PHYSICAL QUANTITY MEASUREMENT DEVICE

A physical quantity measurement device is provided which is capable of measuring a component in a fluid to be measured even when the fluid contains droplets such as fine water droplets. The physical quantity measurement device includes, at an inlet opening (5) of a sub-channel (7), an inflow direction regulator (13) which includes guide pieces (12) each of which is inclined at predetermined angle θ with respect to the flow direction in a main channel (1). The angle θ of inflow direction regulator (13) is set to a value that is greater than 90 degrees in relation to the flow direction of the main channel (1).

TECHNICAL FIELD

The present disclosure relates to a physical quantity measurement device which samples part of flowing fluid that is used and measures a physical quantity, such as the concentration, of a component contained in the fluid.

BACKGROUND ART

As a measurement device which measures a fluid component according to a conventional technique, an ultrasonic flowmeter is known which includes a flow rate measurement unit and a component measurement unit which is disposed next to the flow rate measurement unit and which samples fluid flowing through the flow rate measurement unit (for example, Patent Literature (PTL) 1).

FIG.8is a partial cross-sectional view illustrating a configuration of a measurement channel of a component measurement unit included in an ultrasonic flowmeter according to a conventional technique.

In this flowmeter, main channel101of measurement channel100is divided into multiple layers by partition plates102to form multilayer channel103. Sub-channel104for measuring the fluid component is disposed next to multilayer channel103. In order to cause the fluid flowing through main channel101to flow into sub-channel104, protruding portion105protruding to main channel101is disposed on the inlet side of multilayer channel103, and the cross section of the channel is partially reduced in size. Sub-channel104is formed such that the ejector effect generated by the above structure draws the fluid through outlet port106on the upstream side of multilayer channel103ato cause the fluid to flow in through an inlet port (not illustrated).

Subsequently, a gas component is measured by infrared light in this sub-channel104.

CITATION LIST

Patent Literature

SUMMARY OF THE INVENTION

However, in the configuration according to the conventional technique, in cases where the fluid flowing through main channel101contains droplets such as fine water droplets when the fluid in main channel101is drawn to sub-channel104for measuring the fluid component, the droplets enter sub-channel104, which adversely influences the component measurement. Moreover, in order to exert the ejector effect, pressure loss is generated which influences the fluid flowing through main channel101. However, when the pressure loss is reduced, there is a problem that a sufficient suction force to cause the fluid to flow into sub-channel104cannot be obtained.

The present disclosure is capable of providing a measurement device which significantly reduces entrance of droplets such as water droplets into a sub-channel for measuring characteristics, such as the concentration, of a component contained in the fluid and also accurately measures the concentration of the component contained in the fluid in the sub-channel while reducing the turbulence of the fluid flow generated in the main channel.

A physical quantity measurement device according to the present disclosure includes: a main channel through which a fluid to be measured flows; an inlet opening and an outlet opening which are provided in a channel wall of the main channel; a sub-channel which connects the inlet opening and the outlet opening; an inflow direction regulator which is disposed at the inlet opening; a chamber portion which is disposed in the sub-channel; a pair of ultrasonic transmitter and receiver which are disposed in the chamber portion; a temperature sensor which detects a temperature of the fluid; and a signal processor which calculates a concentration of a component contained in the fluid in response to a signal from the pair of ultrasonic transmitter and receiver and a signal from the temperature sensor. The inflow direction regulator includes a guide piece which is inclined at a predetermined angle with respect to a flow direction of the fluid in the main channel. The predetermined angle is set to a value that is greater than 90 degrees in relation to the flow direction of the fluid in the main channel. The chamber portion has a cross-sectional area that is greater than an effective cross-sectional area of the inlet opening. Even when the fluid to be measured contains droplets such as fine water droplets, the physical quantity measurement device thus configured is capable of supplying, to the sub-channel, fluid in which the mixture of droplets such as water droplets is significantly reduced and which contains substantially no droplets. With this, it is possible to significantly reduce the influence of droplets and the like, and to increase the accuracy of measurement such as the concentration measurement of a component contained in the fluid. Moreover, since in the chamber portion disposed in the sub-channel, the inflow velocity of the fluid can be reduced, the disturbance of the fluid generated in the main channel can be reduced. With this, it is possible to measure, in the sub-channel, the fluid to be measured in a state where the disturbance of the fluid flow is small. Moreover, the main channel of the physical quantity measurement device has a cross-sectional area that is not reduced in the portion where the fluid flowing through the main channel is led to the sub-channel. Hence, no particular pressure loss is generated in the fluid flowing through the main channel.

Moreover, a physical quantity measurement device according to the present disclosure includes: a main channel through which a fluid to be measured flows; an inlet opening and an outlet opening which are provided in a channel wall of the main channel; a sub-channel which connects the inlet opening and the outlet opening; an inflow direction regulator which is disposed at the inlet opening; and a component concentration measurement unit which is disposed in the sub-channel. The inflow direction regulator includes a plurality of guide pieces each of which is inclined at a predetermined angle with respect to a flow direction of the fluid in the main channel. The predetermined angle is set to a value that is greater than 90 degrees in relation to the flow direction of the fluid in the main channel, and a relation between a distance h and a height H satisfies H>h where the distance h is a distance between adjacent ones of the plurality of guide pieces and the height H is a height of the main channel. Even when the fluid to be measured contains droplets such as fine water droplets, the physical quantity measurement device thus configured is capable of supplying, to the sub-channel, fluid in which the mixture of droplets such as water droplets is significantly reduced and which contains substantially no droplets. With this, it is possible to significantly reduce the influence of droplets and the like, and to increase the accuracy of measurement such as the concentration measurement of a component contained in the fluid. Moreover, by dividing the flow of the fluid by louver-shaped guide pieces, it is possible to reduce the disturbance of the flow of the fluid generated in the main channel. With this, it is possible to measure, in the sub-channel, the fluid to be measured in a state where the disturbance of the fluid flow is small. Moreover, the main channel of the physical quantity measurement device has a cross-sectional area that is not reduced in the portion where the fluid flowing through the main channel is led to the sub-channel. Hence, no particular pressure loss is generated in the fluid flowing through the main channel.

The physical quantity measurement device according to the present disclosure includes an inflow direction regulator which is disposed at the inlet opening. The inflow direction regulator includes guide pieces each of which is inclined at a predetermined angle with respect to the flow direction of the fluid in the main channel. The predetermined angle is set to a value that is greater than 90 degrees in relation to the flow direction of the fluid in the main channel. Even when the fluid to be measured contains droplets such as fine water droplets, the physical quantity measurement device thus configured is capable of supplying, to the sub-channel, fluid in which the mixture of droplets such as water droplets is significantly reduced and which contains substantially no droplets. With this, it is possible to significantly reduce the influence of droplets and the like, and to increase the accuracy of measurement such as the concentration measurement of a component contained in the fluid. Moreover, since the inflow velocity of the fluid can be reduced in the chamber portion disposed in the sub-channel, the disturbance of the fluid generated in the main channel can be reduced. With this, it is possible to measure, in the sub-channel, the fluid to be measured in a state where the disturbance of the fluid flow is small. Moreover, the cross-sectional area of the main channel is not reduced in the portion where the fluid flowing through the main channel is led to the sub-channel. Hence, no particular pressure loss is generated in the fluid flowing through the main channel.

Moreover, by dividing the flow of the fluid by louver-shaped guide pieces, it is possible to reduce the disturbance of the flow of the fluid generated in the main channel. With this, it is possible to measure, in the sub-channel, the fluid to be measured in a state where the disturbance of the fluid flow is small. Moreover, the cross-sectional area of the main channel is not reduced in the portion where the fluid flowing through the main channel is led to the sub-channel. Hence, no particular pressure loss is generated in the fluid flowing through the main channel.

DESCRIPTION OF EMBODIMENTS

However, more detailed explanations than necessary may be omitted. For example, detailed explanations of already well-known matters or duplicate explanations for substantially the same configuration may be omitted.

It should be noted that the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter recited in the claims.

First Embodiment

A first embodiment will be described with reference toFIG.1andFIG.2.

FIG.1is a cross-sectional view illustrating an example of a configuration of a physical quantity measurement device according to the first embodiment.FIG.2is a cross-sectional view taken along line A-A ofFIG.1.

InFIG.1andFIG.2, main channel1through which fluid to be measured (hereinafter, also simply referred to as “fluid”) flows is a circular channel having a cross section with diameter D. Main channel1includes inlet2and outlet3.

Channel wall4of main channel1includes inlet opening5on the upstream side, and outlet opening6which is provided downstream of inlet opening5. Sub-channel7which connects inlet opening5and outlet opening6is disposed in parallel with main channel1. Sub-channel7includes chamber portion7athat is positioned closer to inlet opening5and channel portion7bthat is positioned downstream of chamber portion7a.

A pair of ultrasonic transmitter8and receiver9, which transmit an ultrasonic signal to the fluid to be measured and receive the ultrasonic signal, are disposed in chamber portion7aof sub-channel7. Temperature sensor10which detects the temperature of the fluid is disposed in main channel1.

The pair of ultrasonic transmitter8and receiver9and temperature sensor10are electrically connected to signal processor11(not illustrated). Signal processor11calculates the component concentration of the fluid to be measured in response to the signals from the pair of ultrasonic transmitter8and receiver9and temperature sensor10.

Inflow direction regulator13is disposed at inlet opening5of sub-channel7. Inflow direction regulator13includes a plurality of plate-shaped or louver-shaped guide pieces12each of which is inclined at predetermined angle θ with respect to the flow direction of the fluid in main channel1. Predetermined angle θ of each guide piece12is set to a value that is greater than 90 degrees as illustrated inFIG.1in relation to the flow direction of the fluid in main channel1(that is, from the downstream side to the upstream side of main channel1).

The pair of ultrasonic transmitter8and receiver9in sub-channel7are arranged so as to oppose to each other in a direction substantially orthogonal to fluid flow Ff in sub-channel7, and disposed in chamber portion7athat is positioned on the upstream side of sub-channel7.

Chamber portion7aof sub-channel7in which ultrasonic transmitter8and receiver9are disposed has a cross-sectional area that is greater than the substantial cross-sectional area (effective cross-sectional area) of the portion of inlet opening5through which the fluid flows.

Inflow direction regulator13is arranged so as not to protrude from channel wall4to main channel1. Inner wall surfaces B, C, etc. of the curved portions of sub-channel7have corners R (rounding) so as to smooth the fluid flow.

Next, an operation of the physical quantity measurement device according to the present embodiment will be described.

The fluid to be measured flowing through main channel1flows in through inlet2as indicated by white arrow Y inFIG.1. Most of the fluid flowing through main channel1becomes flow Fm, and finally flows out through outlet3as indicated by black arrow Z inFIG.1.

In inlet opening5where inflow direction regulator13is disposed, each of plate-shaped or louver-shaped guide pieces12of inflow direction regulator13is set to have angle θ that is greater than 90 degrees with respect to the flow direction of the fluid in main channel1. With this, even when the fluid to be measured in main channel1contains fine droplets such as water droplets, the water droplets collide with guide pieces12and drop or adhere to guide pieces12, preventing the water droplets from flowing into sub-channel7.

Flow Ff of the fluid flowing from main channel1into sub-channel7in such a manner is smoothed by corners R (rounding) disposed at the curved portions, and flows out to main channel1through outlet opening6.

Accordingly, the fluid with a component concentration to be measured in sub-channel7enters chamber portion7aof sub-channel7in a state where droplets such as water droplets are substantially removed. In addition, since chamber portion7ahas a cross-sectional area that is greater than the effective cross-sectional area of inlet opening5, the flow velocity of the fluid passing through guide pieces12decreases in chamber portion7a,so that the turbulence of the flow generated in main channel1is reduced.

As described above, droplets, such as water droplets, are substantially removed from the fluid to be measured and the turbulence of the flow is reduced, so that the disturbance of the signal generated when ultrasonic waves are transmitted and received between ultrasonic transmitter8and receiver9can be reduced. As a result, the sound velocity of the fluid to be measured can be stably measured by using the pair of ultrasonic transmitter8and receiver9. Signal processor11calculates the concentration of a component contained in the fluid to be measured by a known method using the sound velocity thus obtained and the temperature of the fluid measured by temperature sensor10.

Moreover, by arranging the pair of ultrasonic transmitter8and receiver9so as to oppose to each other in the direction orthogonal to the flow of the fluid to be measured in sub-channel7, the size of sub-channel7can be reduced, leading to downsizing of the physical quantity measurement device.

As described above, in sub-channel7, it is possible to significantly reduce the mixture of droplets such as water droplets into the fluid to be measured flowing through sub-channel7, and to achieve a fluid flow state with a small turbulent. Accordingly, the physical quantity measurement device including sub-channel7is capable of increasing the accuracy of the measurement, such as the measurement of the concentration of a component contained in the fluid to be measured. Additionally, in this physical quantity measurement device, since the cross section of main channel1is not reduced in size, no particular pressure loss is generated in the fluid flowing through main channel1.

Second Embodiment

A second embodiment will be described with reference toFIG.3andFIG.4.

FIG.3is an external perspective view illustrating an example of a configuration of a physical quantity measurement device according to the second embodiment.FIG.4is an exploded assembly view illustrating an example of structural elements of the physical quantity measurement device illustrated inFIG.3.

In the present embodiment, the structural elements having the same functions as those in the first embodiment are assigned with the same reference numbers, and the description thereof will be omitted.

Signal processor11is disposed on signal processor mounting portion15bof sub-channel housing block15, and is fixed to sub-channel housing block15with the upper side of signal processor11being covered with protection block18.

Temperature sensor10is assembled to temperature sensor mounting portion14dof main channel housing block14via an airtight sealing member (not illustrated) such as an O-ring.

As described above, in the physical quantity measurement device according to the present embodiment, sub-channel housing block15which houses sub-channel forming block17that is integrally formed with inflow direction regulator13is assembled to main channel housing block14including main channel1. With such a configuration of the physical quantity measurement device, the size of the sub-channel can be further reduced, and the productivity at the time of the production of the physical quantity measurement device can be increased by reducing the step of providing, in the main channel, a device for measuring the physical quantity of fluid flowing through the main channel. Moreover, a reduced number of components included in the physical quantity measurement device leads to a cost reduction at the time of producing the physical quantity measurement device.

Although it has been described in the first and second embodiments that the cross-sectional shape of main channel1is circular, the physical quantity measurement device according to the present disclosure is not limited to such an example. The cross-sectional shape of main channel1may be a shape other than a circle, such as a rectangle. Moreover, although it has been described in the first and second embodiments that temperature sensor10is disposed in main channel1, temperature sensor10may be disposed in sub-channel7.

Moreover, although it has been described in the first and second embodiments that the physical quantity measurement device is a device for measuring a component of the fluid, the physical quantity measurement device according to the present disclosure is not limited to such an example. The physical quantity measurement device according to the present disclosure may be a flowmeter in which a flow rate measurement unit is disposed in series with the upstream side or the downstream side of main channel1, or a flowmeter in which a flow rate measurement unit is disposed in parallel with main channel1including sub-channel7.

Third Embodiment

A third embodiment will be described with reference toFIG.5andFIG.6. A physical quantity measurement device according to the third embodiment includes substantially the same functions as the physical quantity measurement devices according to the first and second embodiments, but there are some differences. The differences will be described below.

FIG.5is a cross-sectional view illustrating an example of a configuration of a physical quantity measurement device according to the third embodiment.FIG.6is a cross-sectional view taken along line A-A ofFIG.5.

InFIG.5andFIG.6, main channel201through which fluid to be measured (hereinafter, also simply referred to as “fluid”) flows is a rectangular channel that has a cross-sectional shape with a long side that is width W and a short side that is height H. Main channel201includes inlet202and outlet203.

Channel wall204of main channel201includes inlet opening205on the upstream side. Outlet opening206is provided downstream of inlet opening205. Sub-channel207which connects inlet opening205and outlet opening206is disposed in parallel with main channel201. In sub-channel207, a pair of ultrasonic transmitter208and receiver209arranged opposing to each other along the fluid flowing direction (that is, on the upstream side and the downstream side), and temperature sensor210which detects the temperature of the fluid are disposed.

The pair of ultrasonic transmitter208and receiver209and temperature sensor210are electrically connected to signal processor211. Signal processor211calculates the component concentration of the fluid in response to the signals from the pair of ultrasonic transmitter208and receiver209and temperature sensor210.

In the present embodiment, the component concentration measurement unit includes the pair of ultrasonic transmitter208and receiver209, temperature sensor210, and signal processor211.

At inlet opening205of sub-channel207, inflow direction regulator213is disposed which includes a plurality of plate-shaped or louver-shaped guide pieces212each of which is inclined at predetermined angle θ with respect to the flow direction of the fluid in main channel201. Each guide piece212is inclined at angle θ that is set to a value greater than 90 degrees as illustrated inFIG.5, in relation to the flow direction of the fluid in main channel201(that is, from the downstream side to the upstream side of main channel201).

Guide pieces212are configured to satisfy the relation of H>h where h is a distance between adjacent guide pieces212and H is a height of main channel201. Here, distance h between guide pieces212and height H of the main channel are values corresponding to the characteristic length of the Reynolds number.

Inflow direction regulator213is disposed so as not to protrude from channel wall204to main channel201. Inner wall surfaces B, C, etc. of the curved portions of sub-channel207have corners R (rounding) so as to smooth the fluid flow.

Next, an operation of the physical quantity measurement device according to the present embodiment will be described.

The fluid to be measured flowing through main channel201flows in through inlet202as indicated by white arrow Y inFIG.5. Most of the fluid flowing through main channel201becomes flow Fm, and finally flows out through outlet203as indicated by black arrow Z inFIG.5.

At inlet opening205where inflow direction regulator213is disposed, each of a plurality of plate-shaped or louver-shaped guide pieces212of inflow direction regulator213has angle θ set to a value that is greater than 90 degrees with respect to the flow direction of the fluid in main channel201. With this, even when the fluid to be measured in main channel201contains fine droplets such as water droplets, the droplets collide with guide pieces212and drop or adhere to guide pieces212, preventing the droplets from flowing into sub-channel207. Moreover, with respect to foreign substances such as dust, the same advantageous effects as those for droplets can be obtained by collision with guide pieces212and dropping or the like.

Guide pieces212are configured to satisfy the relation of H>h where h is a distance between adjacent guide pieces212and H is a height of main channel201. With this configuration, when the fluid passes louver-shaped guide pieces212, large-scale vortices and turbulence generated in the fluid flowing through main channel201becomes smaller. Moreover, the turbulence of the fluid flow in sub-channel207is smaller than the turbulence of the fluid flow in main channel201.

In this way, droplets such as water droplets are substantially removed from the fluid to be measured and the turbulence of the flow is reduced, so that the disturbance of the signal generated when ultrasonic waves are transmitted and received between ultrasonic transmitter208and receiver209can be reduced. With this, the sound velocity of the fluid to be measured can be stably measured by using the pair of ultrasonic transmitter208and receiver209. Signal processor211calculates the concentration of a component contained in the fluid to be measured by a known method using the sound velocity thus obtained and the temperature of the fluid measured by temperature sensor210.

In this way, in sub-channel207, it is possible to significantly reduce the mixture of droplets such as water droplets and foreign substances into the fluid to be measured flowing through sub-channel207, and to achieve a fluid flow state with a small turbulence. Accordingly, in the physical quantity measurement device which includes sub-channel207, even when a measurement method is used which is influenced by droplets such as fine water droplets contained in the fluid to be measured or which is influenced by the turbulence of the flow of the fluid to be measured, it is possible to reduce the influences and increase the accuracy of measurement such as the concentration measurement of a component contained in the fluid to be measured. Moreover, in the physical quantity measurement device thus configured, since the cross section of main channel201is not reduced in size, no particular pressure loss is generated in the fluid flowing through main channel201.

Moreover, by arranging the pair of ultrasonic transmitter208and receiver209so as to oppose to each other along the direction of the flow of the fluid in sub-channel207(that is, on the upstream side and on the downstream side), the length of the straight portion of sub-channel207, which is the propagation distance of ultrasonic waves, can be increased in accordance with the required measurement accuracy. In addition, the flow rate measurement using a propagation time reciprocal difference method can also be performed.

Although it has been described in the third embodiment that, as illustrated inFIG.6, the width of sub-channel207(depth direction ofFIG.5) is equal to width W of main channel201, the present disclosure is not limited to such an example.FIG.7illustrates another shape of a cross section taken along line A-A line ofFIG.5. For example, as illustrated inFIG.7, sub-channel207′ with width W1that is narrower than width W may be disposed in place of sub-channel207.

Moreover, although it has been described in the third embodiment that the cross-sectional shape of main channel201is rectangle, the physical quantity measurement device according to the present disclosure is not limited to such an example. The cross-sectional shape of main channel201may be a shape other than a rectangle such as a circle. When the cross-sectional shape of main channel201is circle and the diameter of the circle is D, the relation between diameter D and distance h that is a distance between adjacent guide pieces212satisfies D>h.

Moreover, although it has been described in the third embodiment that temperature sensor210is disposed in sub-channel207, temperature sensor210may be disposed in main channel201.

Moreover, although it has been described in the third embodiment that the physical quantity measurement device is a device for measuring a component of the fluid, the physical quantity measurement device according to the present disclosure is not limited to such an example. The physical quantity measurement device according to the present disclosure may be a flowmeter in which a flow rate measurement unit is disposed in series with the upstream side or the downstream side of main channel201, or a flowmeter in which a flow rate measurement unit is disposed in parallel with main channel201including sub-channel207.

Moreover, it has been described in the third embodiment that the component concentration measurement unit includes the pair of ultrasonic transmitter208and receiver209, temperature sensor210, and signal processor211. However, the physical quantity measurement device according to the present disclosure is not limited to such an example. The physical quantity measurement device according to the present disclosure may include a heat flow sensor in place of the ultrasonic transmitter and receiver and the temperature sensor. Alternatively, a sensor capable of measuring the concentration of a specific gas, for example, a hydrogen sensor, may be used.

As described above, a physical quantity measurement device according to a first disclosure includes: a main channel through which a fluid to be measured flows; an inlet opening and an outlet opening which are provided in a channel wall of the main channel; a sub-channel which connects the inlet opening and the outlet opening; an inflow direction regulator which is disposed at the inlet opening; a chamber portion which is disposed in the sub-channel; a pair of ultrasonic transmitter and receiver which are disposed in the chamber portion; a temperature sensor which detects a temperature of the fluid; and a signal processor which calculates a concentration of a component contained in the fluid in response to a signal from the pair of ultrasonic transmitter and receiver and a signal from the temperature sensor. The inflow direction regulator includes a guide piece which is inclined at a predetermined angle with respect to a flow direction of the fluid in the main channel. The predetermined angle is set to a value that is greater than 90 degrees in relation to the flow direction of the fluid in the main channel. The chamber portion has a cross-sectional area that is greater than an effective cross-sectional area of the inlet opening. Even when the fluid to be measured contains droplets such as fine water droplets, the physical quantity measurement device thus configured is capable of supplying, to the sub-channel, the fluid in which the mixture of droplets such as water droplets is significantly reduced and the droplets are substantially removed. With this, even when the fluid to be measured contains fine water droplets and the like, the influence of such water droplets is significantly reduced, and the accuracy of measurement, such as concentration measurement of a component contained in the liquid can be increased. Moreover, since the inflow velocity of the fluid in the chamber portion that is disposed in the sub-channel can be reduced, the disturbance of the fluid flow generated in the main channel can be reduced. With this, it is possible to measure, in the sub-channel, the fluid to be measured in a state where the disturbance of the fluid flow is small. Moreover, the main channel of the physical quantity measurement device has a cross-sectional area that is not reduced in the portion where the fluid flowing through the main channel is led to the sub-channel. Hence, no particular pressure loss is generated in the fluid flowing through the main channel.

In the physical quantity measurement device according to a second disclosure, the main channel includes a main channel housing block which penetrates the main channel in the physical quantity measurement device according to the first disclosure. The sub-channel which connects the inlet opening and the outlet opening includes a sub-channel housing block which houses a sub-channel forming block. The inflow direction regulator is integrally formed with the sub-channel forming block. The sub-channel housing block which houses the sub-channel forming block is assembled to the main channel housing block. With such a configuration of the physical quantity measurement device, the size of the sub-channel can be further reduced, and the productivity at the time of the production of the physical quantity measurement device can be increased by reducing the step of providing, in the main channel, a device for measuring the physical quantity of fluid flowing the main channel. Moreover, a reduced number of components included in the physical quantity measurement device leads to a cost reduction at the time of producing the physical quantity measurement device.

A physical quantity measurement device according to a third disclosure includes: a main channel through which a fluid to be measured flows; an inlet opening and an outlet opening which are provided in a channel wall of the main channel; a sub-channel which connects the inlet opening and the outlet opening; an inflow direction regulator which is disposed at the inlet opening; and a component concentration measurement unit which is disposed in the sub-channel. The inflow direction regulator includes a plurality of guide pieces each of which is inclined at a predetermined angle with respect to a flow direction of the fluid in the main channel. The predetermined angle is set to a value that is greater than 90 degrees in relation to the flow direction of the fluid in the main channel, and a relation between a distance h and a height H satisfies H>h where the distance h is a distance between adjacent ones of the plurality of guide pieces and the height H is a height of the main channel. Even when the fluid to be measured contains droplets such as fine water droplets, the physical quantity measurement device thus configured is capable of supplying, to the sub-channel, the fluid in which the mixture of droplets such as water droplets is significantly reduced and which contains substantially no droplets. With this, it is possible to significantly reduce the influence of droplets and the like, and to increase the accuracy of measurement such as the concentration measurement of a component contained in the fluid. Moreover, by dividing the fluid flow by louver-shaped guide pieces, it is possible to reduce the disturbance of the flow of the fluid generated in the main channel. With this, it is possible, in the sub-channel, to measure the fluid to be measured in a state where the disturbance of the fluid flow is small. Moreover, in the physical quantity measurement device, the cross-sectional area of the main channel is not reduced in the portion where the fluid flowing through the main channel is led to the sub-channel. Hence, no particular pressure loss is generated in the fluid flowing through the main channel.

In the physical quantity measurement device according to a fourth disclosure, the component concentration measurement unit includes: a pair of ultrasonic transmitter and receiver which are disposed in the sub-channel; a temperature sensor which detects a temperature of the fluid; and a signal processor which calculates a concentration of a component contained in the fluid in response to a signal from the pair of ultrasonic transmitter and receiver and a signal from the temperature sensor, particularly in the physical quantity measurement device according to the third embodiment.

In the physical quantity measurement device according to a fifth disclosure, the component concentration measurement unit includes: a heat flow sensor which is disposed in the sub-channel; and a signal processor which calculates a concentration of a component contained in the fluid in response to a signal from the heat flow sensor, particularly in the physical quantity measurement device according to the third disclosure.

INDUSTRIAL APPLICABILITY

As described above, the present disclosure provides a physical quantity measurement device which is capable of preventing droplets from entering the sub-channel, supplying a stable fluid flow with a small disturbance to the sub-channel, and generating little pressure loss in the main channel. With this, it is possible to provide a flowmeter, which includes not only a measurement device which measures a component of fluid but also a flow rate measurement unit disposed next to the measurement device, with a high measurement accuracy and high general versatility.

REFERENCE MARKS IN THE DRAWINGS

8,9ultrasonic transmitter and receiver

14main channel housing block

14dtemperature sensor mounting portion

15sub-channel housing block

15aultrasonic transmitter mounting portion

15bsignal processor mounting portion

17sub-channel forming block

208,209ultrasonic transmitter and receiver (component concentration measurement unit)