JP7373772B2 - Physical quantity measuring device - Google Patents

Description

The present invention relates to a physical quantity measuring device that samples a portion of a flowing working fluid and measures physical quantities such as the concentration of components contained in the fluid.

Conventionally, as a measuring device for measuring the components of a fluid, an ultrasonic flowmeter in which a component measuring section for sampling the fluid flowing through the flow measuring section is attached to the flow measuring section is known (see, for example, Patent Document 1). .

FIG. 4 shows a cross-sectional view of a portion of the measurement flow path of the ultrasonic flowmeter described in Patent Document 1.

In this flowmeter, a main channel 101 of a measurement channel 100 is divided into multiple layers by a partition plate 102 to form a multilayer channel 103. A sub-flow path 104 for measuring the components of the fluid is attached to the multilayer flow path 103. In order to allow the fluid flowing through the main channel 101 to flow into this sub-channel 104, a protrusion 105 is disposed toward the main channel 101 on the inlet side of the multi-layer channel 103 to partially narrow the channel cross section. A sub-flow path 104 is formed in which fluid is induced to flow out from an outflow port 106 on the upstream side of the flow path 103a, and fluid is caused to flow in through an inflow port (not shown).

Then, in this sub-flow path 104, gas components are measured using infrared rays.

International Publication No. 2018/185034

However, in the conventional configuration, when the fluid in the main channel is drawn to the sub-channel 104 for measuring the components of the fluid, if the fluid flowing in the main channel 101 contains droplets such as fine water droplets, There is a problem that these droplets enter the sub-channel 104 and adversely affect component measurement. Further, in order to exhibit the ejector effect, a pressure loss that affects the flow in the main channel occurs, and if this pressure loss is reduced, there is a problem that sufficient suction force to flow into the sub flow channel 104 cannot be obtained.

The present invention solves the above-mentioned conventional problems by significantly suppressing the intrusion of liquid droplets such as water droplets into the sub-channel where characteristics such as the concentration of components contained in the fluid are measured, and It is an object of the present invention to provide a measuring device that accurately measures the concentration of components contained in a fluid in a sub-channel while reducing flow turbulence.

In order to solve the conventional problems, the physical quantity measuring device of the present invention includes a main channel through which a fluid to be measured flows, an inlet opening and an outlet opening provided in the channel wall of the main channel, and the inlet opening. and the outlet opening, an inflow direction regulating section provided at the inlet opening, and a component concentration measuring section disposed in the sub channel, the inflow direction regulating section comprising: A guide piece having a predetermined inclination angle with respect to the flow direction of the main flow path is arranged, and the predetermined inclination angle is larger than 90° in relation to the flow direction of the main flow path. , when the fluid to be measured contains liquid droplets such as minute water droplets, by configuring the relationship between the interval h between the guide pieces and the height H of the main flow path to be H>h. However, by greatly suppressing the intrusion of droplets such as water droplets and supplying a flow that does not contain droplets to the subchannel, it is possible to measure the concentration of components contained in the fluid without being affected by droplets. Measurement accuracy can be improved. Furthermore, by dividing the flow using the louver-shaped guide pieces, turbulence in the main flow can be reduced, making it possible to perform measurements in a state with little turbulence in the sub-channel. Further, since the configuration is such that the cross-sectional area of the main flow is not restricted when guiding the flow to the sub-channel, no particular pressure loss occurs.

The physical quantity measuring device of the present invention is provided with an inflow direction regulating member in which a guide piece having a predetermined inclination angle with respect to the flow direction of the main flow path is arranged at the inlet opening. By configuring the angle to be larger than 90° in relation to the flow direction, the intrusion of liquid droplets such as water droplets is greatly suppressed, and a flow containing no liquid droplets is supplied to the sub-channel, thereby preventing droplets from entering. It is possible to improve measurement accuracy such as concentration measurement of components contained in a fluid without being affected by such factors. Furthermore, by dividing the flow using the louver-shaped guide pieces, it is possible to reduce the turbulence of the flow in the main flow, and it is possible to perform measurements in a state with little turbulence in the sub-channel. Further, since the configuration is such that the cross-sectional area of the main flow is not restricted when guiding the flow to the sub-channel, no particular pressure loss occurs.

A cross-sectional diagram of the configuration of a physical quantity measuring device in Embodiment 1 of the present invention AA sectional view of FIG. 1 in Embodiment 1 of the present invention A diagram showing another shape of the AA cross section in FIG. 1 in Embodiment 1 of the present invention Cross-sectional diagram showing the configuration of a conventional component measurement unit

A first invention provides a main channel through which a fluid to be measured flows, an inlet opening and an outlet opening provided in a channel wall of the main channel, and a sub-channel connecting the inlet opening and the outlet opening. an inflow direction regulating section provided at the inlet opening; and a component concentration measuring section disposed in the sub-channel, wherein the inflow direction regulating section has a predetermined inclination with respect to the flow direction of the main channel. It is configured by arranging guide pieces with corners, and the predetermined inclination angle is a value larger than 90° in relation to the flow direction of the main flow path, and the distance h between the guide pieces and the main flow path are The physical quantity measuring device is configured such that the relationship with the height H of It is possible to improve measurement accuracy such as concentration measurement of components contained in a fluid without being affected by droplets or the like. Furthermore, by dividing the flow using the louver-shaped guide pieces, it is possible to reduce the turbulence of the flow in the main flow, and it is possible to perform measurements in a state with little turbulence in the sub-channel. Further, since the configuration is such that the cross-sectional area of the main flow is not restricted when guiding the flow to the sub-channel, no particular pressure loss occurs.

In a second invention, particularly in the first invention, the component concentration measuring section includes a pair of ultrasonic transducers disposed in the sub-channel, a temperature sensor that detects the temperature of the fluid to be measured, and a temperature sensor that detects the temperature of the fluid to be measured. A signal processing section receives signals from the pair of ultrasonic transducers and the temperature sensor and calculates the component concentration of the fluid to be measured.

In a third invention, particularly in the first invention, the component concentration measuring section calculates the component concentration of the fluid to be measured based on a heat flow sensor disposed in the sub-flow path and a signal from the heat flow sensor. It consists of a signal processing section.

Embodiments of the present invention will be described below with reference to the drawings.
However, more detailed explanation than necessary may be omitted. For example, detailed explanations of well-known matters or redundant explanations of substantially the same configurations may be omitted.

The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter recited in the claims.

(Embodiment 1)
Embodiment 1 will be described using FIGS. 1 and 2.

FIG. 1 is a sectional view of the configuration of a physical quantity measuring device according to Embodiment 1 of the present invention, and FIG. 2 is a sectional view taken along line AA in FIG. 1 according to Embodiment 1 of the present invention.

1 and 2, the main channel 1 through which the fluid to be measured flows is a channel with a rectangular cross section whose long side is a width W and whose short side is a height H. Equipped with an outlet 3.

The channel wall 4 of the main channel 1 is provided with an inlet opening 5 on the upstream side, and further provided with an outlet opening 6 on the downstream side of the inlet opening 5. A sub-channel 7 connecting the inlet opening 5 and the outlet opening 6 is arranged in parallel to the main channel 1. A pair of ultrasonic transducers 8 and 9 arranged to face each other in the flow direction and a temperature sensor 10 for detecting the temperature of the fluid are arranged in the sub-flow path 7.

The pair of ultrasonic transducers 8 and 9 and the temperature sensor 10 are electrically connected to a signal processing unit 11, and the signal processing unit 11 processes the signals from the pair of ultrasonic transducers 8 and 9 and the temperature sensor 10. The component concentration of the fluid is calculated based on the signal from the sensor 10.

In the present embodiment, the component concentration measuring section includes a pair of ultrasonic transducers 8 and 9, a temperature sensor 10, and a signal processing section 11.

At the inlet opening 5 of the sub-channel 7, an inflow direction regulating section 13 is provided with a plurality of plate-shaped or louver-shaped guide pieces 12 having a predetermined inclination angle θ with respect to the flow direction of the main channel 1. The inclination angle θ of the guide piece 12 is configured to be larger than 90° as shown in FIG. 1 in relation to the flow direction of the main flow path 1.

Further, the distance h between the guide pieces 12 is configured such that the relationship with the height H of the main flow path 1 is H>h. The distance h between the guide pieces 12 and the height H of the main flow path here are values corresponding to the representative length of the Reynolds number.

The inflow direction regulating portion 13 is arranged so as not to protrude from the channel wall 4 into the main channel 1, and the inner wall surfaces B, C, etc. of the curved portion are arranged so as not to protrude from the channel wall 4 into the main channel 1. The corners are rounded.

Next, the operation of the physical quantity measuring device of the present invention will be explained.

The fluid to be measured flowing through the main channel 1 flows from the inlet 2 as shown by the white arrow Y in FIG. It flows out as shown by the black arrow Z.

In the inlet opening 5 in which the inflow direction regulating part 13 is provided, the plurality of plate-shaped or louver-shaped guide pieces 12 constituting the inflow direction regulating part 13 have an angle θ with respect to the flow direction of the main flow path 1 that is larger than 90°. Therefore, even if the fluid to be measured in the main flow path 1 contains minute droplets such as water droplets, the droplets will easily collide with the guide piece 12 and drip or adhere to the guide piece 12. It does not flow into the sub-channel 7 during this time. Further, a similar effect is expected with respect to foreign matter such as dust, such as falling due to collision with the guide piece 12.

Furthermore, since the interval h between the guide pieces 12 is configured such that the relationship with the height H of the main flow path 1 is H>h, the louver-shaped guide pieces 12 When passing through, the large-scale vortices and turbulence of the main stream become small-scale vortices and turbulence, and the turbulence of the flow in the sub-channel 7 becomes smaller than the turbulence in the main channel 1.

In this manner, the state in which liquid droplets such as water droplets in the fluid to be measured are removed and flow turbulence is reduced reduces disturbances in signals during transmission and reception of ultrasonic waves between the ultrasonic transducers 8 and 9. Therefore, the speed of sound can be stably measured using the pair of ultrasonic transducers 8 and 9. The signal processing unit 11 uses the sound velocity obtained in this way and the temperature of the fluid measured by the temperature sensor 10 to calculate the concentration of the component contained in the fluid to be measured using a known method.

In this way, in the sub-channel 7, the intrusion of liquid droplets such as water droplets and foreign matter is greatly suppressed, and a state with little turbulence is achieved, so that liquid such as minute water droplets contained in the fluid to be measured is Even when using a measurement method that is affected by droplets or by disturbances in the flow of the fluid to be measured, it is possible to improve measurement accuracy such as concentration measurement of components contained in the fluid to be measured. Further, since such a configuration does not reduce the cross section of the main flow path 1, no particular pressure loss occurs in the main flow path.

In addition, by arranging a pair of ultrasonic transducers 8 and 9 to face each other in the direction of flow in the sub-channel 7, the length of the straight section of the sub-channel 7, which is the propagation distance, can be adjusted to meet the required measurement accuracy. Furthermore, flow rate measurement can be performed using the reciprocal propagation time difference method.

In the above embodiments of the present invention, the width of the sub-channel 7 (in the depth direction in FIG. 1) has been explained as the entire width W direction of the main channel 1, but as shown in FIG. The sub flow path 7' may have a width W1 which is not the entire width but a part of the width of the long side.

Moreover, although the cross-sectional shape of the main flow path 1 has been described as a channel with a rectangular cross section, it may have a shape other than a rectangular shape, such as a circular cross section. In the case of a circular cross section, if the diameter is D, the relationship between the distance h between the guide pieces 12 and the diameter D is D>h.

Further, although the temperature sensor 10 has been described in the case where it is disposed in the sub-channel 7, it may be disposed in the main channel 1.

In addition, although the description has been made as a physical quantity measuring device that measures the components of a fluid, a flow meter in which a flow rate measuring section is arranged in series on the upstream or downstream side of the main channel 1, or a flow meter that measures the flow rate in the main channel 1 having the sub channel 7 is also used. Needless to say, it can be developed as a flow meter with sections arranged in parallel.

In addition, in this embodiment, the component concentration measuring section is explained as being composed of a pair of ultrasonic transducers 8 and 9, a temperature sensor 10, and a signal processing section 11, but the ultrasonic transducer and temperature sensor A heat flow sensor may be used instead. In addition, for example, a hydrogen sensor or the like that can measure the concentration of a specific gas may be used.

As described above, the physical quantity measuring device of the present invention suppresses the intrusion of droplets into the sub-channel, supplies a stable flow with little turbulence, and provides a measuring device configured to have a configuration with little pressure loss in the main channel. It is possible to realize not only a device for measuring fluid components, but also a flowmeter with high measurement accuracy and versatility by adding a flow rate measurement section.

1 Main channel 4 Channel wall 5 Inlet opening 6 Outlet opening 7 Sub-channel 8, 9 Ultrasonic transducer (component concentration measuring section)
10 Temperature sensor (component concentration measurement section)
11 Signal processing section (component concentration measurement section)
12 Guide piece 13 Inflow direction regulating part

Claims (3)

a main channel through which the fluid to be measured flows;
an inlet opening and an outlet opening provided in a channel wall of the main channel;
a secondary channel connecting the inlet opening and the outlet opening;
an inflow direction regulating section provided at the inlet opening;
a component concentration measuring section disposed in the sub-channel,
The inflow direction regulating portion is configured by arranging a guide piece having a predetermined inclination angle with respect to the flow direction of the main flow path, and the predetermined inclination angle is 90° with respect to the flow direction of the main flow path. The physical quantity measuring device is configured such that the relationship between the distance h between the guide pieces and the height H of the main flow path is H>h. The component concentration measuring section includes:
a pair of ultrasonic transducers disposed in the sub-channel;
a temperature sensor that detects the temperature of the fluid to be measured;
2. The physical quantity measuring device according to claim 1, further comprising a signal processing section that receives signals from the pair of ultrasonic transducers and the temperature sensor and calculates a component concentration of the fluid to be measured. The component concentration measuring section includes:
a heat flow sensor disposed in the sub-channel;
The physical quantity measuring device according to claim 1, further comprising a signal processing section that receives a signal from the heat flow sensor and calculates a component concentration of the fluid to be measured.