JPH09264681A - Loop heat pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To operate a loop heat pipe irrespective of presence/absence of the gravity, and the size of the heat flux by fitting a partition to a liquid pipe in an evaporator. SOLUTION: Partitions 18 fitted in the radial direction to a liquid pipe 14 made of the material whose thermal conductivity is equivalent to or less than that of a wick 4, e.g. ceramic, titanium, and stainless steel, deprives the heat of the liquid 13 in a liquid annular pipe 15, the liquid 13 in the annular liquid pipe 15 can be super-cooled. No boiling is achieved from a surface on the liquid annular tube 15 side of the wick 4, and the vapor which is the evaporated working fluid covers no surface of the wick 4 even in the space under the weightless environment, and a loop heat pipe is normally operated even when the heat flux is large, and the heat transfer capacity is not deteriorated. When a recessed part is provided in a part of a vapor flow passage 7 of the wick 4 as soon as the partition 18 is fitted to the liquid pipe 14, the pressure loss between a joined part from the wick 4 to an evaporator vessel 5 and the vapor flow passage 7, and at the vapor flow passage 7 becomes small.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a loop heat pipe used as a heat transport device for space, industrial use and household use.

[0002]

2. Description of the Related Art FIG. 10 is a sectional view of a conventional loop heat pipe. FIG. 11 is a view showing a cross section of the evaporator of FIG. In the figure, 1 is an evaporator composed of a wick, an evaporator container, a vapor flow path, a liquid pipe, a liquid ring, an upper reservoir and a lower reservoir, 2 is a condenser ring, and a condenser composed of a condenser container, 3 is Arrows showing the flow of applied heat, 4 is a wick, 5 is an evaporator container, 6 is a vapor of a working fluid that has been vaporized, 7 is a vapor flow path, 8 is a vapor pipe, and 9 is a flow of vapor of a working fluid. An arrow, 10 is a condensing ring, 11 is an arrow indicating the flow of heat flowing out from the loop heat pipe, 12 is a condenser container, 13 is a liquid of a condensed working fluid, 14 is a liquid pipe, 15 is a liquid ring, and 16 is an upper part. A reservoir, 17 is a lower reservoir.

The operating principle of the conventional loop heat pipe configured as described above will be described. The heat applied to the evaporator 1 indicated by the arrow 3 indicating the heat flow is transmitted to the evaporator container 5, and is transmitted to the working fluid liquid 13 at the joint between the wick 4 and the evaporator container 5, so that the working fluid is Evaporate. The working fluid vapor 6 flows into the condensing ring 10 through the wick 4, the vapor flow path 7, and the vapor pipe 8. The vapor 6 that has flowed into the condensing ring 10 is condensed by transferring heat to the condenser container 12.
Becomes The condensed liquid 13 passes through the liquid pipe 14 and returns to the evaporator 1. The liquid 13 returned to the evaporator 1 is accumulated in the liquid ring 15, the upper reservoir 16 and the lower reservoir 17. Liquid 13 is liquid ring 1
5 is carried to the joint between the wick 4 and the evaporator container 5 by the capillary force of the wick 4.

Heat is transported from the evaporator 1 to the condenser 2 by repeating the above cycle.

[0005]

In the conventional loop heat pipe as described above, when the heat flux becomes large and the heat cannot be taken away only by the amount of evaporation from the vicinity of the contact surface between the evaporator container 5 and the wick 4, Boiling also occurs from the surface of the wick 4 on the liquid ring 15 side. On the ground, the vapor moves to the upper reservoir 16 or the lower reservoir 17 due to the influence of gravity, but when the loop heat pipe is used for an artificial satellite, the vapor 6 which is the working fluid evaporated due to the zero gravity environment in space is wicked. If the surface of the liquid is covered, the liquid 13 cannot flow into the wick, and there is a problem that it does not operate.

The vapor 6 evaporated at the contact portion between the wick 4 and the evaporator container 5 flows in the wick 4 in the circumferential direction and is transported to the vapor flow path 7. The wick thickness is determined by the structural strength, the thermal conductance in the circumferential direction and the radial direction, but there is a problem that the heat transfer ability is reduced when the pressure loss is large and the heat flux is large because the capillary radius is small.

Further, the liquid 13 flows from the liquid ring 15 to the wick 4
Although it is transported to the contact portion between the wick 4 and the evaporator tube wall 5 through the above, there is a problem that the pressure loss is large due to the small capillary radius as described above, and the heat transport capacity decreases when the heat flux becomes large.

The present invention has been made to solve the above problems, and an object thereof is to obtain a loop heat pipe that operates regardless of the presence or absence of gravity and the magnitude of heat flux.

[0009]

The loop heat pipe of the present invention has a partition wall provided on the liquid ring in the evaporator.

Further, the loop heat pipe of the present invention is
The wick is provided with a concave portion in the vapor flow path portion.

The loop heat pipe of the present invention has a recess provided on the liquid ring side of the wick and adjacent to the joint with the evaporator container.

Further, the loop heat pipe of the present invention is
A partition wall is provided in the liquid pipe, and a recess is provided in the vapor flow path portion of the wick.

In the loop heat pipe of the present invention, a partition wall is provided on the liquid pipe, and a recess is provided on the liquid ring side of the wick and adjacent to the joint with the evaporator container.

Further, the loop heat pipe of the present invention is
A recess is provided in each of the vapor flow path portion of the wick and the liquid ring side of the wick and adjacent to the evaporator container and the joint portion.

In the loop heat pipe of the present invention, a partition wall is provided in the liquid pipe, and at the same time, a concave portion is provided in each of the vapor flow passage portion of the wick and the liquid ring side of the wick and adjacent to the joint portion with the evaporator container. It is a thing.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1. 1 is a view showing a cross section of a loop heat pipe showing a first embodiment of the present invention. 2 and 3
[Fig. 3] is a view showing a cross section of the evaporator according to the first embodiment. 1
Nos. 17 to 17 are the same as those of the conventional loop heat pipe.
Reference numeral 18 is a partition wall attached to the liquid pipe 14.

The loop heat pipe shown in FIGS. 1 and 2 is radially attached to a liquid pipe 14 made of a material having a thermal conductivity equal to or lower than that of the wick 4, for example, ceramic, titanium, stainless steel or the like. Since the partition wall 18 removes heat from the liquid 13 in the liquid ring 15, the liquid 13 in the liquid ring 15 can be supercooled. This makes wick 4
No boiling occurs from the surface of the liquid ring 15 side of the wick 4 and the vaporized working fluid 6 does not cover the surface of the wick 4 even in the universe under a zero-gravity environment, and operates normally even if the heat flux is large, Heat transport capacity does not decrease. It goes without saying that the intended purpose can be achieved whether the partition wall 18 is integrated with the liquid pipe 14 or not.

FIG. 3 shows a partition wall 18 provided on the liquid pipe 14.
The temperature of the wick 4 can be made lower than that of FIG. 2 by joining the wick 4 to the wick 4. This makes wick 4
Also, the temperature of the liquid 13 in the liquid ring 15 can be supercooled, and the liquid can operate normally even if the heat flux is large as in FIG. It goes without saying that the partition wall 18 can achieve the intended purpose even if the partition wall 18 is integrated with the wick 4 or the liquid pipe 14.

Embodiment 2. FIG. 4 is a diagram showing a cross section of an evaporator of a loop heat pipe showing a second embodiment of the present invention. Reference numeral 19 is a recess provided in the steam flow path 7 of the wick 4. The joint portion between the wick 4 and the evaporator container 5 where the working fluid evaporates due to the recessed notch and the vapor flow path 7
The distance between and becomes short, and the pressure loss here becomes small.
Moreover, the cross-sectional area of the vapor flow path 7 becomes large, and the pressure loss becomes small. This can improve the heat transport ability. Although the concave portion is shown as a triangular shape in the drawing, it goes without saying that the intended purpose can be achieved even if the concave portion is not a triangular shape.

Embodiment 3 FIG. 5 is a diagram showing a cross section of an evaporator of a loop heat pipe showing a third embodiment of the present invention. Reference numeral 20 denotes a recess provided on the liquid ring 15 side of the wick 4 and adjacent to the joint with the evaporator container 5. This concave cutout shortens the distance from the liquid ring 15 to the joint between the wick 4 and the evaporator container 5 where the working fluid evaporates.
The pressure loss here becomes small. This can improve the heat transport ability. Although the concave portion is shown as a triangular shape in the drawing, it goes without saying that the intended purpose can be achieved even if the concave portion is not a triangular shape.

Embodiment 4 FIG. 6 is a cross-sectional view of the loop heat pipe evaporator according to the fourth embodiment of the present invention. At the same time when the partition wall 18 is attached to the liquid pipe 14, a recess is provided in the portion of the steam flow path 7 of the wick 4. As a result, even in a space under a zero-gravity environment, even if the heat flux is large, it operates normally and the heat transport capacity can be improved. In addition, pressure loss between the wick 4 from which the working fluid evaporates, the joint between the evaporator container 5 and the steam flow path 7 and the steam flow path 7 is reduced, and the heat transport capacity can be improved. Although the partition wall 18 is not joined to the wick 4 and the recess is triangular in the figure in the figure, the intended purpose can be achieved even if the partition wall 18 is joined to the wick 4 and the recess is not triangular. It goes without saying that you can do it.

Embodiment 5. Embodiment 5 FIG. 7 is a diagram showing a cross section of an evaporator of a loop heat pipe showing Embodiment 5 of the present invention. At the same time that the partition wall 18 is attached to the liquid pipe 14, recesses are provided on the liquid ring 15 side of the wick 4 and adjacent to the joint with the evaporator container 5. As a result, even in a space under a zero-gravity environment, even if the heat flux is large, it operates normally and the heat transport capacity can be improved. Further, the pressure loss between the wick 4 and the evaporator container 5 where the working fluid evaporates from the liquid ring 15 becomes small, and the heat transport capacity can be improved.
In the figure, the partition wall 18 is not joined to the wick 4,
Although the recess has an example of a triangle, it goes without saying that the intended purpose can be achieved even if the partition wall 18 is joined to the wick 4 and the recess is not a triangle.

Embodiment 6 FIG. FIG. 8 is a diagram showing a cross section of an evaporator of a loop heat pipe showing a sixth embodiment of the present invention. The portion of the steam flow path 7 of the wick 4 and the wick 4
By providing recesses on the liquid ring 15 side and adjacent to the joint with the evaporator container 5, the distance from the joint between the wick 4 and the evaporator container 5 where the working fluid evaporates to the vapor flow path 7 The distance from the ring 15 to the joint between the wick 4 where the working fluid evaporates and the evaporator container 5 becomes shorter, and the pressure loss becomes smaller. In addition, the cross-sectional area of the steam flow path 7 becomes large, and the pressure loss here becomes small. This can improve the heat transport ability. Although the concave portion is shown as a triangular shape in the drawing, it goes without saying that the intended purpose can be achieved even if the concave portion is not a triangular shape.

Embodiment 7 FIG. 9 is a diagram showing a cross section of an evaporator of a loop heat pipe showing a seventh embodiment of the present invention. A partition wall 18 is attached to the liquid pipe 14, and a recess is provided in the portion of the steam flow path 7 of the wick 4. Further, recesses are provided on the liquid ring 15 side of the wick 4 and adjacent to the joint with the evaporator container 5, respectively. As a result, even in a space under a zero-gravity environment, even if the heat flux is large, it operates normally and the heat transport capacity can be improved. At the same time, the pressure between the wick 4 from which the working fluid evaporates and the joint between the evaporator container 5 and the vapor flow path 7 and between the wick 4 from which the working fluid evaporates from the liquid ring 15 and the joint between the evaporator container 5 Both losses are small. In addition, the cross-sectional area of the steam flow path 7 becomes large, and the pressure loss here becomes small. This can improve the heat transport ability. Although the partition wall 18 is not joined to the wick 4 and the recesses 19 and 20 have a triangular shape in the drawing,
It goes without saying that even if the partition wall 18 is joined to the wick 4, the intended purpose can be achieved even if the recess is not triangular.

[0025]

According to the present invention, the liquid temperature of the working fluid in the wick and the liquid ring is lowered, and boiling does not occur from the liquid ring side surface of the wick. Therefore, even in a space under a zero-gravity environment, vapor, which is the working fluid that has evaporated, does not cover the surface of the wick, and it operates normally even if the heat flux is large, and the heat transport capacity can be improved. .

According to the present invention, the pressure loss between the steam flow passage and the pressure loss from the joint between the wick and the evaporator container is reduced. This has the effect of improving the heat transport capacity.

According to the present invention, the pressure loss between the joint between the wick and the evaporator container where the working fluid evaporates from the liquid ring is reduced. This has the effect of improving the heat transport capacity.

According to the present invention, vapor, which is the working fluid that has been evaporated, does not cover the surface of the wick even in space under a zero-gravity environment, and the wick operates normally even if the heat flux is large, and the heat transport capacity is improved. At the same time, it is possible to reduce the pressure loss between the steam passage and the steam passage from the joint between the wick and the evaporator container, and improve the heat transport capacity. The effect is that you can do it.

According to the present invention, vapor, which is the working fluid that has been evaporated, does not cover the surface of the wick even in space under a zero-gravity environment, and the wick operates normally even if the heat flux is large, thereby improving the heat transport capacity. At the same time, there is an effect that the pressure loss between the wick where the working fluid evaporates from the liquid ring and the junction portion of the evaporator container can be reduced, and the heat transport capacity can be improved. .

According to the present invention, the pressure loss from the joint between the wick and the evaporator container to the vapor passage, the pressure loss in the vapor passage, and the joint between the wick where the working fluid evaporates from the liquid ring and the evaporator container. Both the pressure loss up to the part decreases.
This has the effect of improving the heat transport capacity.

According to the present invention, vapor, which is the working fluid that has evaporated, does not cover the surface of the wick even in space under a zero-gravity environment, and the wick operates normally even when the heat flux is large, thereby improving the heat transport capacity. The effect is that you can.
In addition, the pressure loss from the joint between the wick and the evaporator container to the vapor flow path, the pressure loss in the vapor flow path, and the pressure loss from the liquid ring to the joint between the wick and the evaporator container where the working fluid evaporates are both There is an effect that it becomes smaller and the heat transport capacity can be improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of a loop heat pipe according to the present invention.

FIG. 2 is a sectional view of the evaporator showing the first embodiment of the loop heat pipe according to the present invention.

FIG. 3 is a sectional view of an evaporator showing a first embodiment of a loop heat pipe according to the present invention.

FIG. 4 is a sectional view of an evaporator showing a second embodiment of a loop heat pipe according to the present invention.

FIG. 5 is a sectional view of an evaporator showing a third embodiment of the loop heat pipe according to the present invention.

FIG. 6 is a sectional view of an evaporator showing a fourth embodiment of the loop heat pipe according to the present invention.

FIG. 7 is a sectional view of an evaporator showing a fifth embodiment of a loop heat pipe according to the present invention.

FIG. 8 is a sectional view of an evaporator showing a sixth embodiment of the loop heat pipe according to the present invention.

FIG. 9 is a sectional view of an evaporator showing a seventh embodiment of a loop heat pipe according to the present invention.

FIG. 10 is a sectional view showing a conventional loop heat pipe.

FIG. 11 is a cross-sectional view showing a conventional loop heat pipe evaporator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 evaporator, 2 condenser, 3 arrow which shows the flow of applied heat, 4 wick, 5 evaporator container, 6 vapor of working fluid, 7 vapor flow path, 8 vapor pipe, 9 arrow which shows vapor flow, 10 Condensation ring, 11 Arrows showing outflow of heat, 12 Condenser container, 13 Working fluid liquid, 14
Liquid pipe, 15 liquid ring, 16 upper reservoir, 17 lower reservoir, 18 partition wall, 19 wick recess, 20
The recess of the wick.

Claims (7)

[Claims] 1. An evaporator, a condenser, a working fluid, a liquid pipe for connecting the evaporator and the condenser to allow a working fluid in a liquid phase to flow, and an evaporator and a condenser for connecting a vapor phase to operate. A loop heat pipe comprising a steam pipe through which a fluid flows, wherein a partition wall is attached to the liquid pipe in the evaporator. 2. An evaporator, a condenser, a working fluid, a liquid pipe for connecting the evaporator and the condenser, through which a working fluid in a liquid phase flows, and an evaporator, a condenser for connecting the evaporator and the condenser, and operating in a vapor phase. A loop heat pipe comprising a steam pipe through which a fluid flows, characterized in that a recess is provided in a steam flow passage portion of a wick included in the evaporator. 3. An evaporator, a condenser, a working fluid, a liquid pipe for connecting the evaporator and the condenser to allow a working fluid in a liquid phase to flow, and an evaporator and a condenser for connecting a vapor phase to operate. A loop heat pipe comprising a steam pipe through which a fluid flows, characterized in that a recess is provided on a liquid ring side of a wick provided in the evaporator and adjacent to a joint with the evaporator. 4. An evaporator, a condenser, a working fluid, a liquid pipe connecting the evaporator and the condenser to allow a working fluid in a liquid phase to flow, and connecting the evaporator and the condenser to operate in a vapor phase. A loop heat pipe composed of a vapor pipe through which a fluid flows, characterized by having a partition wall attached to a liquid pipe of the evaporator, and a concave portion provided in an evaporation passage portion of a wick of the evaporator. Loop heat pipe to do. 5. An evaporator, a condenser, a working fluid, a liquid pipe for connecting the evaporator and the condenser to allow a working fluid in a liquid phase to flow, and an evaporator and a condenser for connecting a vapor phase to operate. In a loop heat pipe composed of a steam pipe through which a fluid flows, a partition wall attached to the liquid pipe of the evaporator and a liquid ring side of the wick of the evaporator, and next to a joint with the evaporator. A loop heat pipe having a recess provided therein. 6. An evaporator, a condenser, a working fluid, a liquid pipe for connecting the evaporator and the condenser to allow a working fluid in a liquid phase to flow, and an evaporator and a condenser for connecting a vapor phase to operate. In a loop heat pipe composed of a steam pipe through which a fluid flows, a concave portion provided in a vapor flow path portion of a wick provided in the evaporator, and a liquid ring side of the wick and next to a joint portion with the evaporator. A loop heat pipe having a recess provided therein. 7. The loop heat pipe according to claim 4, wherein a concave portion is provided on the liquid ring side of the wick and adjacent to a joint portion with the evaporator.