JPH04103993A - Double loop type heat exchanger - Google Patents

Abstract

PURPOSE:To take out optionally once accumulated heat by a method wherein a heat accumulating part of a primary loop may also act as an evaporator of the secondary loop. CONSTITUTION:In the event that heat is accumulated in a heat accumulating part 15 of a primary loop 12, valves V1 and V2 are closed and valves V3 and V4 are released, and then a heating part 14 filled with the working liquid is heated. The heated working liquid circulates automatically within the loop 12 and the heat is gradually accumulated at a heat accumulating part 15. In the event that the accumulated heat is taken out, valves V3 and V4 are closed and valves V1 and V2 are released, the primary loop side 12 is closed and the secondary loop side 13 is opened. The heat accumulating part 15 is a heating part and then the working liquid heated there evaporates and the liquid is thermally transferred to a condensing part 20. The heat is removed there. The liquid is condensed and again the liquid is returned back to operating liquid of liquid phase and circulates back to the heating part. At this time, a supplying of the working liquid is made stable by a liquid reservoir 21 and at the same time a drying-out of it is prevented. Accordingly, the heat taken out at the condensing part 20 is utilized to change water, for example, into hot water.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a double-loop heat exchanger with two heat cycle systems for taking in and storing heat and extracting the stored heat. be.

BACKGROUND OF THE INVENTION As shown in FIG. 2, in a conventional loop-type heat vibrator 1, a working fluid sealed in a loop is heated in a heating section 2 to become steam, and this steam rises inside the loop to cool it. Generally, the working fluid condensed and liquefied in the section 3 flows back downward within the loop, and is heated again in the heating section to turn into steam and rise within the loop toward the cooling section 3.

In addition, when two conventional loop-type heat vibrators are used in combination, in the case of one (lower in FIG. 3) loop-type heat vibrator (heat-receiving loop) 4, the heat is heated in the heating section 6. The vapor of the working fluid evaporated is deprived of heat and condensed in the heat storage section 7, returns to a liquid phase, and is heated again in the heating section 6. This operation is repeated. In addition, in the case of the other loop type heat vibe (heat dissipation loop) 5, the heating part 8 is connected to the heat storage part 7 of the loop type heat vibe 4.
It is arranged so that heat exchange is possible between the two. The vapor of the working fluid heated in the heating section 8 is deprived of heat and condensed in the cooling section 9, becoming a liquid-phase working fluid and flowing back to the heating section 8.

The heat extracted in the cooling section 9 is extracted and used in the form of hot water obtained by heating water, for example.

Further, in the conventional loop heat pipe, two independent loops are used, and one of the loop heat pipes 5 transports heat from the heating section to the heat storage section. In such a case,
Since two or more heat exchangers (the heat storage section 15 of the heat receiving loop and the evaporation section of the heat radiation loop) are required for one heat storage section, there is a problem that the heat storage section becomes large.

This invention was made in view of the above circumstances, and aims to provide a heat exchanger that can reduce the number of heat exchangers used and can arbitrarily take out the heat that has been stored.

Means for Solving the Problems As a means for solving the above problems, the double loop heat exchanger of the present invention has a heating section that is heated from the outside and a heat storage section that exchanges heat with a heat storage body. The primary loop, which is filled with a working fluid that circulates naturally due to the temperature difference, communicates with the primary loop to form a circulation path, and the heat storage section and the cooling section located at a higher position and dissipating heat to the outside are connected to each other to absorb the latent heat of vaporization of the working fluid. The heat storage section and the primary loop or the secondary loop communicate with each other to form a circulation path.
Communication with the secondary loop is switched by a valve, and a liquid reservoir is provided below the cooling section of the secondary loop.

Function: In this double-loop heat exchanger, when storing heat in the heat storage section of the primary loop, the heating section of the primary loop filled with working fluid is heated by operating a valve. The heated working fluid naturally circulates within the primary loop and is transferred as sensible heat between the heating section and the heat storage section, and is stored in the heat storage section. In addition, when taking out the heat stored in the heat storage section of the primary loop, the valve is operated to close the primary loop side filled with working fluid and open the secondary loop side instead.

In the secondary loop, the heat storage section of the primary loop serves as a heating section, and only the lower heating section is formed in a vacuum with working fluid. Therefore, the secondary loop operates as a normal loop-type heat pipe, and the working fluid heated by the heat of the heat storage body evaporates, becomes vapor of the working fluid, and transports the heat as latent heat to the cooling section. The vapor of the working fluid is then deprived of heat, condenses and returns to the liquid phase of the working fluid, and returns to the heating section via the fluid reservoir. Therefore, heat is extracted and utilized in the cooling section of the secondary loop.

Further, since the liquid reservoir is provided below the cooling section of the secondary loop, the supply of working fluid to the heat storage section is stabilized when the secondary loop is communicated with, and dryout is prevented.

Embodiment Hereinafter, an embodiment of the present invention will be described based on FIG.

The double loop heat exchanger 11 using a heat vibrator has 1
It is composed of a secondary loop 12 and a secondary loop 13.

This primary loop 12 is formed into a closed loop by connecting the heating section 14 and the heat storage section 15 with a pipe 16, and the inside of the primary loop 12 consisting of the heating section 14, the heat storage section 15, and the pipe 16 is condensed. It is filled with hydraulic fluid. Further, a valve v3 and a valve v4 are provided on the upstream and downstream sides of the heat storage section 15 of the first loop 12. Further, further upstream of the upstream valve v3, a pipe 17 is connected for filling a working fluid, such as Freon N3, etc., and an expansion tank 18 is connected to this pipe 17 at a position higher than the heat storage section 15. The end thereof is closed with a valve. This expansion tank 18 absorbs changes in the volume of the working fluid, and is also formed with a transparent window (not shown) to increase the level of the working fluid filled in the primary loop 12. The hydraulic fluid can be visually checked, and when the fluid level drops, the hydraulic fluid is replenished from the valve.

Further, the secondary loop 1 provided above the primary loop 12
3 is provided with one end of the pipe 19 upstream of the heat storage section 15 of the primary loop 12 and downstream of the valve v3 at a height approximately equal to the level of the working fluid in the primary loop 12. The other end is connected to the heat storage section 1 through the valve 1.
5 and upstream of valve 4 through a valve v2 provided at a position lower than the level of the working fluid in the primary loop 12, and downstream of valve Vl,
A condensing section 20, which is a heat exchanger that extracts heat, and a liquid reservoir 21 downstream of the condensing section 20, which collects and stores condensed working fluid,
They are each interposed at a position higher than the level of the hydraulic fluid filled in the primary loop 12.

Then, the valve ■3 and valve ■4 of the primary loop
By closing and creating a vacuum, the heat storage section 16 and the valve V
l, condensing section 20. A closed secondary loop 13 is formed by the liquid reservoir 21 and the valve 2. In addition, the heating section 14. A thermometer T1 is installed immediately before the upstream side and immediately after the downstream side of the heat storage section 15 and the condensing section 20 to measure the temperature of the working fluid (working fluid or its vapor) moving within the primary loop 12 and the secondary loop 13. ~T6 is provided.

Next, the operation of this embodiment configured as described above will be explained.

When storing heat in the heat storage section 15 of the primary loop 12, this double-loop heat exchanger 11 is configured to
Heating section 1 of primary loop 12 filled with hydraulic fluid with valve v2 closed and valve V3 and valve v4 open.
Heat 4. The heated working fluid reaches a high temperature, naturally circulates within the primary loop 12, and is transferred to the heat storage section 15 as sensible heat, and is gradually stored in the heat storage section 15.

Further, when taking out the heat accumulated in the heat storage section 15 of the primary loop 12, the valve V3. Close valve V4,
Open the valves Vl and V2 to close the primary loop 12 side filled with hydraulic fluid, and instead open the upper secondary loop 13 side. In the secondary loop 13, the heat storage section 15 becomes a heating section when the primary loop 12 is operated, and is formed so that only the lower heating section contains the working fluid. Therefore, the secondary loop 13 operates as a normal loop-type heat pipe, and the working fluid heated in the heat storage section 15 evaporates, and the heat is transferred to the condensation section 20 as latent heat of vapor. Then, in the condensing section 20, the liquid is decondensed and condensed, returns to a liquid phase working fluid, and is refluxed to the heating section. At this time,
Since the liquid reservoir 21 is interposed in the secondary loop,
When connected, the supply of working fluid to the heat storage part is stabilized, and
Dryout is prevented.

Therefore, the heat extracted in the condensing section 20 of the secondary loop 13 is used to convert, for example, water into hot water.

Therefore, according to the double loop heat exchanger 11 of this embodiment, heat is recovered from surplus heat, waste heat with large load fluctuations, etc., and after being stored once, this accumulated heat can be used at any time. Moreover, it can be taken out stably. Furthermore, for example, solar heat stored in the summer can be effectively used as heat for melting snow and the like in the winter.

Effects of the Invention As explained above, the double loop heat exchanger of the present invention consists of a primary loop filled with working fluid and a secondary loop that operates as a loop heat vibrator. Since the heat storage section of the loop also serves as the evaporator of the secondary loop, the number of heat exchangers used can be reduced, making the device more compact, and switching between the primary and secondary loops can be done with a valve. Therefore, it is easy to recover and accumulate heat, and the heat stored in the heat storage section can be easily taken out at any time. In addition, a liquid reservoir is installed below the cooling section of the secondary loop, which makes it possible to extract stable heat during secondary loop operation, and prevents problems such as insufficient fusion heat and dryout caused by insufficient working fluid. It is possible to prevent the occurrence of defects.

[Brief explanation of the drawing]

Figure 1 is a system diagram showing an embodiment of the double loop heat exchanger of the present invention, Figure 2 is a system diagram of a conventional ordinary loop heat pipe, and Figure 3 is a system diagram of a conventional double loop heat exchanger. FIG. 2 is a system diagram showing an exchanger. 11...Double loop heat exchanger, 12...Primary loop, 13...Secondary loop, 14...Heating section,
15... Heat storage section, 20... Condensation section, 21...
Liquid reservoir, ■1~v4...Valve, T1~T6
···thermometer.

Claims (1)

[Claims] A heating section that is heated from the outside and a heat storage section that exchanges heat with the heat storage body are connected to form a circulation path through a primary loop filled with a working fluid that naturally circulates due to the temperature difference, and the heat storage section and a cooling section located at a higher position and dissipating heat to the outside are connected to form a circulation path by a secondary loop that transports heat using the latent heat of vaporization of the working fluid, and this heat storage section and the primary loop or the secondary loop communicate with each other to form a circulation path. A double loop heat exchanger, characterized in that communication with the secondary loop is switched by a valve, and a liquid reservoir is interposed below the cooling section of the secondary loop.