JP4586137B2 - Stratospheric aircraft - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a stratospheric flying object such as a balloon or an airship that floats by buoyancy caused by encapsulated buoyant gas.
[0002]
[Prior art]
Scientific observation balloons and unmanned stratospheric airships that are engaged in global environmental monitoring, etc., staying at a high altitude for a long period of time are limited in mission duration because buoyant gas such as hydrogen and helium leaks and gradually decreases.
[0003]
Therefore, the scientific observation balloon liquefies helium gas, puts this liquid helium in a dewar bottle with high heat insulation performance, evaporates liquid helium by electroheating according to the decrease in buoyancy, and gasifies the required amount of helium gas. It is equipped with a buoyancy compensator that recovers buoyancy by placing it in a buoyant gas sac.
[0004]
For example, 1 m ³ liquid helium was proposed in the American Aviation Society paper (AIAA 99-3862, M. Schein et al., An Integrated Cryogen Helium System for Extended Duration Ballots, 1999) published in the United States. The total weight of the buoyancy compensator is 385 kg, of which the weight of liquid helium is 135 kg, the weight of the device alone is 250 kg, and the weight of this device alone is 250 kg. It also includes the weight of the device that liquefies helium gas with electric power and returns it to the Dewar bottle in case the gasification of liquid helium proceeds rapidly due to the heat insulation performance.
When all the liquid helium becomes gas, 740 kg of buoyancy is generated. If the total weight of the device is subtracted, 355 kg of net buoyancy can be recovered, and the power required for this is expected to be about 20-50 W. ing.
[0005]
[Problems to be solved by the invention]
By the way, in the buoyancy compensator as described above, the liquid helium naturally evaporates by heat and increases the pressure. Therefore, the liquid helium must be kept in a dewar with high heat insulation and pressure resistance and a minimum surface area. A container for storing a Dewar bottle made with a design that pays special attention to impact and the like is required, and the weight is considerably increased.
In addition, a helium gas liquefaction device is required in preparation for excessive helium gas liquefaction when the dewar bottle has poor heat insulation or the gas leakage of the balloon or airship is extremely small, so the buoyancy compensator becomes large and heavy. There is a problem of increasing.
[0006]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a stratospheric flying object including a small and light buoyancy compensator.
The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a stratospheric aircraft according to the present invention generates hydrogen gas by electrolysis of water in a fuselage body that is encapsulated with levitation gas and floats by buoyancy by the levitation gas, and supplies the hydrogen gas to the aircraft body. the buoyancy compensator device for compensating the decrease in buoyancy due to the leakage of the levitation gas provided by replenishment to the body, the buoyancy compensator accommodates the bladder to put water for electrolysis into insulated container spherical consisting lightweight material In addition, a heater for preventing freezing of the water is installed in the bladder, and an electrolysis chamber in which water is introduced from the bladder by a pump to perform the electrolysis is installed. A heater and a pressurizer are provided for maintaining the temperature and pressure of the internal water in a state of water that can be electrolyzed, respectively .
In addition, a temperature sensor group for measuring the temperature, pressure, solar radiation, flight position and air speed of the airspace of the above stratosphere aircraft, and the temperature, pressure, and purity of helium gas provided in the helium gas sac A gas sac sensor group for measuring the buoyancy is connected to a microcomputer, and the microcomputer calculates the degree of subsidence or rise of the stratospheric aircraft based on the measurement results of the atmospheric sensor group and the gas sac sensor group. A function to calculate the amount of hydrogen gas required to perform electrolysis of water after the calculation of the degree of decrease in water, and the microcomputer detects water in the electrolysis chamber from the detection results of the water level sensor and the water temperature sensor. In addition to controlling the amount of heat introduced and the amount of heat generated by the heater, it has the function of controlling the pressure in the electrolysis chamber with a pressurizer. It can be assumed to have.
[0008]
Therefore, according to the present invention, the buoyancy is compensated by the hydrogen gas generated by water electrolysis, and the water electrolysis apparatus has a simple apparatus configuration. Therefore, the buoyancy compensation apparatus can be reduced in size and weight, and can be manufactured at low cost and safely. Buoyancy is restored.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the description of the embodiments, the same reference numerals are given to the same functions.
1 is a partially cutaway front view of a stratospheric airship according to an embodiment of the present invention, FIG. 2 is a front view of FIG. 1, and FIG. 3 is a cross-sectional explanatory view of a main part of a buoyancy compensator.
[0010]
The stratosphere airship 1 shown in FIGS. 1 and 2 is a large airship with a body length of 200 to 300 m, and is expected as an electric propulsion stratosphere unmanned platform for streamlined balloons, and is long in the stratosphere at an altitude of about 20 km (mission altitude). It stays for a period of time and is used for survey observation and information relay of the global environment.
[0011]
The stratospheric airship 1 includes a streamlined hull 2 containing a helium gas sac 3 that is a gas barrier film, and a tail wing 4. The helium gas sac 3 is filled with helium gas as a floating gas, and has sufficient strength and rigidity. It consists of a pressurized membrane structure, a bone structure, or a combination thereof, and rises due to the excess buoyancy of helium gas generated by the difference in specific gravity between helium gas and atmospheric pressure, and releases and retains helium gas for the excess buoyancy at the mission altitude.
[0012]
A stern propeller 5 is provided at the stern of the hull 2 so that its rotation axis coincides with the center axis in the front-rear direction of the hull 2 and a propulsion drive motor 6 connected to the rotation axis of the stern propeller 5 is provided internally. The stern propeller 5 is rotated by the propulsion drive motor 6 so that the propulsive force of the stratospheric airship 1 can be obtained.
On the side of the hull 2 from the bow, a ship-side propeller 7 whose rotation axis is substantially perpendicular to the center axis in the front-rear direction of the hull 2 is provided, and the ship-side propeller 7 changes the traveling direction of the hull 2. It is like that.
[0013]
A solar cell panel 8 is stretched on the upper outer periphery of the hull 2, and the electric power generated by the solar cell panel 8 is stored in a battery (not shown), and the stern propeller 5, the ship side propeller 7, Other driving units are driven.
Near the center of the hull 2, an observation / information device 9, a fuel cell 10 and a buoyancy compensator 11, which will be described later, are used for survey and observation of the global environment, communication / broadcasting and disaster monitoring.
[0014]
In the buoyancy compensator 11, as shown in FIG. 3, a thin and lightweight bladder 13 is accommodated in a spherical and lightweight heat insulating container 12, and pure water W is stored in the bladder 13.
An electrolysis chamber 14 is provided in the lower part of the heat insulation container 12, and pure water W in the heat insulation container 12 is introduced into the electrolysis chamber 14 by a pump 15 mounted on the upper part of the electrolysis chamber 14.
An air hole 23 is formed in the upper part of the heat insulating container 12 so that the external air pressure and the air pressure in the heat insulating container 12 become the same pressure, and the temperature of the pure water W is kept constant in the bladder 13 to prevent freezing. The heater 29 is installed.
[0015]
In the electrolysis chamber 14, an anode 16 and a cathode 17 are disposed apart from each other, and a water temperature sensor 18 and a water level sensor 20 for detecting the temperature and level of the pure water W are disposed. A pressurizer 25 and a heater 19 are provided for maintaining the pressure and temperature optimum for electrolysis of the pure water W, respectively.
The upper half portions of the anode 16 and the cathode 17 are respectively located in the gas introduction pipe 21, and the gas introduction pipe 21 on the anode 16 side allows a check valve 22 that allows oxygen gas flow but inhibits reverse flow. The gas introduction tube 21 on the cathode 17 side is connected to the helium gas sac 3 by installing a check valve 22 that allows the flow of hydrogen gas but inhibits the reverse flow. Has been. The anode 16 and the cathode 17 are made of nickel-plated iron plates.
[0016]
Pump 15, anode 16, cathode 17, water temperature sensor 18, heater 19, water level sensor 20, pressurizer 25, gas sac sensor group provided in the helium gas sac 3 and measuring the temperature, pressure, helium purity, etc. of helium gas 24. An atmospheric measurement sensor group 28 for measuring the temperature, pressure and solar radiation of the airspace of the stratosphere airship 1 and the flight position and air speed of the stratosphere airship 1 is connected to the microcomputer 26 and is connected to the solar panel 8 ( Battery) and a DC power supply 27 of the fuel cell 10 are supplied with electric power.
[0017]
The microcomputer 26 calculates the degree of subsidence or rise of the stratospheric airship 1 based on the measurement results of the atmospheric measurement sensor group 28 and the gas sac sensor group 24, calculates the degree of decrease in buoyancy, and then calculates the required amount of hydrogen gas. The amount of pure water W introduced into the electrolysis chamber 14 by the pump 15 and the amount of heat generated by the heater 19 are controlled from the detection results of the water level sensor 20 and the water temperature sensor 18, and the inside of the electrolysis chamber 14 is appropriate. The pressurizer 25 is controlled so as to be a pressure.
[0018]
Since the stratospheric airship 1 is configured as described above, the electrolysis of the pure water W is performed in the electrolysis chamber 14, and the hydrogen gas generated at this time passes through the gas introduction pipe 21 into the helium gas sac 3. The oxygen gas is replenished and discharged from the gas introduction pipe 21 into the atmosphere.
Thus, the buoyancy is increased by replenishment of hydrogen gas, the total weight of the hull 2 is reduced by the decrease of the pure water W due to electrolysis, the decrease in buoyancy due to leakage of the buoyant gas in the stratospheric airship 1 is compensated, and the lost buoyancy. Will recover.
[0019]
In this case, the temperature, pressure, helium purity, and the like in the helium gas sac 3 are measured, and the temperature, pressure, solar radiation, and the like of the airspace are measured. Further, the degree of subsidence or rise of the stratosphere airship 1 is determined by the stratosphere airship 1. The degree of buoyancy reduction is calculated from the position and airspeed. Hydrogen gas is generated according to the buoyancy reduction rate to compensate for buoyancy.
Moreover, if the electric power required for water electrolysis is supplied from the solar cell panel 8 (battery) and / or the fuel cell 10, there is no increase or decrease in the overall weight in the electric power supply system.
When hydrogen gas is mixed with helium gas, it does not explode to a mixing ratio of about 10%. When hydrogen gas is used as a levitation gas, there is no quantitative limitation of the generated hydrogen gas.
[0020]
By the way, considering the amount of hydrogen gas generated by electrolyzing 135 kg of water, 2 mol of water molecules are decomposed into 1 mol of oxygen gas and 2 mol of hydrogen gas. These masses are 32 kg and 4 kg, and the mass ratio of decomposed oxygen gas to hydrogen gas is 8: 1.
[0021]
Therefore, 135 kg of water is divided into a mass of 120 kg of oxygen and a mass of 15 kg of hydrogen. Since hydrogen gas with a mass of 15 kg is 7500 mol, 7500 mol × 22.4 (liter / mol) = 168,000 liter = 168 m ³ (normal temperature and normal pressure).
[0022]
Since the air density is 1.29 kg / m ³ and the density of hydrogen is 0.09 kg / m ³ , the buoyancy (0 ° C) of 168 m ³ of hydrogen in the air is (168 m ³ ) × (1.29-0 0.09) kg / m ³ = 201.6 kg.
Therefore, if the remaining 120 kg of oxygen is discarded, the total weight of water is 135 kg, and apparently 336 kg of buoyancy is generated.
[0023]
As described above, in the present embodiment, pure water W is mounted on the hull 2, and after the pure water W is electrolyzed and separated into hydrogen gas and oxygen gas according to the decrease in buoyancy, the oxygen gas is released into the atmosphere. Since the hydrogen gas is supplied to the helium gas sac 3, the weight of the pure water W is reduced, and the buoyancy is increased by the generation of the hydrogen gas.
[0024]
Now, when a certain amount of liquid is gasified to generate buoyancy, the buoyancy increase is the buoyancy generated by adding the weight of the lost liquid to the buoyancy caused by the generated gas, which is called generated buoyancy. The net recovery buoyancy is the increase in buoyancy when the device is assumed not to exist. Therefore, the water electrolyzer is used as a thin-film bag and the insulation container 12 is a styrofoam (registered by The Dow Chemical Company). If a lightweight material such as a cellular plastic called “trademark” is used, the weight is about 10 kg, and if the weight of the pipe and the controller is 10 kg, the total weight of the gasifier is 155 kg. Since 336 kg of buoyancy is generated, the net buoyancy of about 180 kg can be recovered. 50100
[0025]
Considering a water electrolysis-type buoyancy recovery device such as liquid helium whose weight is equivalent to 385 kg, the relationship between the buoyancy generation capabilities is 385: 155 = x: 336, so the generated buoyancy x = 834 kg. Thus, the generated buoyancy in the case of helium liquefaction greatly exceeds 740 kg. The water electrolyzer, pipe and controller may be further reduced in weight, and the generated buoyancy is considered to be 840 kg or more. The difference from the liquid helium system is clear.
Furthermore, in the water electrolysis apparatus of the present embodiment, water is used as an electrolyte solution, which is advantageous in terms of safety and has a simple apparatus configuration. Therefore, the buoyancy compensation of the stratospheric airship 1 is simple, small, and lightweight. This can be done by the device 11.
[0026]
As mentioned above, although embodiment of this invention was explained in full detail, this invention is not limited to the said embodiment, In the range which does not deviate from the mind of the invention described in the claim of this invention Various changes can be made in the design.
For example, in the above-described embodiment, the pure water W is introduced into the electrolysis chamber 14 by the pump 15 attached to the upper part of the electrolysis chamber 14. The flow rate of the pure water W that naturally falls into the electrolysis chamber 14 may be controlled by an electromagnetic valve.
Moreover, the melting point of the pure water W may be lowered to avoid freezing by adding an antifreezing additive to the pure water W in the bladder 13.
Furthermore, sodium hydroxide or potassium hydroxide may be administered to the pure water W to reduce the electric resistance of the electrolyte and promote electrolysis.
Further, hydrogen gas generated by water electrolysis may be used as fuel for the fuel cell 10.
[0027]
【The invention's effect】
As understood from the above description, according to the present invention, since buoyancy is compensated by hydrogen gas generated by electrolysis of water, there is no need to hold a large amount of cryogenic liquid helium as in the prior art. The water electrolysis device has a simple device configuration and eliminates the water of electrolysis. As a result, the weight of the device is reduced, and the small and light buoyancy compensator improves buoyancy recovery efficiency safely and reliably at low cost. Can be made.
[Brief description of the drawings]
FIG. 1 is a partially cutaway front view of a stratospheric airship showing an embodiment of the present invention.
FIG. 2 is a front view of a stratospheric airship showing an embodiment of the present invention.
FIG. 3 is a cross-sectional explanatory view of a main part of a buoyancy compensator in a stratospheric airship showing an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Stratospheric airship 2 Hull 3 Helium gas sac 4 Tail 5 Stern propeller 6 Propulsion drive motor 7 Ship side propeller 8 Solar panel 9 Observation and information equipment 10 Fuel cell 11 Buoyancy compensator 12 Heat insulation container 13 Bladder 14 Electrolysis chamber 15 Pump 16 Anode 17 Cathode 18 Water temperature sensor 19 Heater 20 Water level sensor 21 Gas introduction pipe 22 Check valve 23 Air hole 24 Gas sac sensor group 25 Pressurizer 26 Microcomputer 27 DC power supply 28 Atmospheric measurement sensor group 29 Heater W Pure water

Claims (3)

Compensation for reduction of buoyancy due to leakage of levitation gas by generating hydrogen gas by electrolysis of water and replenishing the aviation body with hydrogen gas in the fuselage main body that floats by buoyancy by the levitation gas enclosed with levitation gas A buoyancy compensator that
The buoyancy compensator accommodates a bladder in which water for electrolysis is contained in a spherical heat insulating container made of a lightweight material, and a heater for preventing freezing of the water is installed in the bladder. An electrolysis chamber is installed in which water is introduced by a pump and the electrolysis is performed, and the electrolysis chamber includes a heater for maintaining the temperature and pressure of water inside the electrolysable water and Each pressurizer is provided,
A stratospheric aircraft characterized by this. A group of atmospheric measurement sensors that measure the temperature, pressure, solar radiation, flight position and airspeed of the airspace in the stratosphere, and measure the temperature, pressure, and helium purity of the helium gas provided in the helium gas sac. The gas sac sensor group is connected to the microcomputer,
  The microcomputer calculates the degree of subsidence or rise of the stratospheric flying object based on the measurement results of the atmospheric measurement sensor group and the gas sac sensor group, and calculates the degree of decrease in buoyancy. It has a function to calculate the electrolysis of water,
The flying object for stratosphere according to claim 1 characterized by things. The microcomputer has a function of controlling the amount of water introduced into the electrolysis chamber and the heating value of the heater from the detection results of the water level sensor and the water temperature sensor, and controlling the pressure in the electrolysis chamber with a pressurizer. Yes,
The flying object for stratosphere according to claim 2 characterized by things.

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