Radar-based sewer water level and flow rate measuring device

Abstract

A radar-based sewer water level and flow rate measuring device is provided. [Solution] A sewage water level and flow velocity measuring device 100 is provided, which is equipped with a water level radar sensor 110 that measures the water level of sewage flowing through a sewer pipe, a flow velocity radar sensor 120 that measures the flow velocity of the sewage, and a fixing device 130 for fixing the water level radar sensor and the flow velocity radar sensor to the sewer pipe.

Description

Technical Field

[0001] The present invention relates to a sewage water level and flow velocity measuring device using a radar.

Background Art

[0002] As a technique related to the measurement of sewage flow rate, Patent Document 1 is known. Patent Document 1 is a method for creating flow rate data at a plurality of locations in order to investigate unknown water at a plurality of locations in a sewage pipeline facility. The method discloses obtaining flow rate data at a plurality of locations by using measurement data temporarily measured by a flow meter or a flow velocity meter at each of the plurality of locations, Manning's formula, and water level data continuously measured by a water level meter installed at each of the plurality of locations.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a sewage water level and flow velocity measuring device that is attached to a sewage pipe and measures the water level and flow velocity of sewage flowing through the sewage pipe.

Means for Solving the Problems

[0005] The present invention includes the following aspects. [1] A radar sensor for water level that measures the water level of sewage flowing through a sewage pipe, A radar sensor for flow velocity that measures the flow velocity of the sewage, And a fixture for fixing the radar sensor for water level and the radar sensor for flow velocity to the sewage pipe A sewage water level and flow velocity measuring device comprising the same. [2] The sewage water level and flow velocity measuring device according to [1], wherein a first lens for narrowing the irradiation range of the radar wave is mounted on the radar surface of the radar sensor for flow velocity. [3] The sewage water level and flow velocity measuring device according to [2], wherein a second lens for narrowing the irradiation range of the radar wave is mounted on the radar surface of the radar sensor for water level. [4] The sewage water level and flow velocity measuring device according to [3], wherein at least one surface of the radar surface of the radar sensor for flow velocity, the radar surface of the radar sensor for water level, the first lens, and the second lens is coated with a water-repellent coating. [5] The sewage water level and flow velocity measuring device according to [1], wherein the fixture is adapted to fit the shape of the inner top or outer top of the sewer pipe. [6] The water level radar sensor transmits to the water surface of the sewage, and measures the water level of the sewage based on the reception time of the pulse wave reflected from the water surface. The sewage water level and flow velocity measuring device according to [1], wherein the flow velocity radar sensor measures the flow velocity of the sewage based on the difference between the frequency of the radar wave transmitted to the water surface of the sewage and the frequency of the radar wave reflected from the water surface. [7] The sewage water level and flow velocity measuring device according to [1], further comprising storage means for storing data on the measured sewage water level and flow velocity, and / or communication means for transmitting the data to an external device. [8] [1] to [7], any one of the sewage water level and flow velocity measuring devices according to any one of the preceding claims, and mounting the device on the inner top or outer top of the sewer pipe. A method comprising the step of measuring the water level and flow velocity of the sewage flowing through the sewer pipe using the sewage water level and flow velocity measuring device. [9] A plurality of sewage water level and flow velocity measuring devices according to any one of [1] to [7], And a management device for managing data on the water level and flow velocity of the sewage sent from the sewage water level and flow velocity measuring device. A sewage management system having the same.

Brief Description of the Drawings

[0006]

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Embodiments for Carrying Out the Invention

[0007] [First Embodiment] Figure 1 is a schematic diagram of the sewage water level and flow velocity measuring device 100 according to the first embodiment of the present invention.

[0008] The sewage water level and flow velocity measuring device 100 includes a radar sensor 110 for water level that measures the water level of the sewage flowing in the sewer pipe, a radar sensor 120 for flow velocity that measures the flow velocity of the sewage, and a fixture 130 for fixing the radar sensor 110 for water level and the radar sensor 120 for flow velocity to the sewer pipe.

[0009] The fixture 130 has a gripping portion 134 that grips the water level radar sensor 110 and the flow velocity radar sensor 120 facing downward into the sewage, and a mounting portion 132 for attaching the water level radar sensor 110 and the flow velocity radar sensor 120 to the inner top of the sewer pipe.

[0010] If the sewer pipe is made of resin, since the radar from the water level radar sensor 110 and the flow velocity radar sensor 120 can penetrate the resin, the sewage water level and flow velocity measuring device 100 may be attached to the outer top (the outer surface of the cylinder) instead of the inner top of the sewer pipe.

[0011] Here, the inner top (or outer top) can be said to be, for example, the portion of the inner surface of the sewer pipe (or outer top) at the highest position among the straight lines (diameters) passing through the central axis of the sewer pipe when the sewer pipe is laid horizontally. Note that this portion is not limited to a narrow range of points, and a certain range is allowed as long as the water level and flow velocity can be measured.

[0012] The fixture 130 is adapted to fit the shape of the inner top (or outer top) of the sewer pipe. For example, since the sewer pipe is generally cylindrical, the mounting portion 132 of the fixture 130 may be configured in a curved shape or a relatively small shape so as to fit the top shape on the circumferential surface of the sewer pipe. Also, the fixture 130 is preferably made of metal or resin that is not easily corroded even in a high-humidity environment.

[0013] The fixture 130 (gripping portion 134) grips the water level radar sensor 110 and the flow velocity radar sensor 120 such that the radar surfaces 112 of the water level radar sensor 110 and 122 of the flow velocity radar sensor 120 face the water surface. Preferably, the fixture 130 grips the water level radar sensor 110 and the flow velocity radar sensor 120 such that the radar surface 112 is substantially parallel to the water surface (for example, the angle formed by the radar surface 112 and the water surface is 0° ± 15°), and the radar surface 122 is inclined at a predetermined angle with respect to the water surface (for example, the angle formed by the radar surface 122 and the water surface is 40° ± 20°).

[0014] The water level radar sensor 110 transmits radar waves (preferably pulse waves) from the radar surface 112 to the water surface of the sewage, and receives the pulse waves reflected from the water surface at the radar surface 112. Then, the water level radar sensor 110 measures the water level of the sewage based on the time from the transmission to the reception of the pulse waves. The pulse waves are millimeter waves or microwaves with a relatively short wavelength (for example, in the frequency range of 10 GHz to 300 GHz). For example, the frequency of the radar waves (pulse waves) of the water level radar sensor 110 is 10 to 100 GHz, 20 to 80 GHz, or 24 to 60 GHz.

[0015] The flow velocity radar sensor 120 transmits radar waves from the radar surface 122 to the water surface of the sewage, and receives the radar waves reflected from the water surface at the radar surface 122. Then, the flow velocity radar sensor 120 utilizes the Doppler effect and measures the flow velocity of the sewage based on the difference between the frequency of the radar waves transmitted to the water surface of the sewage and the frequency of the radar waves reflected from the water surface. When the frequency of the received radar waves is higher than the frequency of the transmitted radar waves, the flow velocity of the sewage is fast, and when the frequency of the received radar waves is lower than the frequency of the transmitted radar waves, the flow velocity of the sewage is slow. For example, the frequency of the radar waves of the flow velocity radar sensor 120 is 10 to 100 GHz, 20 to 80 GHz, or 24 to 60 GHz.

[0016] Here, with reference to FIG. 2, the measurement principles of the water level and flow velocity of the sewage will be described. FIG. 2 is a schematic cross-sectional view taken along the central axis of the sewer pipe 1 when the sewage water level and flow velocity measuring device 100 is attached to the inner top 1a of the sewer pipe 1. Note that even when the sewage water level and flow velocity measuring device 100 is attached to the outer top of the sewer pipe 1, the measurement principles of the water level and flow velocity of the sewage are the same, and the description is omitted.

[0017] First, regarding the sewage level, the distance h0 from the radar surface 112 of the water level radar sensor 110 of the sewage water level and flow rate measuring device 100 attached to the inner top 1a of the sewer pipe 1 to the bottom 1b of the sewer pipe in a state without water is known. Also, the time T0 from when the pulse wave transmitted from the radar surface 112 is reflected by the bottom 1b of the sewer pipe in a state without water and received by the radar surface 112 is also known. When sewage flows in the sewer pipe 1, the radar surface 112 of the water level radar sensor 110 will receive the pulse wave reflected by the water surface 2. At this time, if the time from the transmission to the reception of the pulse wave by the water level radar sensor 110 is T1 (<T0), the sewage level h2 can be obtained from h2 = a×h0(1 - T1 / T0). Here, a is a predetermined coefficient according to the installation environment and the like.

[0018] Next, regarding the flow rate of the sewage, let the angle formed between the radar surface 122 of the flow rate radar sensor 120 of the sewage water level and flow rate measuring device 100 attached to the inner top 1a of the sewer pipe 1 and the sewage water surface 2 be θ, the frequency of the radar wave transmitted from the radar surface 122 be f0, the frequency of the radar wave reflected by the water surface 2 and received by the radar surface 122 be f1, and the speed of the radar wave be c. Then, the flow rate v of the sewage (the speed in the direction along the flow path of the sewer pipe 1) can be obtained from v = b×c(f1 - f0) / f0cosθ. Here, b is a predetermined coefficient according to the installation environment and the like, and the direction in which the water flow faces the radar surface 122 (the right side toward the paper surface of FIG. 2) is defined as the positive direction of the sewage flow rate.

[0019] FIG. 3A is a functional block diagram of the water level radar sensor 110. The water level radar sensor 110 includes a control unit 114 having a processor and the like that performs functions such as transmitting, receiving, and calculating the water level of the radar wave from the radar surface 112, a storage unit 115 having a memory and the like that stores programs and various data for controlling the control unit 114, and a communication unit 116 that transmits data related to the measured sewage water level to an external device (not shown). The communication unit 116 may be a communication terminal provided with an interface terminal capable of wired communication (such as USB (registered trademark)) and / or an antenna capable of wireless communication (such as Bluetooth (registered trademark), Wi-Fi (registered trademark)).

[0020] Figure 3B is a functional block diagram of the flow velocity radar sensor 120. The flow velocity radar sensor 120 includes a control unit 124 equipped with a processor or the like that transmits, receives, and calculates the flow velocity of radar waves from the radar surface 122, and a storage unit 125 equipped with a memory or the like that stores programs and various data for controlling the control unit 124, and a communication unit 126 that transmits data related to the measured sewage channel to an external device (not shown). The communication unit 126 may be a communication terminal equipped with an interface terminal capable of wired communication (such as USB (registered trademark)) and / or an antenna capable of wireless communication (such as Bluetooth (registered trademark), Wi-Fi (registered trademark)).

[0021] The sewage water level and flow velocity measuring device 100 of the present embodiment can be installed inside or outside a relatively small and narrow sewage pipe, and can measure both the sewage water level and the flow velocity. The inside of the sewage pipe usually has not only water but also various foreign objects flowing through it. Since the sewage water level and flow velocity measuring device 100 can measure the sewage water level and flow velocity non-contact using radar waves, it does not obstruct the flow of sewage (is unlikely to cause sewage blockage).

[0022] [Second Embodiment] Figure 4 is a schematic cross-sectional view of the sewage water level and flow velocity measuring device 200 according to the second embodiment of the present invention.

[0023] As shown in Figure 4, the sewage water level and flow velocity measuring device 200 includes a water level radar sensor 110, a flow velocity radar sensor 120, and a fixture 130 for fixing the water level radar sensor 110 and the flow velocity radar sensor 120 to the sewage pipe. The water level radar sensor 110 and the flow velocity radar sensor 120 are the same as those in the first embodiment, and the description thereof is omitted.

[0024] A first lens 220 for narrowing the irradiation range of the radar wave emitted from the radar surface 122 is mounted on the radar surface 122 of the flow velocity radar sensor 120. Also, a second lens 210 for narrowing the irradiation range of the radar wave emitted from the radar surface 112 may be mounted on the radar surface 112 of the water level radar sensor 110.

[0025] The fixture 130 may be the same as that of the first embodiment, or may be in the form of a housing that integrally houses the water level radar sensor 110 and the flow velocity radar sensor 120 as shown in FIG. 4. The fixture 130 (housing) may be made of a material such as resin that transmits radar waves, or the first lens 220 and the second lens 210 may be mounted in a state of protruding from the housing so that the radar waves are not blocked by the housing.

[0026] At least one surface of the radar surface 122 of the flow velocity radar sensor 120, the radar surface 112 of the water level radar sensor 110, the first lens 220, and the second lens 210 may be coated with a water-repellent material such as fluororesin. Preferably, the surfaces of the radar surface 122, the radar surface 112, the first lens 220, and the second lens 210 are coated with a water-repellent coating. In addition, the fixture 130 may also be coated with a water-repellent coating.

[0027] Generally, the inside of the sewer pipe is a high-humidity environment, and water droplets from the sewage are likely to adhere to the radar surface and the like. Therefore, by applying a water-repellent coating to at least one surface of the radar surface 122, the radar surface 112, the first lens 220, and the second lens 210, the water droplets adhering to the surface are likely to fall downward, and the influence of the adhering water droplets on the radar waves, and thus the influence on the water level and flow velocity measurement can be reduced.

[0028] As shown in FIGS. 5 and 6, by mounting the first lens 220 on the radar surface 122 of the flow velocity radar sensor 120, the irradiation range of the radar waves emitted from the radar surface 122 can be narrowed to the irradiation range 4a near the center (in the transverse direction) of the sewer pipe 1 compared to the irradiation range 4b before mounting the first lens 220. Similarly, by mounting the second lens 210 on the radar surface 112 of the water level radar sensor 110, the irradiation range of the radar waves emitted from the radar surface 112 can be narrowed to the irradiation range 6a near the center (in the transverse direction) of the sewer pipe 1 in the transverse direction compared to the irradiation range 6b before mounting the second lens 210.

[0029] In this embodiment, the reason for attaching the first lens 220 to the radar surface 120, or attaching the first lens 220 and the second lens 210 to the radar surfaces 120 and 110 to narrow the irradiation range of the radar wave near the center (in the transverse direction) of the sewer pipe is as follows. That is, the inventor of the present invention discovered that the flow velocity of the water flow in the sewer pipe, which is relatively narrow compared to rivers and the like, is different between the vicinity of the center (in the transverse direction) of the sewer pipe and the other parts. An experimental example regarding this point is shown below.

[0030] [Experimental Example of the Flow Velocity of the Water Flow in the Sewer Pipe] As shown in Fig. 7, experimental equipment was prepared in which both ends of a water channel pipe with a diameter of 250 mm simulating a sewer pipe were connected by a water tank, and the water in another water tank was circulated by a submersible pump. A part of the water channel pipe was hollowed out and used as a location for verifying the flow velocity of the water flow. As shown in Fig. 8, the surface flow velocity on the water surface near the center (in the transverse direction) of the water channel pipe and the flow velocities at the positions (three locations) of 60% of the deepest water level from the water surface were measured using an electromagnetic flowmeter VE20 (manufactured by Soki Co., Ltd.). While changing the water level and flow velocity of the water flow through the water channel pipe variously, the flow velocity of the water flow at each measurement point was measured. The measurement results are shown in Table 1 (each value is the average value measured three times at the same point).

[0031]

Table 1

[0032] As can be seen from the results shown in Table 1, the flow velocities at the left point, middle point, and right point at 60% of the water depth are basically lower than the surface flow velocity on the water surface near the center of the water channel pipe simulating the sewer pipe, and particularly the flow velocities at the left point and right point at 60% of the water depth are even lower. That is, it was found that since the water flow in the sewer pipe has the fastest flow velocity near the center of the water surface, measuring its flow velocity is preferable for grasping the water flow in the sewer pipe. In other words, if the flow velocity of the relatively slow parts such as the left and right points at 60% of the water depth is measured to grasp the flow velocity of the sewage in the sewer pipe, the actual fast surface water flow cannot be grasped, and from the perspective of disaster prevention and other preparations, it can be said that grasping the fast surface water flow is more important.

[0033] Also, regarding the water level as well, since the deepest part of the sewage in the cylindrical sewer pipe is near the center (in the transverse direction) of the sewer pipe, it is preferable to measure the water level there. Similar to the case of the flow velocity, from the perspective of disaster prevention and other preparations, it can be said that grasping a deeper water level (more water volume) is more important.

[0034] In the sewage water level and flow velocity measuring device 200 according to the present embodiment, the first lens 220 mounted on the radar surface 122 of the flow velocity radar sensor 120 can measure the flow velocity (surface flow velocity) of the water surface of the sewage near the center of the sewer pipe, and can more accurately grasp the flow of the sewage in the sewer pipe. Also, the second lens 210 mounted on the radar surface 112 of the water level radar sensor 110 can measure the water level (the deepest) of the sewage near the center of the sewer pipe, and can more accurately grasp the water level of the sewage in the sewer pipe.

[0035] [Third Embodiment] The third embodiment of the present invention relates to a sewage management system using the sewage water level and flow velocity measuring devices 100 and 200 (FIG. 9).

[0036] A sewage management system 300 using the sewage water level and flow velocity measuring devices 100 and 200 includes the sewage water level and flow velocity measuring devices 100 and 200 attached to a plurality of sewer pipes A to E in the city, and data regarding the water level and flow velocity of the sewage sent from each of the sewage water level and flow velocity measuring devices 100 and 200 ([a1, a2], etc. in FIG. 9), and has a management device 310 (a computer or a server device) for managing (collectively) the data. There may be a plurality of management devices 310.

[0037] As shown in FIG. 9, the management device 310 may display information regarding the position, water level, and flow velocity of the sewer pipe on a display 320 or the like, or may issue an alarm (voice and / or display) for the sewer pipe (for example, sewer pipe D in FIG. 9) with a water level or flow velocity exceeding a predetermined threshold value.

[0038] By using such a sewage management system 300, the administration and the like can quickly grasp the rapid increase in the sewage level and the rapid flow velocity due to recent heavy rains and the like caused by global warming, the heat island phenomenon, etc., and enable a prompt response to the corresponding sewer pipes.

[0039] The dimensions, materials, shapes, relative positions of the components, etc. described in the above embodiments are arbitrary and are changed according to the structure of the device to which the present invention is applied or various conditions. Further, the present invention is not limited to the above embodiments specifically described.

Explanation of Reference Numerals

[0040] 100, 200 Sewage water level and flow velocity measuring devices 110 Radar sensor for water level 112 Radar surface 120 Radar sensor for flow velocity 122 Radar surface 130 Fixture 210 Second lens 220 First lens 300 Sewage management system 310 Management device

Claims

1. a water level radar sensor for measuring the water level of sewage flowing through a sewer pipe; a flow velocity radar sensor for measuring the flow velocity of the sewage; a fixture for fixing the water level radar sensor and the flow velocity radar sensor to the sewer pipe; Equipped with a first lens is attached to a radar surface of the flow velocity radar sensor to narrow an irradiation range of a radar wave to a central area of ​​the sewer pipe in a transverse direction; a second lens is attached to a radar surface of the water level radar sensor to narrow an irradiation range of a radar wave to a central area of ​​the sewer pipe in a transverse direction; a radar surface of the flow velocity radar sensor, a radar surface of the water level radar sensor, the first lens, and a surface of the second lens are water-repellent coated; The water level radar sensor transmits a pulse wave to the water surface of the sewer and measures the water level of the sewer based on the reception time of the pulse wave reflected from the water surface. The flow velocity radar sensor is a sewer water level and flow velocity measuring device that measures the flow velocity of the sewer based on the difference between the frequency of radar waves transmitted to the surface of the sewer and the frequency of radar waves reflected from the water surface.

2. 2. The sewer water level and flow velocity measuring device according to claim 1, wherein the fixture is adapted to fit the shape of an inner apex or an outer apex of a sewer pipe.

3. 2. The sewage water level and flow velocity measuring device according to claim 1, further comprising a storage means for storing data relating to the measured sewage water level and flow velocity, and a communication means for transmitting the data to an external device.

4. A plurality of sewer water level and flow velocity measuring devices according to any one of claims 1 to 3; a management device for managing data on the sewage water level and flow velocity sent from the sewage water level and flow velocity measuring device; A sewage management system having the following features:

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