tank, and the backpressure pipeline is connected to the upper part of the liquid storage tank and communicates with the cavity.

[0009] Further, the static level gauge includes a liquid level chamber and a backpressure chamber. There is a gap between the liquid level chamber and the backpressure chamber. The liquid level chamber communicates with the liquid pipeline, and the backpressure chamber communicates with the backpressure pipeline.

[0010] Further, the industrial control computer is connected to several of the static level gauges through RS485 data lines.

[0011] Further, the liquid is one of water, distilled water or antifreeze.

[0012] The present invention also provides a liquid level determination method, which is applied to the static monitoring device as described above. The method includes the following steps:

[0013] A measurement area is set on one side of the liquid storage tank. A reference point and several detection points are set in the measurement area. The reference point and the several detection points are arranged side by side, and the several detection points are located on the side of the reference point away from the liquid storage tank. Static level gauges are set on the reference point and the detection points.

[0014] The static level gauges are connected to the liquid storage tank through the pipeline assembly, and the industrial control computer is communicatively connected to the static level gauges.

[0015] The static level gauges are started to measure the liquid path pressure of the reference point and the liquid path pressures of the several detection points, so as to obtain the reference liquid path pressure value P 基液 and several detected liquid path pressure values P i for liquid detection;

[0016] Through the reference liquid path pressure value P 基液 and several of the detected liquid path pressure values P i检液 , several fitting pressure differences P 拟 are obtained;

[0017] Using several of the fitting pressure differences P 拟 as the Y-axis and the measurement duration T as the X-axis, a coordinate system is constructed, and coordinate points are marked in the coordinate system;

[0018] The several coordinate points are fitted into a linear equation to obtain the slope and intercept of the linear equation;

[0019] Based on the slope and the intercept, obtain the predicted number of days of liquid level loss, and based on the predicted number of days of liquid level loss, obtain the predicted liquid loss amount to complete liquid level monitoring.

[0020] Further, the measurement duration T is greater than or equal to 2 days.

[0021] Further, the linear equation is: y = kT + b, where k represents the slope, T represents the measurement duration, b represents the intercept, and y represents the fitted pressure difference. Description of the Drawings

[0022] Figure 1 is a schematic structural diagram of the liquid level monitoring device of the present invention;

[0023] Figure 2 are the steps of the liquid level determination method of the present invention.

[0024] 1. Liquid storage tank; 11. Cavity; 2. Pipeline assembly; 21. Liquid pipeline; 22. Back pressure pipeline; 3. Measurement area; 31. Reference point; 32. Detection point; 4. Industrial control computer; 5. Static level gauge; 51. Liquid level cavity; 52. Back pressure cavity; 6. Liquid; 7. RS485 data line. Detailed Embodiments

[0025] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0026] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items. Moreover, the features between the embodiments of the present invention, the features in the embodiments, and the features of the embodiments can be freely combined on the premise of no obvious conflict or contradiction.

[0028] A liquid level monitoring device, such asFigure 1 As shown in the figure, it includes a liquid storage tank 1, a pipeline assembly 2, a measurement area 3, and an industrial control computer 4.

[0029] Specifically, the liquid storage tank 1 is used to hold the liquid 6, and the liquid is one of water, distilled water, or antifreeze. A measurement area 3 is provided on one side of the liquid storage tank 1. A reference point 31 and a plurality of detection points 32 are arranged in the measurement area 3. The reference point 31 and the plurality of detection points 32 are arranged side by side. The plurality of detection points 32 are arranged on the side of the reference point 31 away from the liquid storage tank 1. Static level gauges 5 are arranged at both the reference point 31 and the plurality of detection points 32. The liquid storage tank 1 is connected to the static level gauges 5 through the pipeline assembly 2. The pipeline assembly 2 includes a liquid pipeline 21 and a back-pressure pipeline 22. A cavity 11 is formed between the top of the liquid 6 in the liquid storage tank 1 and the top of the liquid storage tank 1. The liquid pipeline 21 is connected to the bottom of the liquid storage tank 1, and the back-pressure pipeline 22 is connected to the upper part of the liquid storage tank 1 and communicates with the cavity 11. The static level gauge 5 includes a liquid level cavity 51 and a back-pressure cavity 52. There is a gap between the liquid level cavity 51 and the back-pressure cavity 52. The liquid level cavity 51 communicates with the liquid pipeline 21, and the back-pressure cavity 52 communicates with the back-pressure pipeline 22. The static level gauge 5 is used to measure the liquid pressure in the pipeline. The industrial control computer 4 is arranged on the side of the detection point 32 away from the reference point 31. The industrial control computer 4 is connected to the static level gauge 5 through an RS485 data line 7. The liquid storage tank 1 containing the liquid 6 is connected to the reference point 31 and the plurality of detection points 32, and then static level gauges 5 are arranged at the reference point 31 and the plurality of detection points 32. The industrial control computer 4 is used to collect the liquid pressure values at the reference point 31 and the plurality of detection points 32, dynamically monitor the change of the liquid pressure values, and realize the real-time control of the liquid level change of the liquid storage tank 1. According to the change of the liquid pressure values, a prediction model corresponding to the liquid level and time is fitted through the industrial control computer 4, so as to predict the dynamic change and trend of the liquid level in advance, so as to make early intervention on the liquid storage tank 1 and ensure the effective operation of the liquid storage tank 1. The back-pressure pipeline 22 is respectively connected to the liquid storage tank 1 and the back-pressure cavity 52, and no vacuum is pumped during the installation and connection process. When there is a liquid leakage, the liquid in the liquid storage tank 1 will decrease, and the air in the back-pressure cavity 52 will fill the liquid storage tank 1 to maintain the air pressure balance in the liquid storage tank 1. Since the liquid storage tank 1 itself has good airtightness, if there is no other air filling, it will cause the liquid storage tank 1 to form a relative vacuum, affecting the normal operation of the static level gauge 5.

[0030] The present invention also provides a liquid level determination method, which is applied to the static monitoring device as described above. As Figure 2 shown in the figure, the method includes the following steps:

[0031] S1: Set up a measurement area 3 on one side of the liquid storage tank 1. Set a reference point 31 and several detection points 32 in the measurement area 3. The reference point 31 and the several detection points 32 are arranged side by side, and the several detection points 32 are located on the side of the reference point 31 away from the liquid storage tank 1. Static level gauges 5 are set on both the reference point 31 and the detection points 32.

[0032] S2: Connect the static level gauges 5 to the liquid storage tank 1 through the pipeline assembly 2, and communicatively connect the industrial control computer 4 to the static level gauges 5.

[0033] S3: Start the static level gauges 5, measure the liquid path pressure of the reference point 31 and the liquid path pressures of the several detection points 32, so as to obtain the reference liquid path pressure value P 基液 and several detected liquid path pressure values P i检液 ;

[0034] S4: Through the reference liquid path pressure value P 基液 and the several detected liquid path pressure values P i检液 , obtain several fitting pressure differences P 拟 ;

[0035] S5: Use the several fitting pressure differences P 拟 as the Y-axis and the measurement duration T as the X-axis to construct a coordinate system, and mark coordinate points in the coordinate system.

[0036] S6: Fit the several coordinate points into a linear equation to obtain the slope and intercept of the linear equation.

[0037] S7: Through the slope and the intercept, obtain the predicted liquid level loss days, and based on the predicted liquid level loss days, obtain the predicted liquid loss amount to complete the liquid level monitoring.

[0038] Specifically, the measurement duration T is greater than or equal to 2 days.

[0039] Specifically, the linear equation is: y = kT + b, where k represents the slope, T represents the measurement duration, b represents the intercept, and y represents the fitting pressure difference.

[0040] Now, taking the measurement duration of 10 days as an example, collect the liquid path pressure value P 基液 of the reference point 31 and the liquid path pressure values P i检液 of multiple detection points 32 through the industrial control computer 4, subtract the two to obtain the fitting pressure difference P 拟 , then use the fitting pressure difference P 拟 as the Y-axis and the measurement duration as the X-axis to form a coordinate system, mark coordinate points in the coordinate system, fit out a linear equation, and the statistical data is shown in Table 1:

[0041] Table 1

[0042]

[0043]

[0044] As can be seen from Table 1, according to the principle that two points determine a straight line, the fitting pressure difference P on the first day 拟 cannot fit a linear equation. Starting from the second day, combining with the previous fitting pressure difference P 拟 , a linear equation is fitted. As the number of measurement days increases, the fitting pressure difference P 拟 may also show some fluctuations, and the slope and intercept of the fitted linear equation also change accordingly. According to the liquid pressure formula: p = ρgh, when ρ and g remain unchanged, P 基液 and P i检液 are both related to the liquid level height h, that is, the fitting pressure difference P 拟 is directly related to the liquid level height h. Then, the absolute value of "intercept b / slope k" is calculated by using the industrial control computer 4, and the absolute value is used as the predicted liquid level loss days. Based on the predicted liquid level loss days, the predicted liquid loss amount is obtained, so as to complete the liquid level monitoring of the storage tank 1, and predict in advance the dynamic change and trend of the liquid level of the storage tank 1. It should be noted that since the liquid path pressure of the static level gauge 5 will be affected by factors such as load and temperature, in order to minimize the interference of data by external factors, the measurement time every day is from 0:00 to 4:00, and P i检液 takes the median of all data on the same day as the data of the same day.

[0045] In the present invention, P 基液 and P i检液 are a set of data that change with time and are interrelated. When the liquid level of the storage tank 1 drops (evaporation, leakage, etc.), the liquid path pressure of the storage tank 1 will show a downward trend. By fitting the data of the liquid path pressure value, a linear equation is obtained, and then the absolute value of "intercept b / slope k" is calculated by using the industrial control computer 4, and the absolute value is used as the predicted liquid level loss days. Based on the predicted liquid level loss days, the predicted liquid loss amount is obtained, so as to complete the liquid level monitoring of the storage tank 1.

[0046] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or special parts described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or special parts described can be combined in a suitable manner in any one or more embodiments or examples.

[0047] The above-described embodiments merely represent the implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent for the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be subject to the appended claims.

Claims

1. A liquid level monitoring device, characterized in that: It includes a liquid storage tank, a pipeline assembly, a measuring area and an industrial computer. The liquid storage tank is used to contain liquid. A measuring area is provided on one side of the liquid storage tank. A reference point and a plurality of detection points are arranged in the measuring area. The reference point and the plurality of detection points are distributed side by side. The plurality of detection points are arranged on a side of the reference point away from the liquid storage tank. A static level is arranged on the reference point and the plurality of detection points. The liquid storage tank is connected to the static level through the pipeline assembly. The static level is used to measure the liquid circuit pressure at the reference point and the detection point. The industrial computer is arranged on a side of the detection point away from the reference point. The industrial computer is communicatively connected to the static level.

2. The liquid level monitoring device according to claim 1, characterized in that: The pipeline assembly includes a liquid pipeline and a back pressure pipeline. A cavity is formed between the top of the liquid in the liquid storage tank and the top of the liquid storage tank. The liquid pipeline is connected to the bottom of the liquid storage tank, and the back pressure pipeline is connected to the upper part of the liquid storage tank and communicates with the cavity.

3. The liquid level monitoring device according to claim 2, characterized in that: The static level comprises a liquid level cavity and a back pressure cavity, a space is provided between the liquid level cavity and the back pressure cavity, the liquid level cavity is communicated with the liquid pipeline, and the back pressure cavity is communicated with the back pressure pipeline.

4. The liquid level monitoring device according to claim 1, characterized in that: The industrial computer is connected to the plurality of static levels via an RS485 data line.

5. The liquid level monitoring device according to claim 1, characterized in that: The liquid is one of water, distilled water or antifreeze.

6. A liquid level determination method, characterized in that: Applied to the static monitoring device according to any one of claims 1 to 5, the method comprises the following steps: A measuring area is set on one side of the liquid storage tank, a reference point and a plurality of detection points are set in the measuring area, the reference point and the plurality of detection points are set side by side, and the plurality of detection points are located on a side of the reference point away from the liquid storage tank, and a static level is set on both the reference point and the detection point; Connecting the static level with the liquid storage tank through a pipeline assembly, and connecting the industrial computer with the static level for communication; Start the static level to measure the pressure of the fluid circuit at the reference point and the pressure of the fluid circuit at several detection points, so as to obtain the reference fluid circuit pressure value P through the industrial computer. 基液 and several test fluid pressure values ​​P i Test fluid; Through the reference liquid circuit pressure value P 基液 and several of the detection fluid path pressure values ​​P i检液 , obtain several fitting pressure difference values ​​P 拟 ; With several said fitting pressure difference values ​​P 拟 as the Y-axis, the measurement duration T as the X-axis, construct a coordinate system, and mark the coordinate points in the coordinate system; Fitting a number of the coordinate points into a linear equation, and obtaining the slope and intercept of the linear equation; The predicted number of days for liquid level loss is obtained through the slope and the intercept, and the predicted liquid loss amount is obtained based on the predicted number of days for liquid level loss to complete liquid level monitoring.

7. The liquid level determination method according to claim 6, characterized in that: The measurement duration T is greater than or equal to 2 days.

8. The liquid level determination method according to claim 6, characterized in that: The linear equation is: y=kT+b, Where k is the slope, T is the measurement duration, b is the intercept, and y is the fitted pressure difference.

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