JP2004095506A - Freezable liquid storage tank - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact freezable liquid storage tank capable of quickly thawing frozen liquid. <P>SOLUTION: A heating means 17 is arranged at the periphery 13 of the tank 11 at least including the bottom part 12, and a vibrating means 50 adding vibration to the partially thawed liquid W is installed. Since the frozen liquid W is used after thawing by the heating means 17 and the vibrating means 50 when the stored liquid W is frozen, a convection of the liquid W thawed by the heating means 17 at the bottom part 12 is generated, and the frozen liquid W around the convection part is promoted to be thawed. The frozen liquid W is further promoted to be thawed by compulsorily adding vibration to the partially thawed liquid W by the vibrating means 50. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a storage tank for a liquid that can be frozen and used when the stored liquid is frozen.
[0002]
[Prior art]
In the fuel cell system disclosed in JP-A-2000-149970, air is supplied to the air electrode of the fuel cell main body through a humidifier, and hydrogen extracted from methanol by a fuel reformer is supplied to the fuel electrode. In addition, electricity is extracted by chemically reacting oxygen and hydrogen in the air.
[0003]
At this time, the water stored in the water tank is supplied to the humidifier and the fuel reformer, and the humidifier sprays water on the air supplied to the fuel cell body, and The vessel reacts methanol and water at a high temperature to generate hydrogen gas.
[0004]
[Problems to be solved by the invention]
However, if the water stored in the water tank freezes during cold weather or the like, water cannot be supplied to the humidifier and the fuel reformer, so that the fuel cell system cannot be started.
[0005]
For this reason, in the fuel cell system, an auxiliary tank having a heater is provided in the water tank, and when the water is frozen, at the time of starting, the frozen water is melted by the heater, and the water melted from the auxiliary tank is humidified. And a fuel reformer.
[0006]
However, merely warming the frozen water with a heater would slow the rate of melting of the frozen water and make it impossible to supply sufficient water.As a result, the fuel cell startup timing must be adjusted to obtain the required amount of water at startup. Smooth operation of the fuel cell is hindered because it needs to be delayed.
[0007]
Further, the provision of the auxiliary tank complicates and enlarges the structure of the water tank, making it difficult to reduce the size of the fuel cell system.
[0008]
Accordingly, the present invention has been made to solve such a conventional problem, and it is an object of the present invention to provide a storage tank for a liquid that can be frozen so that the frozen liquid can be thawed more quickly while reducing the overall size. With the goal.
[0009]
[Means for Solving the Problems]
In the invention according to claim 1, when the stored liquid is frozen, the frozen liquid is thawed.
A heating means is provided around at least the bottom of the tank container, and a vibrating means for applying vibration to the partially melted liquid is provided.
[0010]
According to the second aspect of the present invention, in the storage tank for a liquid that can be frozen according to the first aspect, a fin that transmits heat of the heating means is provided in a vertical direction inside a tank container. And
[0011]
According to the third aspect of the present invention, in the storage tank for a liquid that can be frozen according to the first or second aspect, the tank container is provided with a volume change permitting unit that allows a volume change when the liquid is frozen. Features.
[0012]
According to a fourth aspect of the present invention, in the freezing liquid storage tank according to any one of the first to third aspects, the vibrating means is provided at a bottom of the tank container.
[0013]
In the invention according to claim 5, in the storage tank for a liquid that can be frozen according to any one of claims 1 to 4, the heating means has a double wall structure at least around the bottom of the tank container. It is characterized by a passage for circulating a fluid.
[0014]
According to a sixth aspect of the present invention, in the storage tank for a liquid capable of being frozen according to the fifth aspect, a vibrating means is provided at a bottom portion of the tank container where the liquid is stored, and vibrates due to pulsation of the introduced heating fluid. It is characterized in that it is a vibrating member.
[0015]
According to a seventh aspect of the present invention, in the storage tank for a liquid that can be frozen according to the sixth aspect, a vibrating means is provided near the inlet for introducing the heating fluid into the tank container. It is characterized by the means.
[0016]
In the invention according to claim 8, in the storage tank for a liquid that can be frozen according to claim 6 or 7, the vibrating means includes a voltage changing means for changing a driving voltage of a circulation pump for flowing the heating fluid. It is characterized by doing.
[0017]
According to the ninth aspect of the present invention, in the storage tank for a liquid that can be frozen according to any one of the first to eighth aspects, a heating element is provided in a suction pipe of a liquid pump that suctions the melted liquid. It is characterized by.
[0018]
According to a tenth aspect of the present invention, in the storage tank for a freezing liquid according to the ninth aspect, an ice block preventing means for blocking passage of an ice block having a predetermined size or more is provided in the suction pipe. Features.
[0019]
【The invention's effect】
According to the first aspect of the present invention, since the heating means is provided on the periphery including at least the bottom of the tank container, the heat from the heating means is applied to the frozen liquid from the periphery to increase the melting speed, and provided on the bottom. The convection of the liquid melted by the heating means can be generated to promote the melting of the frozen liquid around the convection portion.
[0020]
Further, by applying vibration to the liquid partially melted by the vibrating means, the molten liquid can be forcibly vibrated to further promote the melting of the surrounding frozen liquid.
[0021]
According to the second aspect of the present invention, in addition to the effect of the first aspect, since the inside of the frozen liquid can be heated from the inside of the frozen liquid by the fin that transfers the heat of the heating means, the melting of the frozen liquid is accelerated, By providing the fins in the vertical direction, the molten liquid can be largely convected naturally to promote the melting of the frozen liquid.
[0022]
According to the third aspect of the invention, in addition to the effects of the first and second aspects of the invention, the volume change when the frozen liquid expands in the tank container can be absorbed by the volume change permitting means. It is possible to suppress an excessive outward pressing force from acting on the container and to prevent the tank container from being damaged.
[0023]
According to the fourth aspect of the invention, in addition to the effects of the first to third aspects, the molten liquid is vibrated up and down by vibrating means provided at the bottom of the tank container to generate forced convection. Therefore, the surrounding liquid can be thawed more quickly.
[0024]
According to the fifth aspect of the invention, in addition to the effects of the first to fourth aspects, since the surroundings including the bottom of the portion storing the liquid in the tank container can be uniformly heated by the heating fluid, the frozen liquid Can uniformly apply heat energy to portions that come into contact with the passage in which the heating fluid circulates, thereby accelerating the melting.
[0025]
According to the invention of claim 6, in addition to the effect of the invention of claim 5, a large vibration energy due to pulsation of the heating fluid is added to the melted liquid from a vibration member provided at the bottom storing the liquid in the tank container. Therefore, forced convection can be reliably generated to promote the thawing of the frozen liquid.
[0026]
According to the seventh aspect, in addition to the effect of the sixth aspect, the pulsation of the heating fluid can be further increased by the Karman vortex generated by the vortex generating means, so that the forced convection of the liquid is further strengthened and frozen. The melting of the liquid can be further promoted.
[0027]
According to the invention of claim 8, in addition to the effect of the invention of claim 6 or 7, the pulsation of the heating fluid discharged from the circulating pump can be further increased by the driving voltage changed by the voltage changing means. The forced convection can be further enhanced to further promote the thawing of the frozen liquid.
[0028]
According to the ninth aspect of the present invention, in addition to the effects of the first to eighth aspects, since the frozen liquid in the suction pipe of the liquid pump can be thawed by the heating element, the liquid pump sucks the ice block. Damage can be prevented.
[0029]
According to the tenth aspect, in addition to the effect of the ninth aspect, when a small amount of ice remains in the melted liquid in the suction pipe or the tank container, a predetermined amount of ice is prevented by the ice block preventing means. Ice blocks larger than the size can be blocked from passing through the suction pipe to prevent the liquid pump from being sucked.
[0030]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0031]
(1st Embodiment)
1 to 4 show a first embodiment of a storage tank for a liquid that can be frozen according to the present invention, FIG. 1 is an overall view showing a basic structure of a fuel cell system using the storage tank of this embodiment, and FIG. FIG. 3 is an enlarged cross-sectional side view of the storage tank, and FIG. 4 is an enlarged cross-sectional view showing the melting state of ice in this embodiment.
[0032]
The freezing liquid stored in the storage tank 10 of the first embodiment is an example in the case of pure water generated in the fuel cell system 100 as shown in FIG.
[0033]
That is, the fuel cell system 100 shown in FIG. 1 includes an FC stack 110 which is a fuel cell main body, and the FC stack 110 takes in a fuel electrode 111 for introducing hydrogen supplied from a compressed hydrogen tank 120 and an outside from the outside. An air electrode 112 for introducing air is provided, and power is generated by chemically reacting hydrogen introduced into the fuel electrode 111 and the air electrode 112 with oxygen in the air using the reverse principle of electrolysis of water. It has become.
[0034]
The fuel cell system 100 according to this embodiment uses pure hydrogen supplied from the compressed hydrogen tank 120 as fuel, and supplies this hydrogen directly to the fuel electrode 111 without using a reformer. It has become.
[0035]
In the FC stack 110, pure water W is generated along with power generation by the reaction between hydrogen and oxygen, and the pure water W is stored in the pure water tank 10 as a storage tank. The pure water W is supplied to a humidifier 130 that humidifies the hydrogen and air introduced into the FC stack 110.
[0036]
Further, the FC stack 110 is provided with a heat exchanger 113 for removing heat generated at the time of power generation, and circulates antifreeze as a cooling medium to a cooling circuit 141 connecting the heat exchanger 13 and the radiator 140. The cooling circuit 141 is connected to the pure water tank 10 to exchange heat.
[0037]
In FIG. 1, a thin solid line α is a flow path of air, a dashed line β is a flow path of hydrogen, a thick broken line γ is a flow path of antifreeze in the cooling circuit 141, and a thick solid line δ is a flow path of pure water W for humidification. Is shown.
[0038]
As shown in FIGS. 2 and 3, the pure water tank 10 includes a tank container 11 for storing pure water W, and a liquid pump for sucking the pure water W stored in the tank container 11 and supplying the pure water W to the humidifier 130. And a pure water pump 20.
[0039]
The tank container 11 is formed as a hermetically sealed structure by a bottom plate 12 serving as a bottom portion, a peripheral side wall 13 and a top plate 14. The pure water pump 20 is installed on the top surface of the top plate 14. The suction pipe 21 is inserted into the pure water W stored in the tank container 11 from the opening 14 a formed in the tank 14.
[0040]
In addition, the top plate 14 of the tank container 11 is provided with a return pipe 30 for introducing pure water W generated at the time of power generation of the FC stack 110, and a breather pipe 31 communicating with the upper part of the tank container 11 is provided. is there.
[0041]
The tank container 11 is provided with a predetermined interval outside the bottom plate 12 and the side wall 13 and is covered with the bottom plate 15 and the back wall 16 to form a double structure. A passage 17 serving as a heating means is formed between the heat sink and the return side wall 16, and the antifreeze in the cooling circuit 141 is circulated as the heating liquid L through the passage 17.
[0042]
As shown in FIG. 2, the heating liquid L is introduced into the passage 17 from an inlet pipe 15 a provided at the center of the return plate 15, and then discharged from an outlet pipe 16 a provided at the upper end of the return wall 16. First, the heating liquid L introduced from the inlet pipe 15a into the passage 17A in a portion corresponding to the bottom plate 12 flows along the bottom plate 12 in the direction perpendicular to the plane of FIG. 2 and from both ends in the direction perpendicular to the plane of FIG. As shown, it flows into the passage 17B1 corresponding to the side wall 13, flows upward in this passage 17B1 and in the direction perpendicular to the plane of FIG. 3, and then flows into the right passage 17B2 in FIG. .
[0043]
Inside the tank container 11 surrounded by the bottom plate 12 and the side walls 13, a plurality of fins 18 arranged in a vertical direction in parallel with the left and right side walls 13 in FIG. 2 penetrates a plurality of tubes 18a together with the side walls 13 on both sides, and communicates with the passages 17B2 and 17B3 on both sides in FIG. 2 through these tubes 18a.
[0044]
Accordingly, the heating liquid L flowing into the right passage 17B2 in FIG. 2 flows into the left passage 17B3 in FIG. 2 through the tube 18a, and then is discharged from the passage 17B3 to the outlet pipe 16a. When the heating liquid L passes through the tube 18a, the heat of the heating liquid L is transmitted to the fins 18.
[0045]
At the center of the bottom plate 12 corresponding to the inlet pipe 15a, an opening 12a having a diameter D sufficiently larger than the diameter of the inlet pipe 15a is formed, and the opening 12a is protruded into the tank container 11. It is closed by a metal bellows tube 40 as a volume change permitting means arranged in a vertical position.
[0046]
Also, openings 13a and 13b having substantially the same diameter as the opening 12a are formed in the center of the left and right side walls 13 shown in FIG. 3, and the metal bellows tube 41 as volume change permitting means is formed in these openings 13a and 13b. , 42 are attached, and when the pure water W in the tank container 11 freezes, the metal bellows tubes 40, 41, 42 contract to allow a change in volume of the pure water W expanded by freezing. I have.
[0047]
A vibrating means 50 for applying vibration to the pure water W is provided at the bottom of the tank container 11. The vibrating means 50 according to the first embodiment includes the vibrating means 50 provided on the bottom surface 12. The bellows tube 40 is used as a vibration member, and when the heating liquid L introduced from the inlet pipe 15a collides with the metal bellows tube 40, the metal bellows tube 40 is vibrated by the pulsation present in the heating liquid L. I have.
[0048]
(Action)
With the above configuration, in the pure water tank 10 of the first embodiment, the bottom wall 12 and the side wall 13 of the tank container 11 are formed in a double structure to form the passage 17, and the heating liquid L is circulated through the passage 17. Therefore, when the pure water W in the storage tank 10 freezes in cold weather or the like, the heat of the heating liquid L is applied to the pure water W frozen from the bottom of the tank container 11 and the surroundings to reduce the melting rate. At the same time, the convection of the pure water W melted by heating from the bottom surface 12 is generated, and the melting of the pure water W frozen around the convection portion can be promoted.
[0049]
Further, in this embodiment, since the heating means is the passage 17 for circulating the heating liquid L, the bottom wall 12 and the side wall 13 of the tank container 11 can be uniformly heated by the heating liquid L. Melting can be accelerated by uniformly applying thermal energy to the parts that come into contact with the metal.
[0050]
Further, since the metal bellows tube 40 vibrating due to the pulsation of the heating liquid L introduced into the passage 17 is provided on the bottom surface 12 of the tank container 11, the partially melted pure water W is forcibly vibrated to freeze surrounding water. Since the melting of the pure water W can be promoted and the vibrating metal bellows tube 40 is provided on the bottom surface 12, the molten pure water W can be vibrated up and down to generate forced convection. Thawing of the frozen pure water W around it can be accelerated.
[0051]
Furthermore, since the metal bellows tube 40 vibrates due to the pulsation of the heating liquid L, a large vibration energy can be added to the melted pure water W, so that forced convection is reliably generated to promote the melting of the frozen pure water W. can do.
[0052]
Further, in this embodiment, since a plurality of fins 18 for transmitting the heat of the heating liquid L are provided inside the tank container 11, the fins 18 can heat the inside of the pure water W frozen. Melting of the pure water W can be promoted by accelerating the melting of the pure water W by providing the fins 18 in the vertical direction, and allowing the molten pure water W to largely convection naturally.
[0053]
That is, in the first embodiment, when the pure water W frozen around the fins 18 is thawed as shown in FIG. 4, vibration is applied to the thawed pure water W from the metal bellows tube 40, and the frozen water is frozen. The melting of the pure water W can be greatly promoted, and the fuel cell system 100 shown in FIG. 1 can promptly secure an amount required to supply the water from the storage tank 10 to the humidifier 130. It is possible to operate the battery system 100 more quickly.
[0054]
Furthermore, in this embodiment, metal bellows tubes 40, 41, and 42 are provided on the bottom surface 12 and the side wall 13 of the tank container 11 to allow a change in the volume inside the tank container 11, so that when the pure water W freezes, Excessive outward pressing force due to volume expansion is suppressed from acting on the bottom surface 12 and the side wall 13, so that the tank container 11 can be prevented from being damaged.
[0055]
(2nd Embodiment)
FIG. 5 shows a second embodiment of the present invention, in which the same components as those in the first embodiment are denoted by the same reference numerals, and a duplicate description will be omitted.
[0056]
FIG. 5 is an enlarged sectional front view of the storage tank. The storage tank 10a according to the second embodiment has a Karman vortex vortex near an inlet for introducing the heating liquid L into the tank container 11, that is, an inlet of the inlet pipe 15a. A resistor 51 is provided as a means.
[0057]
The resistor 51 is formed as a columnar body having a circular cross section, and the length direction of the resistor 51 is arranged at right angles to the direction in which the heating liquid L flows into the passage 17 from the inlet pipe 15a (upward in the figure). When the inflowing heating liquid L collides with the resistor 51, a Karman vortex S is generated on the downstream side.
[0058]
Therefore, in the storage tank 10a of the second embodiment, in addition to the operation and effect of the first embodiment, the pulsation of the heating liquid L can be further increased by the Karman vortex S generated by the resistor 51. Vibration of the metal bellows tube 40 as a vibrating member can be increased to further enhance forced convection of the melted pure water W, and further promote melting of the frozen pure water W.
[0059]
(Third embodiment)
FIG. 6 shows a third embodiment of the present invention, in which the same components as those in the first embodiment are denoted by the same reference numerals, and a duplicate description will be omitted.
[0060]
FIG. 6 is an enlarged sectional front view of the storage tank. The storage tank 10b of the third embodiment is provided with a voltage changing means 61 for changing a driving voltage of a circulation pump 60 for flowing the heating liquid L. Is used as a vibration means.
[0061]
Therefore, in the storage tank 10b of the third embodiment, in addition to the operation and effect of the storage tank 10 of the first embodiment, the heating discharged from the circulation pump 61 by the driving voltage changed by the voltage changing means 61 Since the pulsation of the liquid L can be further increased, the forced convection of the pure water W can be further enhanced to further promote the melting of the frozen pure water W.
[0062]
Of course, the voltage changing means 61 of the third embodiment can be applied not only to the storage tank 10 of the first embodiment but also to the storage tank 10a of the second embodiment.
[0063]
(Fourth embodiment)
FIGS. 7 and 8 show a fourth embodiment of the present invention, in which the same components as those in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0064]
7 is an enlarged cross-sectional front view of the storage tank, and FIG. 8 is an enlarged cross-sectional view taken along line AA in FIG. 7. The storage tank 10c according to the fourth embodiment includes pure water for sucking molten pure water W. Heat transfer fins 70 are provided in the suction pipe 21 of the W pump, and a mesh 80 is provided as ice block preventing means for blocking passage of ice blocks having a predetermined size or more.
[0065]
The heat transfer fins 70 are formed by assembling two band-like fins 71 having a predetermined length H as shown in FIG. 7 in a cross shape as shown in FIG. As a result, heat at the outer periphery of the suction pipe 21 is transmitted to the center of the suction pipe 21 through the heat transfer fins 70, and the pure heat at the center of the suction pipe 21 is Promotes dissolution.
[0066]
As shown in FIG. 7, the mesh 80 is formed in a conical shape that tapers downward in the pure water W suction direction, that is, downwards, and is attached to the suction port 20 a of the pure water pump 20.
[0067]
Therefore, in the storage tank 10c of the fourth embodiment, in addition to the operation and effect of the first embodiment, the frozen liquid in the suction pipe 21 of the pure water pump 20 can be melted by the heat transfer fins 70. Therefore, it is possible to prevent the pure water pump 20 from sucking and breaking the ice blocks.
[0068]
Further, since the mesh 80 is provided in the suction pipe 21, when a small amount of ice blocks remain in the melted pure water W in the suction pipe 21 or the tank container 11, the mesh 80 causes the mesh 80 to have a predetermined size or more. The ice blocks can be blocked from passing through the suction pipe 21 and can be prevented from being sucked by the pure water pump 20.
[0069]
Of course, the heat transfer fins 70 and the mesh 80 according to the fourth embodiment are not limited to the storage tank 10 according to the first embodiment, but may be applied to the storage tanks 10a and 10b according to the second and third embodiments. be able to.
[0070]
By the way, the storage tank for the liquid that can be frozen according to the present invention has been described by taking the first to fourth embodiments as examples. However, the present invention is not limited to this, and various other embodiments may be used without departing from the gist of the present invention. Can be taken.
[Brief description of the drawings]
FIG. 1 is an overall view showing a basic structure of a fuel cell system using a storage tank according to a first embodiment of the present invention.
FIG. 2 is an enlarged sectional front view of the storage tank according to the first embodiment of the present invention.
FIG. 3 is an enlarged sectional side view of the storage tank according to the first embodiment of the present invention.
FIG. 4 is an enlarged sectional view showing a state of melting of ice in the first embodiment of the present invention.
FIG. 5 is an enlarged sectional front view of a storage tank according to a second embodiment of the present invention.
FIG. 6 is an enlarged sectional front view of a storage tank according to a third embodiment of the present invention.
FIG. 7 is an enlarged sectional front view of a storage tank according to a fourth embodiment of the present invention.
FIG. 8 is an enlarged sectional view taken along line AA in FIG. 7;
[Explanation of symbols]
10, 10a, 10b, 10c Pure water tank (storage tank)
11 tank container 12 bottom plate (bottom)
13 Side wall (around)
15 Returning bottom plate 16 Returning side wall 17 Passage (heating means)
18 Fin 20 Pure water pump (liquid pump)
21 Suction pipe 40 Metal bellose pipe (volume change permitting means, vibrating member)
41, 42 Metal bellows tube (volume change permitting means)
50 Exciting means 51 Resistor (vortex generating means)
Reference Signs List 60 circulating pump 61 voltage changing means 70 heat transfer fin (heating element)
80 mesh (ice block prevention means)
W Pure water L Heated liquid

Claims (10)

When the stored liquid is frozen, in a storage tank for a liquid that can be frozen and thawed this frozen liquid,
A storage tank for a liquid that can be frozen, wherein a heating means is provided around at least a bottom portion of the tank container, and a vibrating means for applying vibration to a partially melted liquid is provided. The freezing liquid storage tank according to claim 1, wherein a fin for transmitting heat of the heating means is provided in a vertical direction inside the tank container. The storage tank according to claim 1 or 2, wherein the tank container is provided with a volume change permitting unit that allows a volume change when the liquid is frozen. The storage tank according to claim 1, wherein the vibrating means is provided at a bottom of the tank container. The storage tank for a liquid that can be frozen according to any one of claims 1 to 4, wherein the heating unit is a passage that circulates a heating fluid by forming a double wall structure around at least the bottom of the tank container. . 6. The storage tank according to claim 5, wherein the vibrating means is a vibrating member provided on a bottom portion of the tank container storing the liquid and vibrating by pulsation of the introduced heating fluid. The storage tank according to claim 6, wherein the vibrating means is a Karman vortex vortex generating means provided near an inlet for introducing the heating fluid into the tank container. 8. The storage tank according to claim 6, wherein the vibrating means is a voltage changing means for changing a driving voltage of a circulation pump for flowing the heating fluid. The freezing liquid storage tank according to any one of claims 1 to 8, wherein a heating element is provided in a suction pipe of the liquid pump that sucks the melted liquid. 10. The freezing liquid storage tank according to claim 9, wherein an ice block preventing means for blocking passage of ice blocks having a predetermined size or more is provided in the suction pipe.

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