JP2000088627A - Method and apparatus for measuring quantity of liq. contg. gas in micro-gravitational environment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure the quantity of a liq. contg. a gas and the gas content by exerting a centrifugal force on a liq. contg. a gas in a microgravitational force into the gas and liq. and measuring their respective quantities in real time. SOLUTION: A liq. 6 contg. a gas is supplied in a rotator 2 via a line 22 having a bend directed to the top or side face of the rotator 2 and moves to the top or side face of the rotator 2 due to the inertial force. Because of the mass difference between the liq. and gas, the moving velocity of the liq. toward the top or side face is higher than that of the gas and stagnates on the side face of the rotator 2 due to the centrifugal force, while the gas remains near the line 22 top end, and the gas mixed in the liq. 4 moves as a gas in a direction 12 due to the specific wt. difference, passes through a separation membrane 15 and discharges from a line 23. When the liq. 4 stagnates on the side face of the rotator 2, a force of an integrated value corresponding to the liq. thickness is exerted on a sensor 8 of a known surface area which then sends a detection signal to a detector 13 to permit the conversion to a pressure, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the amount of liquid containing gas in a microgravity environment and an apparatus used for the method.

[0002]

2. Description of the Related Art Under a microgravity environment such as in a spacecraft flying in orbit around the earth, it is difficult to separate a liquid containing a gas into a liquid into a liquid containing no gas. It is well known.

[0003] The spacecraft includes a living space, a space equipped with devices for testing, and the like. Various types of space and various systems exist for maintaining these spaces and the entire spacecraft. Depending on the type of malfunction that has occurred in these systems, an emergency situation may occur, and failure to cope with the emergency situation may even lead to serious problems affecting the lives of the aviators on board the spacecraft.

[0004] In the prior art, it is difficult to separate and remove a gas mixed in a liquid under a microgravity environment. Therefore, before discussing the good or bad of including a gas in a liquid, all of the gas is removed. I had decided.

[0005] From such a viewpoint, the applicant has previously proposed to remove gas from a liquid containing gas in a microgravity environment. This proposal, when separating from gas-containing liquid into gas and gas-free liquid under microgravity environment,
A gas-liquid separator incorporating at least one unit in which a plurality of hollow fiber membranes are bundled with a plurality of hollow fiber membranes kept at a fixed distance in a wire mesh reinforcing material, and gas is discharged from the hollow fiber membranes constituting the gas-liquid separator The present invention relates to a gas-liquid separation device in a microgravity environment, which comprises a function of measuring a differential pressure and a function of performing self-cleaning.

However, depending on the system, even if a certain amount of gas exists in the liquid, a problem does not always occur. Rather, it is necessary to know for each system how much gas is present in the system system and the problem is likely to occur. The above proposal did not answer this request.

As described above, in order to know how much liquid and gas exist in a system under a microgravity environment, development of a method for measuring a true liquid amount of the entire system and an apparatus used therefor have been awaited. Had been.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to separate a gas-containing liquid into a gas-free liquid and to determine the ratio of gas to liquid present in each system in a microgravity environment. It is an object of the present invention to provide a method for clarifying the amounts of gas and liquid, and a method for measuring the amount of liquid in each system as a whole, and an apparatus used therefor.

[0009]

Means for Solving the Problems The present inventors have made intensive studies in view of the above circumstances. As a result, in a microgravity environment, the gas is difficult to be separated because the specific gravity difference between the liquid and the gas is extremely small.
It has been found that when a nearby centrifugal force is applied, gas is collected in the direction opposite to the given centrifugal force, while liquid is collected in the direction of the centrifugal force, and the gas and liquid are separated. As a result of further intensive studies, the mixed fluid of gas and liquid discharged from the system is separated into gas and liquid by the above means,
It has also been found that by measuring the amounts of the separated gas and liquid in real time, the gas content of the liquid containing gas can be measured.

The present invention has been made in view of the above findings and the above circumstances, and the object of the present invention can be achieved by the following means.

That is, the present invention provides (1) a closed container for separating a gas-containing liquid into a gas and a gas-free liquid in a microgravity environment and measuring the amount of the gas-free liquid; The upper part installed in the inside is opened, the liquid containing gas is introduced into the side of the rotating body provided with the sensor on the side, and the gas collected in the opposite direction to the centrifugal force applied to the side of the rotating body And the liquid that is in contact with the side surface of the rotating body collected in the centrifugal force direction, and the separated gas is sealed so that the separated gas does not come into contact with the rotating body and does not accompany the liquid. Withdrawing from the outlet pipe provided in the container and detecting the amount in real time, on the other hand, separating the separated liquid while controlling the liquid surface formed on the side surface of the rotating body so as not to contact the rotating body, Another derivation provided on the container A method for measuring the amount of liquid containing gas in a microgravity environment in which the amount is extracted in real time and the amount of the liquid is detected in real time. (2) The number of rotations of the rotating body and a sensor provided on a side surface of the rotating body The force corresponding to the amount of the liquid to be measured in real time, the thickness of the liquid surface is detected in real time from these measured values, the volume of the liquid containing gas introduced into the rotating body, the liquid amount The method according to (1), wherein the amount of gas and the amount of liquid extracted from the rotating body are detected in real time while controlling the amount of gas, and the gas content is measured.

The present invention also provides (3) an apparatus for separating a gas-containing liquid into a gas and a gas-free liquid in a microgravity environment and measuring the amount of the gas-free liquid. A function for introducing a liquid containing gas to the side surface of a rotating body provided with a sensor on its side, the upper part of which is installed in a closed vessel, and a centrifugal force applied to the side surface of the rotating body. Gas collected in the direction, and a function for separating the liquid that is in contact with the side surface of the rotating body collected in the centrifugal force direction, so that the separated gas does not contact the rotating body, In addition, a function for extracting the liquid from the outlet pipe provided in the closed container so as not to entrain the liquid and detecting the amount thereof in real time, and controlling the liquid surface formed on the side surface of the rotating body for the separated liquid. Do not touch the rotating body while It is a liquid amount measuring device for liquid containing gas in a microgravity environment having a function for extracting from another outlet pipe provided in the closed container and a function for detecting the liquid amount in real time. (4) a function for real-time measurement of the number of rotations of the rotating body and a force corresponding to a liquid amount applied to a sensor provided on a side surface of the rotating body; A function for detecting the thickness in real time, the volume of the liquid containing the gas introduced into the rotating body, and the amount of gas and liquid extracted from the rotating body while controlling the amount of the liquid are detected in real time. The apparatus according to (3), further having a function of measuring a gas content.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a microgravity environment is defined as 10 g of gravity on the ground (hereinafter referred to as 1G).
⁻² G, more preferably under a gravity environment smaller than 10 ⁻⁴ G.

In the present invention, the centrifugal force applied to the rotating body is preferably 0.1 to 1 times, assuming that the gravity on the earth is 1.
It is a centrifugal force equivalent to 10 times.

In the present invention, examples of the gas include, but are not limited to, an inert gas such as nitrogen, oxygen, air, carbon dioxide, water vapor, and a reaction gas. Examples of the liquid include water, an aqueous solution, a reaction liquid, an aqueous and oily cooling medium, a heating medium, and the like. Here, the types of the reaction gas, the aqueous solution, and the reaction solution are not particularly limited. In short, as a liquid containing gas,
There is no particular limitation as long as the fluid is in a state where gas and liquid are mixed in a microgravity environment.

[0016] Real-time means one continuous per second.
It is time to receive or send a signal several times.

It is needless to say that the situation of the entire system including the transmission and reception of signals can be grasped by displaying the image on a screen of a personal computer or the like as usual.

In the present invention, the system includes, but is not limited to, a cooling / heating system with heat exchange, a reaction system, a temperature / humidity control system, a water regeneration treatment system and a fuel storage system, and a drinking water storage system. A storage system represented by a system or the like can be given.

In the above system, it is also effective if the total amount in the system is known and the purpose is simply to know the gas content.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a flow sheet showing an embodiment of the present invention. Needless to say, the present invention is not limited to this example.

In FIG. 1, system 600 is a cooling and heating system with heat exchange of known total design volume. Although the liquid is normally full in this system by design, it is assumed that gas is mixed for some reason.

The liquid 6 containing gas is discharged from the system 600, and the liquid 6 is guided by the transport function 7 through the line 22 to the sealed container 1. The container 1 is provided with a rotator 2, a rotator 3, a separation membrane 15, a line 22, a line 23 and a line 24. The upper part of the rotating body 2 is partially open (for example, an annular lid is attached to the upper side part). The rotation speed n of the rotator 2 is controlled by the rotator 3. The volume and the rotation speed n of the liquid 6 containing gas per unit time sent by the transport function 7 are determined by the detecting device 1
3 in real time.

The transport function 7 includes a commercially available volume pump, tube pump, rotary pump, gear pump, etc., which makes it easy to check the amount of liquid containing gas, and any of them may be selected.

As described above, the liquid 6 containing gas is supplied to the line 2
2 and is supplied to the inside of the rotating body 2. Here, the tip portion of the line 22 has a curved portion in a space in the rotating body so as to face the upper part or the side surface of the rotating body 2. Therefore, the liquid 6 containing the gas which has not yet been subjected to the centrifugal force under the microgravity moves toward the upper portion or the side surface of the rotating body 2 by the inertial force. Due to the difference in mass between the liquid and the gas, the liquid 6 containing the gas has a much higher moving speed of the liquid toward the upper or side surface of the rotating body 2 than the gas, and the liquid contacts the upper or side surface of the rotating body 2. Rotor 2 affected by centrifugal force
Will accumulate on the sides. Alternatively, the liquid merges with the liquid 4 accumulated on the side surface of the rotating body 2 and the merged liquid is pressed against the side surface of the rotating body 2 by centrifugal force.

On the other hand, the gas is left near the tip of the line 22. The gas mixed in the liquid 4 is
Since the difference in specific gravity from the liquid 4 becomes remarkable, the gas 5
Move to 2. The gas 5 passes through the separation membrane 15 and passes through the line 2
3 and can be separately processed or used. In this way, gas-liquid separation becomes possible.

A description will now be given of the correlation between the centrifugal force received in the rotating body 2 and the rotation speed when separating gas and liquid.

The centrifugal force can be converted into the gravitational acceleration of the rotating body 2 in the radial direction, and usually, kG = 0.01096
It is well known that it is given at 62 rn ² . Here, k, G, r, and n are arbitrarily selectable constants, a gravitational acceleration (9.8 m / s ² ), a radius (m) of the rotating body 2, and a rotation number (rp.
m. ).

Here, assuming that the distance from the center of the rotating body 2 to the liquid amount is r ₅ and the liquid thickness is r ₄ , kG = 0.0109662rn ² = 0.0109662
Since (r ₅ + r ₄ ) n ² , the acceleration gravity differs at each point in the minute section from r ₄ to r. As described above, since the acceleration gravity differs depending on the radial point, it is preferably 0.1 G to 10 G, more preferably 0.1 G to 5 G, and particularly preferably 0.1 G to 5 G.
In the range corresponding to 1 G, it is easy to separate into gas and liquid. If it is less than 0.1 G, it may be difficult for the gas and the liquid to separate, and even if it exceeds 10 G, the effect does not change.
It is preferable to avoid it from the viewpoint of energy consumption.

Hereinafter, the thickness of the liquid 4 accumulated on the side surface of the rotating body 2 and the force applied to the sensor 8 will be described.

A sensor 8 is attached to the side surface of the rotating body 2. The height of the sensor 8 from the side surface of the rotating body 2 is measured in advance, and the measured value is input to the detection device 13.

When the liquid 4 accumulates on the side surface of the rotating body 2,
As described above, a force as an integrated value corresponding to the liquid thickness is applied to the sensor 8 having a known surface area, and the signal is sent to the detection device 13 in real time. In the detection device 13,
Since the surface area corresponding to the liquid amount of the sensor 8 is known and the data on the rotation speed n can be grasped in real time, the integral value of the minute section from r ₄ to r can be calculated from the force applied to the sensor 8. Here, the force applied to the sensor 8 can be converted into pressure or the like. Sensor 8
Is not limited to this, but may be, for example, a commercially available strain gauge.

Hereinafter, a method for maintaining the liquid level remaining on the side surface of the rotating body 2 will be described. As described above, the detection device 13 can calculate the integral value of a minute section from r ₄ to r from the force applied to the sensor 8. Here, the distance from r ₄ to r corresponds to the thickness of the liquid 4. The upper and lower limits of the thickness are input as threshold values to the detection device 13 in advance, and are determined by the determination function H built in the detection device 13.
The determination method during normal operation is controlled by sending a signal to the valve 14 and the transport function 7 so that the liquid level becomes constant within a certain range as is usually performed.

Here, the detection device 13 may be a commercially available personal computer. When the liquid thickness is constantly detected from the sensor 8 and the determination function H, a signal corresponding to the rotation speed n and the liquid thickness is sent from the sensor 8 to the detection device 13 in real time, and the detection device 13 While comparing the signal value with the threshold value corresponding to the lowest liquid level or the highest liquid level, the detection device 13 sends a signal to the valve 14 or the transport function 7 as a signal so as to maintain a constant liquid amount. The quantity is maintained. The signal from the sensing device 13 may be cascaded with the valve 14 and the transport function 7. In addition, it does not prevent controlling the rotation speed n of the rotating body 2 during the normal operation.

As described above, the level of the liquid remaining on the side surface of the rotating body 2 is controlled, and the liquid 4 passes through the line 24 and is extracted as the liquid 10 containing no gas.

The gas 5 and the gas supplied from the line 22 are extracted as a gas 9 from the line 23. Here, at least the rotating body 2
The part inserted in the inside is constituted by a membrane having a property of impervious to liquid but permeating gas. The membrane may be a hollow fiber membrane. For example, a commercially available film made of polyethylene or polypropylene, manufactured by Mitsubishi Rayon Co., Ltd.
What is necessary is just to select from the degassing film-forming module etc. by OK Corporation and Japan Gore-Tex.

A method for measuring the amounts of gas and liquid passing through the lines 23 and 24 will be described. Line 23
Since the line 24 is under a microgravity environment, not all flow meters or flow measurement methods used on the ground can be used. Some flow meters or flow measurement methods include:
Some do not use the Earth's gravity at all and others are not affected by the Earth's gravity. Examples thereof include a positive displacement flowmeter, an electromagnetic flowmeter, an ultrasonic flowmeter, and the like. Also,
The measurement of the minute flow rate includes, for example, a mass flow meter that transfers energy to a fluid and measures the flow rate of the fluid based on the energy amount. All are commercially available, and it is sufficient to select from these. Needless to say, the flow rates of the gas and the liquid are respectively sent to the detection device 13 in real time.

As described above, the gas and liquid withdrawal amounts can be measured, and the gas-containing volume ratio of the liquid 6 containing gas supplied from the line 22 is measured in real time.

Now, the gas separated in the vessel is supplied to line 2
5 while liquid is returned to system 600 via line 26. Needless to say, lines 25 and 26 are at the same pressure. Since the returned gas and liquid are merged, in the system 600 downstream of the junction, the original gas-liquid becomes a mixed phase fluid, and the liquid 6 containing the gas is discharged from the system 600 and the liquid 6 Is guided by the transport function 7 through the line 22 to the sealed container 1. Since such operations are repeatedly performed, if the operation is performed in a steady state, the gas content also falls within a certain range.

In this manner, the true liquid amount stored in the system 600 can be obtained by calculation from the total volume of the system containing gas previously input to the detection device 13 and the gas content. it can.

It should be noted that the gas separated in the vessel may pass through line 25, while the liquid may pass through line 26 and be sent to another system not shown in this figure.

Further, it goes without saying that, in any of the above cases, the gas can be separately processed without being transferred to the system 600.

The response delay τ due to the influence of the gas content and the volume of the line 22 will be described below.

As described above, the volume of the line 22 is a known amount, V ₂₂ , and is input to the detecting device 13. Assuming that V _{6 is} the amount of the liquid 6 containing gas per unit time, y is the volume of the gas in the liquid 6 containing the gas, and x is the volume of the liquid.
It is expressed by gas content = 100y / (x + y).

Here, τ = V ₂₂ / V ₆ and V ₆ = x + y.

The units of V ₂₂ , V ₆ , τ, x and y are m ³ , m ³ / h, h, m ³ and m ³ , respectively.

The response delay will be described. Response delay τ
Are considered by the detection device 13 in real time. Also, as described above, the gas content approaches a certain value,
When the gas content approaches a certain value, it is almost unnecessary to consider the effect of the response delay τ.

[0047]

EXAMPLES The present invention will be described in more detail with reference to the following Examples and Reference Examples, but the present invention is not limited thereto as described above.

Reference Example 1 First, an experiment on the ground was performed according to FIG.
The system 600 has a radius of 0.1 m, a height of 0.5 m, and an internal volume of about 15.7 liters, and when full, the system 600 contains about 14.1 liters of water and 1.
Six liters were stored. Line 25 and line 26
Is provided at the top of the tank of the system 600 and is provided with a gas discharge line and a valve (not shown). The cylindrical rotating body 2 has a radius of 50 mm,
It had an annular lid with a height of 50 mm and a width of 25 mm at the upper part of the side surface, and was housed in a cylindrical, closed container 1 having a radius of 75 mm and a height of 85 mm. The control range of the rotation speed n of the rotator 3 is 10 r. p. m. ~ 1500 r. p. m. Met. The sensor 8 is a differential pressure type liquid level meter, and although not shown in FIG. 1, a signal is wirelessly transmitted from the sensor 8 to the detection device 13. Here, the detection device 13
A commercially available personal computer having a programmable controller was used as the judgment function H. The transport function 7 has a transport volume of 50 cc / min to 500 cc / min. A commercially available tube pump was used. The flow meters provided after the lines 23 and 24 and the valve 14 are mass flow meters, each having a flow rate range of 10 cc / min.
It was 1000 cc / min.

The detecting device 13 receives signals from the transport function 7 and the valve 14 and gives an instruction to them from the judging function H.

Now, so that the gas content of the water stored in the system 600 becomes the liquid 6 containing the gas of 10.2%,
Air was supplied to line 21 from another line not shown in FIG.

As described above, the liquid 6 containing a gas which is non-uniform but has a gas content of 10.2% is supplied from the line 21 to the transport function 7, and is supplied at a rate of 233 cc / min.
To the rotating body 2 through a line 22. Rotating body 2
Is 270 r. p. m. And the thickness of the liquid 4 was controlled in a range of 15 mm ± 2 mm.

The pressure in the line 23 is reduced to 100 mm in water. The flow rate is measured by a gas flow meter through the separation membrane 15 and the line 23, and the measured value is sent to the detecting device 13. The liquid was returned to the system 600 through 25 and discharged through a gas discharge line and a gas discharge valve provided at the top of the tank of the system 600.

The liquid 10 is also supplied from the line 24 to the valve 14
, The flow rate was measured by a liquid flow meter provided downstream, and the measured value was sent to the detection device 13 and returned to the system 600 via the line 26. In the detection device 13,
The gas content was calculated in real time as 10.2% and the liquid volume was controlled.

Example 1 The test under 1 G of Reference Example 1 was conducted in combination with an aircraft test capable of maintaining 10 ⁻² G for about 20 seconds. Specifically, 1G
Lower 10 minutes + Maintain about 10 seconds under 10 ^-2 G + 10 minutes under 1G + 1
It was maintained for about 20 seconds under 0 ^-2 G. The test under 1 G was performed under the same conditions as in Reference Example 1. When the pressure becomes 1 ⁻² G from 1 G, the gas supplied to the transport function 7 from the line 21 in Reference Example 1 is stopped, and the gas discharge line and the gas discharge valve provided at the tank top of the system 600 are closed. The procedure was performed in the same manner as in Reference Example 1 except that the test was carried out in the state described above.

1 supplied to the transport function 7 from the line 21
The liquid 6 containing a gas having a non-uniform gas content of 10.2% under G becomes a liquid 6 containing a gas having a uniform gas content of 10.2% under 10 ^-2 G, The results were the same as those of Reference Example 1 except that the fluid was observed to be separated into gas and liquid. As described above, the result was the same as the ground test result of Reference Example 1.

Example 2 The gas content of 10.2% in Reference Example 1 and Example 1 was changed to 5.
It carried out similarly to Reference Example 1 and Example 1 instead of 0%. It was the same as the ground test result.

Example 3 The gas content of 10.2% in Reference Example 1 and Example 1 was changed to 1.
It carried out similarly to Reference Example 1 and Example 1 instead of 0%. It was the same as the ground test result.

From the above results, it was found that the same effect as on the ground was obtained even under microgravity, suggesting that it is possible to measure the volume of the liquid containing gas stored under microgravity environment. .

[0059]

According to the method and apparatus for removing gas in a liquid under a microgravity environment according to the present invention, (1) In a microgravity environment, a fluid in which a gas and a liquid are mixed in a system includes the gas and the gas. Separate from the liquid and not to know the true liquid amount to be stored, and (2) measure the gas content in real time even if the system contains gas for some reason As a result, the system can be addressed before a problem occurs.

[Brief description of the drawings]

FIG. 1 is a flow sheet showing one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container 2 Rotating body 3 Rotating machine 4 Liquid 5 Gas 6 Liquid containing gas 7 Transport function 8 Sensor 9 Gas 10 Liquid 11, 12 directions 13 Detector 14 Valve 15 Separation membrane 600 System 21-26 Line

Claims (4)

[Claims] In a microgravity environment, a liquid containing a gas is separated into a gas and a liquid containing no gas, and when measuring the amount of the liquid containing no gas, an upper portion installed in a closed container is used. The liquid containing gas is introduced to the side of the rotating body provided with the sensor on its side which is opened, and the gas collected in the direction opposite to the centrifugal force given to the side of the rotating body, in the direction of the centrifugal force. An outlet pipe provided in the closed container so as to separate the collected gas into a liquid that is in contact with the side surface of the rotating body, and separate the separated gas from the rotating body so as not to contact the rotating body and not to accompany the liquid. , The amount of the separated liquid is detected in real time, while the separated liquid is provided in the closed container so as not to contact the rotating body while controlling the liquid surface formed on the side surface of the rotating body. From the outlet pipe of Liquid measurement method of a liquid containing a gas under microgravity environment and detecting the amount in real time. 2. A real-time measurement of the number of rotations of the rotator and a force corresponding to a liquid amount applied to a sensor provided on a side surface of the rotator, and from the measured values, the thickness of the liquid surface is calculated in real time. The volume of the liquid containing gas introduced into the rotating body and the amount of gas and liquid extracted from the rotating body while controlling the amount of liquid are detected in real time to measure the gas content. The method of claim 1. 3. An apparatus for separating a gas-containing liquid into a gas and a gas-free liquid in a microgravity environment and measuring the amount of the gas-free liquid, wherein the apparatus is provided in a closed container. The upper part is opened and a function for introducing a liquid containing gas to the side surface of the rotating body provided with a sensor on the side surface, and the gas collected in the opposite direction to the centrifugal force applied to the side surface of the rotating body. A function for separating the liquid that is in contact with the side surface of the rotating body collected in the centrifugal direction, and a function of separating the separated gas so that the separated gas does not come into contact with the rotating body and does not accompany the liquid. A function for extracting in real time the amount extracted from the outlet pipe provided in the closed container, and contacting the separated liquid with the rotating body while controlling the liquid level formed on the side surface of the rotating body. Avoid the closed container A function for extracting from another outlet pipe provided, liquid measurement apparatus of a liquid containing a gas under microgravity environment characterized by having a function for detecting the liquid volume in real time. 4. A function for measuring in real time the number of rotations of the rotator and a force corresponding to a liquid amount applied to a sensor provided on a side surface of the rotator, and the liquid level is measured from these measured values. Function for detecting the thickness of the in real time, the volume of the liquid containing gas introduced into the rotating body,
The apparatus according to claim 3, further comprising a function of detecting a gas amount and a liquid amount extracted from the rotating body in real time while controlling the liquid amount, and measuring a gas content rate.