JPH0949690A - Thermo siphon - Google Patents

Abstract

(57) Abstract: In a thermosiphon, a working fluid is not uniformly dispersed in the inner peripheral direction of an evaporation pipe. SOLUTION: A condensing part 14 that radiates heat to the outside is connected to an upper end part of an evaporation pipe 13 that is vertically arranged with a lower end part inserted in a high temperature heat source part 15. A liquid return pipe 17 is provided below the condensing portion 14 in communication with the liquid reservoir 18, and a liquid return pipe 17 is provided with an outlet 20 which is supplied from the liquid reservoir 18 and penetrates the pipe wall. In the thermosiphon, which is disposed inside 13 along the axial direction thereof and in which a condensable working fluid 16 is enclosed, an injection port 22 that opens in a substantially tangential direction is provided at the outer peripheral portion of the liquid return pipe 17. The rotating body 21 provided is rotatably fitted. In addition, the working fluid 16 in a liquid phase is supplied to the inside of the rotating body 21 through the outlet 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosiphon used for extracting geothermal heat.

[0002]

2. Description of the Related Art As is well known, a thermosiphon encloses a condensable fluid such as water or alcohol as a working fluid inside a sealed tube in which a non-condensable gas such as air is degassed by vacuum.
The hermetically sealed tube is installed along the vertical direction, and the lower end portion side thereof serves as a heat absorbing portion for giving heat from the outside, and the upper end portion side serves as a heat radiating portion for absorbing heat. Therefore, the working fluid inside evaporates due to the heat given to the heat absorbing section,
The vapor flows to the heat radiating portion and then radiates heat and condenses, thereby transporting heat as latent heat of the working fluid, and the liquefied working fluid returns to the heat absorbing portion as a liquid film flow due to gravity. Therefore, the thermosiphon can perform heat transfer from the bottom to the top without power.

The schematic structure is as shown in FIG. That is, the thermosiphon 1 shown here evaporates the condensed working fluid A, and the evaporation tube 3 that constitutes the heat absorbing section 2, the vapor flow tube 5 that guides the vapor of the working fluid A generated therein to the heat radiating section 4. The container is formed by a closed tube including a liquid return tube 6 that is supplied to the bottom of the tube 3. Evaporation tube 3
Is a long straight pipe whose upper and lower ends are hermetically sealed, and is disposed, for example, in a high temperature portion in the ground along the vertical direction. The vapor flow pipe 5 is connected to the upper end of the vaporization pipe 3 and extends laterally and is bent downward at a predetermined position.

The lower end of the steam flow pipe 5 has a large diameter,
The reservoir 7 is formed here. A jacket 8 for flowing a heat receiving medium such as water or air is attached to a portion of the vapor flow pipe 5 slightly above the reservoir 7 and serves as a heat radiating portion 4. A liquid return pipe 6 is provided at the bottom of the reservoir 7 via a flow rate adjusting valve 9.
Is connected.

The liquid return pipe 6 penetrates from the outside to the inside of the evaporation pipe 3, and a plurality of injection holes 10 equidistant from each other are arranged in series in the axial direction at the lower end of the inserted portion. It is provided. In addition, this injection hole 10 depends on factors such as the scale of the thermosiphon itself and the maximum heat transfer amount.
The diameter, the number, the arrangement and the like are set appropriately. A working fluid A that evaporates and condenses at a target temperature of water, alcohol, or the like in a state in which the non-condensable gas is degassed is provided inside the closed tube including the evaporation tube 3, the vapor flow tube 5 and the liquid return tube 6. Is enclosed. That is, in supplying the liquid phase working fluid A from the liquid return pipe 6 side to the evaporation pipe 3 side, the thermosiphon 1 described above causes the head pressure of the liquid phase working fluid A to move from each injection hole 10 to the inner surface of the evaporation pipe 3. It is configured to spray.

[0006]

However, in the thermosiphon 1 described above, since the plurality of injection holes 10 are provided in series in the axial direction of the liquid return pipe 6, the evaporation pipe 3
There is a possibility that the working fluid A may be sprayed only on the inner wall surface of No. 1 and the vicinity of the injection hole 10 and its vicinity. In other words, the working fluid A cannot be spread over a wide area in the circumferential direction of the evaporation pipe 3, and therefore, in the long thermosiphon 1 described above, insufficient supply of the working fluid A to the heat input portion, so-called dryout occurs. There is a risk that heat transfer may not be performed properly.

Therefore, conventionally, there is also a liquid return pipe 6 in which each injection hole 10 is displaced in the circumferential direction, but in that case as well, the working fluid A in the liquid phase flowing down the pipe wall is dispersed in a thin film in the inner circumferential direction. It is rarely thrown away, that is, it easily flows down into some streaks. Therefore, the working fluid A is satisfactorily ejected only from the limited ejection holes 10 among many, and as a result,
After all, it was not possible to evenly disperse in the inner peripheral direction of the evaporation tube 3.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a thermosiphon capable of uniformly and sufficiently refluxing a working fluid over a wide range of the inner peripheral surface of an evaporation pipe. is there.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention has an upper end portion of an evaporation pipe which is vertically arranged with the lower end portion inserted in a high temperature heat source portion. , A liquid that is connected to a condenser that radiates heat to the outside, and that is provided with a liquid reservoir below the condenser and that is provided with an outlet that is supplied from the liquid reservoir and that penetrates the pipe wall. In a thermosiphon in which a return pipe is disposed inside the evaporation pipe along the axial direction thereof, and further, a condensable working fluid is enclosed, the return pipe is opened substantially tangentially to the outer peripheral portion of the liquid return pipe. A rotary body having the above injection port is rotatably fitted, and a working fluid in a liquid phase is supplied to the inside of the rotary body through the outlet. To do.

According to the present invention, the working fluid is heated by the heat source portion on the lower end side of the evaporation tube to evaporate, rises toward the low-temperature low-pressure condenser section, and radiates heat to the outside to condense. To do. The working fluid in the liquid phase again flows into the liquid reservoir due to gravity, and then flows down the inner wall surface of the liquid return pipe. The working fluid is sent from the outflow port to the inside of the rotating body, and is further ejected from the ejection port toward the inner wall surface of the evaporation pipe. At this time, since the injection port is opened to the outer peripheral portion of the rotating body in a substantially tangential direction, the rotating body rotates in the fixed direction on the outer peripheral portion of the liquid return pipe due to the reaction of the injection.
In other words, the rotating body rotates within a predetermined range while ejecting the working fluid around the liquid return pipe as an axis, so that the working fluid is substantially evenly distributed over a wide range in the circumferential direction of the inner wall surface of the evaporation pipe.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described more specifically with reference to the accompanying drawings. FIG. 1 is a schematic diagram showing the principle of a specific example according to the present invention. A container of a thermosiphon 11 shown here is an evaporation pipe 13 having a lower end part as an evaporation part 12 and an upper end part as a condensing part 14. Are formed from. More specifically, the evaporation pipe 13 is a large-diameter and long straight tubular or corrugated metal pipe whose upper and lower ends are hermetically sealed. For example, a high temperature part 15 in the ground as a heat source part and a lower end thereof. It is arranged along the vertical direction with the parts inserted. Then, inside the evaporation pipe 13,
A working fluid 16 that evaporates and condenses at a target temperature such as water or alcohol in a state where the non-condensable gas is degassed is enclosed.

The upper end of the evaporation pipe 13 is slightly extended laterally, and the condenser 14 radiates heat to the outside.
It has become. Further, a large-diameter portion is formed below the condensing portion 14, and this serves as a reservoir 18 for temporarily storing the liquid-phase working fluid 16. Therefore, the reservoir 18 communicates with the condensing unit 14, and the condensing unit 14 is connected to the evaporator pipe 1.
It communicates with 3.

A base end portion of a liquid return pipe 17 made of a straight pipe-shaped metal pipe having a circular cross section is communicated with the bottom portion of the reservoir 18, and the front end portion side of the liquid return pipe 17 is arranged in the longitudinal direction. Spacers attached at predetermined intervals (not shown)
Is suspended in the inner space of the evaporation pipe 13 along the central axis thereof. The liquid return pipe 17 is provided with a plurality of outlets 20 penetrating the wall surface at equal intervals in series in the axial direction. Further, the liquid phase working fluid 16 is provided between the reservoir 18 and the liquid return pipe 17.
A valve 19 for adjusting the flow rate of is provided.

A sprinkler portion 21 as a rotating body is fitted to the outer peripheral portion of each outlet 20 of the liquid return pipe 17. As shown in FIGS. 2 and 3, the sprinkler portion 21 has a substantially cylindrical main body portion 2 having an injection port 22 described later.
3, a ball bearing 24, and a packing 25.

The back side of the outer ring of the ball bearing 24 is integrally fixed to the inner peripheral surface of the main body portion 23. Here, two ball bearings 24 are provided for each sprinkler portion 21. Further the main body 23
Is supported at its lower end by an annular support member 27 fixed to the liquid return pipe 17, and a contact point between the two is provided with lubricating means such as filling with grease. Therefore, the sprinkler portion 21 is configured to freely and smoothly rotate the outer peripheral portion of the liquid return pipe 17.
An injection port 22 is provided at a central portion in the height direction of the main body portion 23, the wall surface of the main body portion 23 penetrating and opening in the tangential direction of the outer peripheral portion of the liquid return pipe 17. The injection ports 22 have a circular shape here, and are provided at two locations on the sprinkler portion 21 in a state of being displaced in the circumferential direction.

Further, the end faces of the ball bearings 24 facing each other, and the inner ring of each ball bearing 24 and the outer wall surface of the liquid return pipe 17 are sealed by a ring-shaped packing 25 or the like. Therefore, the space between the two packings 25 facing each other vertically is the gap 26 between the inner surface of the main body 23 and the outer surface of the liquid return pipe 17.
Is formed over both circumferential directions. That is, the injection port 22 and the outflow port 20 communicate with each other through the gap 26.

Therefore, in order to operate the thermosiphon 11 configured as described above, the valve 19 is first opened to a predetermined opening. Then, the working fluid 16 stored in the reservoir 18 flows down on the wall surface of the evaporation pipe 16 by gravity, and is sequentially ejected from each outlet 20 to the main body 23 side. Here, with respect to the position of each outlet 20, each injection port 2
Since there is a case where the position of 2 is displaced in the circumferential direction, the jet flow of the working fluid 16 collides with the wall surface of one of the injection ports 22 outside the central axis side of the liquid return pipe 17. Or collide with the inner wall surface of the main body 23.

Further, the jet flow of the working fluid 16 is guided as it is to the jet port 22, and the evaporation pipe 13 is led from the opening thereof.
Or the space 26
After flowing along, it flows into the injection port 22 located in the vicinity and is similarly injected from there. That is, the working fluid 1
The jet flow of No. 6 is forcibly diverted to the tangential direction of the liquid return pipe 17 by the jet port 22. Then, due to the reaction of the injection, each sprinkler unit 21 causes the liquid return pipe 17 to move.
The outer peripheral portion of is rotated in a predetermined range in the direction of the arrow in FIG. In other words, each sprinkler part 21 injects the working fluid 16 while rotating in a fixed direction.

The working fluid 16 sprayed toward the inner surface of the evaporation pipe 13 is heated by the geothermal heat to evaporate, and rises toward the condensation section 14 having a low internal pressure. Then, the working fluid vapor 16 is deprived of heat to the outside air and becomes a liquid phase again, but is not stored in the reservoir 18 because the valve 19 is open, and is sent to each injection port 26 and evaporated from there. It is jetted toward the pipe 13. After that, the same cycle is continued until the valve 19 is closed.

In this way, each outlet 20 of the liquid return pipe 17
The sprinkler parts 21 are provided on the outer periphery of the
In addition, since each sprinkler unit 21 injects the working fluid 16 while reliably rotating even if the positions of the outflow port 20 and the ejection port 22 are displaced from each other, the sprinkler unit 21 can spread over a wide range in the lengthwise and circumferential directions of the evaporation pipe 13. The working fluid 16 can be sprayed reliably and uniformly. In addition, the thermosiphon 1
The heat transport power of 1 becomes good.

In the above embodiment, a part of the liquid return pipe 17 is arranged outside the evaporation pipe 13, and the underground high temperature portion 15 is exemplified as the heat source portion. The configuration is not limited to the example, and the liquid return pipe 17 may be provided inside the evaporation pipe 13, and the heat source unit may be an appropriate heating unit.

[0022]

As described above, according to the present invention, the rotating body having the injection port opened substantially tangentially is rotatably fitted to the outer peripheral portion of the liquid return pipe, and the rotating body is Since the working fluid in the liquid phase is supplied to the inside through the outflow port, the working fluid in the liquid phase can be supplied almost uniformly to a wide range in the inner circumferential direction of the evaporation pipe, Therefore, the heat transporting power can be improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a specific example according to the present invention.

FIG. 2 is a schematic view showing a state in which a liquid return pipe and a sprinkler unit are assembled together with a part thereof cut away.

3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is a schematic view showing a general long thermosiphon.

[Explanation of symbols]

11 ... Thermo siphon, 13 ... Evaporation pipe, 14 ... Condensing part, 15 ... High temperature part, 16 ... Working fluid, 17 ... Liquid return pipe, 18 ... Reservoir, 20 ... Outflow port, 21 ... Sprinkler part, 22 ... Injection port.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuji Saito 1-5-1, Kiba, Koto-ku, Tokyo Inside Fujikura Ltd.

Claims (1)

[Claims] 1. A condensing part for radiating heat to the outside is communicated with an upper end of an evaporation pipe which is vertically arranged with the lower end inserted in a high-temperature heat source part, and a liquid pool is provided below the condensing part. A liquid return pipe, which is provided in communication with each other, is provided with an outflow port which is supplied with liquid from the liquid reservoir and penetrates through the pipe wall, is arranged inside the evaporation pipe along its axial direction. In the thermosiphon further filled with a condensable working fluid, a rotating body having an injection port opened substantially tangentially is rotatably fitted to an outer peripheral portion of the liquid return pipe, and A thermosyphon characterized in that a working fluid in a liquid phase is supplied to the inside of a rotating body through the outlet.