JPH0486469A - Heat discharging device - Google Patents

Abstract

PURPOSE:To improve the reliability of heat discharging device and reduce the refrigerant consumption by a method wherein a temperature difference between the inlet port and the outlet port of secondary refrigerant is increased and hydrogen is employed as the secondary refrigerant while at least one of heat generating sources is a fuel battery, in the heat discharging device of a space shuttle. CONSTITUTION:Secondary refrigerant (c) or hydrogen is supplied from a hydrogen tank 47 into a hydrogen heat exchanger 45 at the temperature of 4k-50k at the inlet port 51 under the condition of super-critical flow or gas. The temperature difference of the secondary refrigerant (c) between the outlet port 55 and the inlet port 51 of the hydrogen heat exchanger 45 is specified as 200k-400k. According to this method, the removing amount of heat per unit weight of the secondary refrigerant (c) is increased whereby the consumption of the secondary refrigerant can be reduced. The consumption of the secondary refrigerant (c) can be reduced in the case of hydrogen than water or ammonia. Hydrogen, necessary for a fuel battery, in the hydrogen discharged out of the hydrogen heat exchanger 45 is supplied to the fuel battery 17 through a hydrogen transporting pipe 63 while the balance of the hydrogen is discharged into space or atmosphere through a hydrogen dischaging pipe 61.

Description

[Detailed description of the invention] [Object of the invention] (Industrial application field) The present invention relates to a heat exhaust device for discharging heat to the outside,
In particular, the present invention relates to a heat exhaust device suitable for discharging heat generated inside a spacecraft into outer space or the atmosphere.

(Prior Art) For example, heat generated inside a spacecraft is often released into space by radiant heat transfer from a heat sink provided on the outside of the spacecraft.

Furthermore, when a spacecraft becomes large or there are multiple heat sources inside the spacecraft, a heat exhaust device having the configuration shown below is used.

A pump that pumps and circulates the primary refrigerant within the transport pipe is placed in the middle of the transport pipe formed in a loop shape and filled with the primary refrigerant. A first heat exchange section that exchanges heat with the primary refrigerant, and a heat radiation heat exchange section that releases heat of the primary refrigerant are arranged. Further, a third heat exchange section is disposed downstream of the first heat exchange section in the direction in which the primary refrigerant is pumped, for exchanging heat with the primary refrigerant and discharging the heat from the heat generation source discharged to the primary refrigerant to the secondary refrigerant. A secondary refrigerant supply/discharge means is disposed for supplying the secondary refrigerant to the third heat exchange section and for discharging the secondary refrigerant after heat exchange with the primary refrigerant.

In this case, in the second heat exchange section, the primary refrigerant and the heat sink exchange heat, heat is transferred from the heat exhaust device to the heat sink, and is emitted from the heat sink into space.

By the way, in a spacecraft, which is a type of space vehicle such as the U.S. Space Shuttle, heat generated inside the spacecraft and aerodynamic heating by the atmosphere are generated during the ascent by the rocket and the descent by the spacecraft itself. It is necessary to release the penetrating heat into space or the atmosphere.

However, since spacecraft travel at high speed in space or in the atmosphere, the heat sink is stored inside and cannot be used when ascending or descending.

Therefore, the heat exhaust system used in the spacecraft of the U.S. Space Yatoru consists of a heat exchanger for heat radiation, which exchanges heat with the heat sink used when the spacecraft is moving in orbit, and a secondary heat exchanger. It is equipped with a heat exchanger with a refrigerant as a heat radiation exchange section. In a heat exchanger with a secondary refrigerant, the secondary refrigerant to which heat has been transferred from the primary refrigerant is discharged into space or the atmosphere.

Normally, secondary refrigerant is loaded onto a spacecraft when it is launched, so in order to reduce the onboard weight, a refrigerant that removes a large amount of heat per unit mass is used, which reduces the amount of secondary refrigerant consumed. desirable.

FIG. 6 shows a conventional heat exhaust device 101 equipped with a heat radiation exchange section using the above-mentioned secondary refrigerant. This heat exhaust device 10
1 is the configuration of the heat exhaust device and the track used in the U.S. Space Shuttle. As shown in FIG. 6, the primary refrigerant transport pipe 3 connects the pump 5, the cold plate 7, the fuel cell cooler 9, the radiator to the rudder 11, and the water evaporator 13.
, an ammonia boiler 15 are connected.

The primary refrigerant a flows through the primary refrigerant transport pipe 3 by the pump 5, which includes a cold plate 7, a fuel cell cooler 9, a radiator header 11, a water evaporator 13, and an ammonia boiler 15.
The refrigerant is returned to the pump 5 via the following steps, and is sent out again to the primary refrigerant transport pipe 3, where it is circulated under pressure within the transport pipe.

The cold plate 7 is a heat exchange section with a heat generation source such as an electronic device, and the fuel cell cooler 9 is a heat exchange section with a fuel cell 17 as a heat generation source. Here, the fuel cell refrigerant which directly cools the fuel cell 17 is cooled by a primary refrigerant a such as Freon.

Note that the fuel cell 17 and the fuel cell cooler 9 are connected by a fuel cell refrigerant transport pipe 19.

The primary coolant a absorbs heat in the cold plate 7 and the fuel cell cooler 9, and its temperature rises to about 70°C. The radiator header 11 is connected to the heat sink 21 by a heat pipe 23, and is a heat exchange section for heat radiation that exchanges heat with the heat sink 21. The water evaporator 13 and the ammonia boiler 15 use the primary refrigerant a
and secondary refrigerant C, both of which are heat exchange parts for heat radiation.

The secondary refrigerant C of the water evaporator 13 is water, and the secondary refrigerant C of the ammonia boiler 15 is ammonia. Secondary refrigerant C
Water is stored in a water tank 25, and ammonia as a secondary refrigerant C is stored in an ammonia tank 27. These secondary refrigerants C, water and ammonia, are supplied to the water evaporator 1 through a water supply pipe 29 and an ammonia supply pipe 31, respectively.
3 and ammonia boiler 15, respectively.

The secondary refrigerant C, which has removed heat from the primary refrigerant a by the water evaporator 13 and the ammonia boiler 15, evaporates and becomes a gas. , or released into the atmosphere.

In addition, in order to operate the fuel cell 17, a fuel cell hydrogen tank 37 and three fuel cell oxygen tanks are provided, and hydrogen and oxygen are supplied to the fuel cell hydrogen supply pipe 41, respectively.
and is supplied to the fuel cell 17 through a fuel cell oxygen supply pipe 43.

In addition, the conventional heat exhaust device 101 has a cold play 1.
In order to keep the temperature of the primary refrigerant a at the outlet of the refrigerant 7 below 40°C, the inlet temperature of the pump 5 for the primary refrigerant a is usually set to about 5°C, and the evaporation temperature of the secondary refrigerant C is also usually below 5°C. .

By the way, water has the maximum latent heat of vaporization, but water evaporator] 3
In order to keep the evaporation temperature within the tank below 5°C, it is necessary to control the saturation pressure of water to below 0.01 atm, and the outlet pressure of water vapor to below 0.01 atm. Therefore, the outside pressure is 0.
At low altitudes or on the ground, where the temperature exceeds 0.01 atmospheres, it is impossible to exhaust steam to the outside of the spacecraft.

Therefore, the heat exhaust device 01 with the above-mentioned conventional configuration uses ammonia as a secondary refrigerant, which has the second largest latent heat of steam after water, and whose saturation temperature at 1 atm is 133°C, which is much lower than the evaporation temperature of 5°C. It is equipped with an ammonia boiler 15 for use. As a result, at altitudes where it is difficult to exhaust water vapor to the outside of the spacecraft, a switching operation is performed in which the supply of water to the water evaporator 13 is stopped and the supply of ammonia to the ammonia boiler 15 is started. ing.

In this way, in the conventional heat exhaust device 101, the water evaporator 13
It is necessary to prepare two types of heat exchangers: a water evaporator 13 and an ammonia boiler 15, and to switch between the water evaporator 13 and the ammonia boiler 15 during the descent of the spacecraft.
Operation control becomes complicated. Furthermore, since there is a possibility that the switching device may fail, there is a problem of lowering reliability.

In addition, the ammonia boiler] 5 can be used during all periods of rise and fall, or the latent heat of vaporization of ammonia is 1/2 of the latent heat of vaporization of water. When heat is removed, the consumption amount of the secondary refrigerant C increases significantly compared to the case of this conventional example. Therefore, the weight loaded onto the spacecraft becomes heavier.

On the other hand, in the water evaporator 13 and the ammonia boiler 15, the secondary refrigerant C changes from the liquid phase to the gas phase, but when the gas phase and liquid phase are mixed, it is affected by the magnitude of gravity and the direction of gravity. However, there are limits to verifying its behavior on the ground. For this reason, a problem arises in that it is not possible to fully grasp the performance when used inside a spacecraft.

Additionally, in spacecraft, heat is emitted from mechanical systems in addition to electronic equipment. Heat from this mechanical system is exhausted to the oil. For this reason, it is necessary to cool this oil.

As a heat exchanger for oil cooling, there are two types of heat exchangers: one that directly exchanges heat between the oil and the secondary refrigerant, and one that exchanges heat via Freon (the Freon is cooled by the secondary refrigerant, and the Freon is used to cool the oil). .

The oil inlet temperature is 120°, and water can be used as a secondary refrigerant to cool everything from space to the ground.

On the other hand, when exchanging heat between Freon and a secondary refrigerant, using Freon as the primary refrigerant is a configuration that leads to weight reduction, but the maximum heat load of the oil cooling heat exchanger is usually much larger than the load.

Therefore, in order to suppress the maximum temperature of Freon to 70° or less without increasing the Freon flow rate, the Freon temperature at the inlet of the oil cooling heat exchanger must be set at -30° to -100°.
It must be lowered to ℃. At this temperature level, there is a high possibility that Freon will freeze on the inner surface of the Freon channel.

Therefore, in conventional examples such as the Space Shuttle, a water/oil heat exchanger using water as the secondary refrigerant and a freon/oil heat exchanger have been proposed.
Two types of heat exchangers are prepared: an oil heat exchanger. When cooling oil, a water/oil heat exchanger is used, and when the oil temperature is low in orbit, a freon/oil heat exchanger is used. Heat is maintained using an exchanger.

(Problem to be solved by the invention) In this way, in the conventional heat exhaust device, two types of heat exchangers are prepared for the primary refrigerant and the secondary refrigerant, and these are used during the descent, that is, depending on the environment in which the heat is to be exhausted. The need to switch heat exchangers complicates operation control and reduces reliability.

In addition, the secondary refrigerant changes from the liquid phase to the gas phase in the heat exchanger, and the heat exchange performance is affected by the magnitude and direction of gravity, so it is difficult to fully understand the performance when used inside the spacecraft. There is also the problem that there is no such thing.

In consideration of the above facts, the present invention provides a heat exchanger between a primary refrigerant and a secondary refrigerant with high reliability, a large amount of heat removal per unit weight of the secondary refrigerant in the heat exchanger, and a sufficient performance understanding. The purpose is to provide a heat exhaust device that is capable of

[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above object, the invention of claim (1) provides that the inlet temperature of the heat exchange section of the secondary refrigerant is between 4K and 50K, and the secondary refrigerant The difference between the refrigerant inlet temperature and the heat exchanger outlet temperature is 2
It is characterized by being more than 0.00K and less than 400K.

Further, the invention according to claim (2) is characterized in that the secondary refrigerant is hydrogen.

Furthermore, the invention of claim (3) is characterized in that at least one of the heat generation sources is a fuel cell, and the outlet of the secondary refrigerant of the heat exchanger is connected to the hydrogen supply port of the fuel cell or by piping. There is.

(Function) According to the invention of claim (1) having the above configuration, since the temperature difference between the inlet and the outlet of the secondary refrigerant in the heat exchange section between the secondary refrigerant and the secondary refrigerant is large, the temperature difference per unit mass of the secondary refrigerant is The amount of heat that can be removed from the primary refrigerant using sensible heat increases, making it possible to secure the required amount of exhaust heat without evaporating the secondary refrigerant.

Therefore, the liquid phase and gas phase of the secondary refrigerant do not coexist, and the performance of the heat exchanger is not affected by the magnitude of gravity or the direction of gravity. As a result, for example, the performance inside the spacecraft is in line with the performance on the ground, and it is possible to fully understand the performance.

In addition, the pressure of the secondary refrigerant in the heat exchanger can be set high regardless of the saturation pressure, so if one type of refrigerant, for example hydrogen of the invention of claim (2), is used as a refrigerant, it will continue regardless of altitude. It can be used as

Furthermore, in the invention of claim (3), for example, hydrogen for a fuel cell mounted on a spacecraft is used as a secondary refrigerant.

(Example) Next, a first example and a second example of the present invention will be described with reference to FIGS. 1 to 3. Components that are the same as those of the conventional example shown in FIG. 4 are given the same reference numerals in the figure, and their explanations are omitted.

First Embodiment The difference between the heat exhaust device 1 of the first embodiment and the conventional heat exhaust device 101 shown in FIG. A hydrogen heat exchanger 45 that serves as refrigerant C is connected to a hydrogen tank 47 that stores secondary refrigerant C and a hydrogen supply pipe 49, and hydrogen that is secondary refrigerant C is supplied from the hydrogen tank 47 to the hydrogen heat exchanger 45. It is to be done.

Further, the temperature of the inlet 51 of the secondary refrigerant C to the hydrogen heat exchanger 45 is set to 14K to 50K, preferably 35K, and the inlet state is a supercritical flow or a gas state.

If the temperature at the inlet 53 of the primary refrigerant a to the hydrogen heat exchanger 45 is approximately 70°C, the temperature at the outlet 55 of hydrogen, which is the secondary refrigerant C, from the hydrogen heat exchanger 45 is approximately 0 to 50°C. There is. Also, the outlet 5 of the secondary refrigerant C in the hydrogen heat exchanger 45
5 and the inlet 51 is between 200 and 400, preferably between 250 and 300.

Five hydrogen outlet pipes connected to the outlet 55 of the secondary refrigerant C of the hydrogen heat exchanger 45 are branched into a hydrogen exhaust pipe 61 and a hydrogen transport pipe 63. The hydrogen transport pipe 63 is connected to a hydrogen supply port 65 of the fuel cell 17.

Of the hydrogen that is the secondary refrigerant C discharged from the hydrogen heat exchanger 45, the amount necessary for the fuel cell is supplied to the fuel cell 17 through the hydrogen transport pipe 63, and the remaining hydrogen is sent to outer space or the atmosphere through the hydrogen exhaust pipe 61. released to.

Next, the operation of this embodiment will be explained.

The primary refrigerant a, which is pumped and circulated through the primary refrigerant transport pipe 3 by the pump 5, is heated by the cold plate 7, which has been heat-exchanged with a heat source such as an electronic device, and then the heat generated by the fuel cell 7 or the fuel The heat generated by the replaced cooler 9 is absorbed by the battery refrigerant. As a result, the primary refrigerant a changes from about 5°C to about 70°C.
The temperature rises to ℃.

When the heat sink 21 is usable on the orbit, the heat of the primary coolant a whose temperature has increased is released from the heat sink 21 via the radiator header 11, and the heat sink 21 when ascending or descending. If it is not possible to use it, it passes through Radar 1] to the radiator without any heat transfer.

The primary refrigerant a that has passed through the radiator 1] is sent into the hydrogen heat exchanger 45. Hydrogen, which is a secondary refrigerant C, is supplied into the hydrogen heat exchanger 45, and this hydrogen and the primary refrigerant a exchange heat, absorbing the heat of the primary refrigerant, and exhausting it from the hydrogen heat exchanger 45. be done.

When the inlet state of hydrogen, which is secondary refrigerant C, is 50°C gas and the outlet state is 0°C gas, the amount of heat removed per unit mass, that is, the difference between enthalpy at the inlet and enthalpy at the outlet, is approximately 3800 KJ. /Kg. In addition, the inlet state of hydrogen, which is the secondary refrigerant C, is a supercritical flow of 35, and the outlet state is 2.
When the temperature of the gas is 7°C, the amount of heat removed per unit mass is approximately 4200 KJ/kg.

On the other hand, when water is used as a secondary refrigerant as in the conventional heat exhaust device 101 shown in FIG. 4, the latent heat of vaporization of water at 3°C is 2
500KJ/kg, and when ammonia is used as a secondary refrigerant, the latent heat of vaporization of ammonia at 0℃ is 1260KJ/kg.
kg.

Therefore, according to the heat exhaust device 1 according to the present embodiment, the amount of heat removed per unit mass of the secondary refrigerant C in the heat exchanger between the primary refrigerant a and the secondary refrigerant C is It is larger than the amount of heat removed per unit mass of refrigerant,
It is possible to reduce the consumption of secondary refrigerant.

Next, Table I shows a comparison of the consumption amount of the secondary refrigerant C when the heat exhaust device 1 of this embodiment is applied to a spacecraft (not shown). In Table 1, the spacecraft is located outside the atmosphere, at high altitude, and at low altitude, and the time at these positions, the amount of exhaust heat required, and the media type and media consumption of the present invention and the conventional example are respectively It is shown.

Table I As shown in Table 1, if the spacecraft is located outside the atmosphere for one hour, and the exhaust heat requirement is 8 kW, if the medium is water, the consumption is 11.5 kg. When the medium is hydrogen, the consumption amount is 8.9 kg.

In addition, if the spacecraft is located at a bulk altitude for 0.5 hours and the exhaust heat requirement is 1 lkv, if the medium is water, the consumption will be 7.9 kg, whereas if the medium is hydrogen, the consumption will be 7.9 kg. The consumption amount is 4.7 kg.

Furthermore, if the spacecraft is located at a low altitude for 0.4 hours, and the exhaust heat requirement is 18 kW, if the medium is ammonia, the consumption will be 20.8 kg, but if the medium is hydrogen, the consumption will be 20.8 kg. The consumption amount is 6.2 kg.

Therefore, when hydrogen is used as the medium, the consumption amount may be small.

Further, since the inlet state of hydrogen, which is the secondary refrigerant C, is a gas or supercritical flow, and the outlet state is a gas, the secondary refrigerant C is in a gas-liquid two-phase flow state inside the hydrogen heat exchanger 45. It is not affected by the magnitude of gravity or the direction of gravity.

Therefore, the performance of the hydrogen heat exchanger 45 in the spacecraft is as follows:
Performance on the ground and on the road, resulting in high reliability in performance.

Further, the outlet state of hydrogen, which is the secondary refrigerant C, is a gas,
Since the outlet temperature is much higher than the critical temperature, the outlet pressure can be determined independently of the outlet temperature.

Therefore, the hydrogen heat exchanger 45 can be used continuously from orbit to the ground, and there is no need to switch heat exchangers as in the conventional case, so reliability can be improved in this respect as well.

Second example Next, a second embodiment will be explained using FIG. 2.

In the heat exhaust device 2 of the second embodiment, hydrogen is used as the secondary refrigerant C in the first embodiment described above, but in the second embodiment, helium is used as the secondary refrigerant C.

As shown in FIG. 2, the hydrogen heat exchanger 45 of the first embodiment
is replaced by a helium heat exchanger 67, the hydrogen tank 47 is replaced by a helium tank 69, and the helium heat exchanger 67 is connected to the helium tank 69 by a helium supply pipe 71,
A helium exhaust pipe 73 is connected to the secondary refrigerant outlet side of the helium heat exchanger 67 . Therefore, hydrogen for the fuel cell is supplied from a dedicated hydrogen tank 37 for the fuel cell through the hydrogen supply pipe for the fuel cell, as in the conventional case.

According to the second embodiment, the helium heat exchanger 67 can be used continuously regardless of the altitude of the spacecraft on which it is mounted. Furthermore, by setting the inlet state of helium, which is a secondary refrigerant, to supercritical flow or gas, helium does not become a gas-liquid mixed state in the helium heat exchanger 67, so it is not affected by the magnitude of gravity or the direction of gravity. I have never received one.

Therefore, since the helium heat exchanger is not affected by gravity and its performance can be fully grasped, its reliability can be improved compared to the heat exhaust device 101.

Also, the specific heat of helium is smaller than that of hydrogen, so if the inlet state is a supercritical flow of lOk and the outlet state is a gas of 27°C, the amount of heat removed per unit mass of helium is L53.
It is 0 kJ/kg, which is larger than the latent heat of vaporization of ammonia but smaller than the latent heat of vaporization of water.

Therefore, the amount of refrigerant consumed may be greater than that of the conventional heat exhaust device 101.

Third Embodiment Next, a third embodiment will be explained with reference to FIG. The heat exhaust device 4 of the third embodiment includes a water evaporator 13 and a helium heat exchanger 67 as heat exchangers between the primary refrigerant a and the secondary refrigerant C.
A water evaporator is used at high altitudes, and a helium heat exchanger 67 is used at low altitudes.

In this third embodiment, two types of heat exchangers are switched during descent, so there is little contribution to improving reliability.

However, when used at low altitudes or on the ground, the helium heat exchanger 67 is extremely safe against emitted refrigerants compared to ammonia in conventional heat exhaust devices, so it is less safe for workers and local residents at the landing site. This greatly contributes to reducing environmental pollution.

Furthermore, in the third embodiment, since the conventional ammonia boiler is replaced with a helium heat exchanger, the amount of media consumed can also be reduced.

In each of the above embodiments, helium and hydrogen are used as the secondary refrigerant, but the secondary refrigerant is not limited to this, and any material having a low critical temperature and a large specific heat may be used.

Further, the present invention is not limited to the heat exhaust devices of the above embodiments, but can be applied to other heat exhaust devices.

Further, in each of the above embodiments, an example of a heat exhaust device installed on a spacecraft is described, but the heat exhaust device of the present invention is not limited to this, but can also be applied to a heat exhaust device installed on a vehicle other than a spacecraft. I can do it.

Fourth Embodiment Next, a fourth embodiment will be explained with reference to FIGS. 4 and 5. This fourth embodiment is an example in which a hydrogen/oil heat exchanger 75 for cooling oil is disposed in the heat exhaust device 1 of the first embodiment, and hydrogen is used for cooling the oil.

As described in the first embodiment, the amount of heat removed per unit mass when hydrogen is used as the secondary refrigerant is greater than when using water, so the consumption amount of the medium can be reduced.

However, the lower limit of the oil temperature is room temperature, and the temperature of the wall surface of the oil flow path must be kept at or above room temperature. Considering that hydrogen is at an extremely low temperature, it is not easy to design a heat exhaust device that satisfies this condition.

Therefore, first, two measures taken to solve the conventional problems in using hydrogen for oil cooling will be explained, and then a heat exhaust device to which these measures are applied will be explained.

The first measure is that during the operation period of the oil cooling heat exchanger,
The hydrogen heat exchanger for the loop is also in operation, and approximately 300% of hydrogen is discharged from the hydrogen heat exchanger. Therefore, this room temperature hydrogen is mixed with extremely low temperature hydrogen supplied from the hydrogen tank to the oil cooling hydrogen heat exchanger to raise the hydrogen temperature. In this case the hydrogen temperature will be between 100 and 150°C, greatly reducing the possibility of Freon freezing.

Moreover, as a second measure, hydrogen is divided into a low temperature range and a high temperature range, and in the low temperature range (100 to 250 K), heat is exchanged with Freon, and in the high temperature range (200 to 350 K), the oil is directly cooled. With this configuration, it is possible to prevent the oil temperature (wall surface temperature) from dropping significantly beyond room temperature, and the hydrogen outlet temperature can be brought to a value close to the oil temperature (~120℃), so the amount of heat removed from hydrogen can be reduced. will also increase.

FIG. 4 shows an oil cooling hydrogen heat exchanger incorporating the above measures and an applied heat exhaust device, and FIG. 5 shows the configuration of the oil cooling hydrogen heat exchanger.

As shown in FIG. 4, in the heat exhaust device of the fourth embodiment, a hydrogen/oil heat exchanger 75 is disposed in the middle of the primary refrigerant transport pipe. This hydrogen/oil heat exchanger 75 is connected to the hydrogen tank 47 through a hydrogen supply pipe 77, and hydrogen is supplied thereto. A hydrogen transport pipe 76 branched from the hydrogen outlet pipe 59 of the hydrogen heat exchanger 45 is connected to the hydrogen supply pipe 77 .

Therefore, all of the hydrogen discharged from the hydrogen heat exchanger 45 except hydrogen e, which is sent to the fuel cell 17, is sent to the hydrogen/oil heat exchanger 75, and is then newly supplied from the hydrogen tank to the hydrogen supply pipe 77. It is mixed with hydrogen and used as a secondary refrigerant in hydrogen/oil heat exchangers.

Note that the used hydrogen is discharged from the hydrogen exhaust pipe 61.

Further, the hydrogen/oil heat exchanger 75 is communicated with an oil tank 81 through an oil supply pipe 79, and oil is supplied to the hydrogen/oil exchanger 75.

As shown in FIG. 5, the hydrogen/oil heat exchanger 75 is composed of a hydrogen/freon heat exchanger 83, a hydrogen/oil heat exchanger 85, and a freon oil heat exchanger 87.

The 120°C oil from which heat from the mechanical system has been discharged is sent to the oil/Freon heat exchanger 87, where it is brought to 0°C and converted into oil/freon heat exchanger 87.
Heat is exchanged with the Freon sent to the Freon heat exchanger 87, and the mechanical heat that is discharged to the oil is discharged to the Freon.

Hydrogen 110 supplied to the hydrogen/Freon heat exchanger 83 through the hydrogen supply pipe 77 exchanges heat with Freon and becomes 2
10 and is sent to the hydrogen/oil heat exchanger 85.

In the hydrogen/oil heat exchanger 85, hydrogen exchanges heat with oil at 116°C and becomes 350K.

In this embodiment with the above configuration, hydrogen at a low temperature (100 to 150 K) exchanges heat with Freon, and the temperature rises to 200 to 250°C. At this time, the freon outlet temperature is restricted by anti-freezing conditions, but since the hydrogen inlet temperature is between 100 and 150, the freon outlet temperature can be lowered to about 0°C.

The cooled Freon exchanges heat with the oil and becomes 7 again.
Return to 0℃. The oil cooled by the oil/Freon heat exchanger 87 enters the hydrogen/oil heat exchanger 85 and is further cooled by hydrogen.

For each temperature shown in Fig. 5, the heat load of the thermal control loop is 11kw, and the heat load of the oil cooling heat exchanger is 28
k w , Freon entrance and exit temperatures are 70℃ and 4, respectively.
This is the estimated temperature at each inlet and outlet of each heat exchanger at ℃ (rated operation). As a result of the above studies, we have found a way to design an oil cooling heat exchanger using a hydrogen medium.

It is highly possible that the oil/Freon heat exchange section can also be used as a heat exchanger for keeping oil warm on orbit.

Furthermore, in each of the above embodiments, hydrogen after being used as a secondary refrigerant is discharged into space or the atmosphere unless it is used in a fuel cell. It can also be used for For example, in the case of a re-entering aircraft, it can be used to cool the wall surface during re-entry.

[Effect of the invention] As explained above, in the inventions of claims (1) to (3), one type of heat exchanger is used as a heat exchanger for primary refrigerant and secondary refrigerant regardless of altitude. Also, since the secondary refrigerant does not become a gas-liquid mixture in the heat exchanger, the reliability of the heat exhaust device can be improved. For example, when hydrogen is used as the secondary refrigerant, An excellent effect can be obtained in that refrigerant consumption can be significantly reduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing a first embodiment of a heat exhaust device according to the present invention, FIG. 2 is a schematic configuration diagram showing a heat exhaust device of a second embodiment, and FIG. 3 is a schematic configuration diagram showing a heat exhaust device of a third embodiment. A schematic configuration diagram showing a thermal device,
Fig. 4 is a schematic configuration diagram showing the heat exhaust device of the fourth embodiment;
The figure is a schematic block diagram showing a hydrogen/oil heat exchanger, and FIG. 6 is a schematic block diagram showing a conventional heat exhaust device. 1.2.4... Heat exhaust device 3... Primary refrigerant transport pipe 5.
...Pump 7...Cold plate 1
7...Fuel cell 45...-Hydrogen heat exchanger 2
C... Heat sink 63... Hydrogen transport pipe 67
... Helium heat exchanger 69 ... Helium tank 75
...Hydrogen/oil heat exchanger

Claims (3)

[Claims] (1) A transport pipe formed in a loop shape and having a primary refrigerant sealed therein; A pump disposed in the middle of this transport pipe to pump and circulate the primary refrigerant within the transport pipe; and a pump that pumps and circulates the primary refrigerant. a first heat exchange section that is disposed downstream in the direction and exchanges heat between the heat generation source and the primary refrigerant; and a first heat exchange section that is disposed downstream in the primary refrigerant pumping circulation direction of the first heat exchange section and exchanges heat of the primary refrigerant. a second heat exchange section disposed downstream in the primary refrigerant pumping circulation direction of the first heat exchange section, and exchanging heat with the primary refrigerant and discharging heat from the heat source to the primary refrigerant. a third heat exchange section that discharges the secondary refrigerant to the secondary refrigerant; and a secondary refrigerant supply/discharge that supplies the secondary refrigerant to the third heat exchange section and discharges the secondary refrigerant after being heat exchanged with the primary refrigerant. A heat exhaust device comprising: an inlet temperature of the third heat exchange section of the secondary refrigerant of 4K or more and 50K or less; A heat exhaust device characterized in that the difference between the temperature and the outlet temperature is 200K or more and 400K or less. (2) The heat exhaust device according to claim (1), wherein the secondary refrigerant is hydrogen. (3) At least one of the heat generation sources is a fuel cell, and the outlet of the secondary refrigerant of the third heat exchanger and the hydrogen supply port of the fuel cell are connected by piping. The heat exhaust device according to claim (1) or claim (2).