JPH0650233B2 - Double loop heat exchanger - Google Patents

Description

TECHNICAL FIELD The present invention relates to a double loop heat exchanger having two heat cycle systems for taking in and storing heat and taking out the stored heat. is there.

2. Description of the Related Art In a conventional loop heat pipe 1, as shown in FIG. 2, the working fluid enclosed in the loop is heated in a heating unit 2 to become steam, and this steam rises in the loop and is cooled. It is general that the working liquid condensed and liquefied in the part 3 is refluxed downward in the loop, and is heated again in the heating part to become vapor to rise in the loop toward the cooling part 3.

When two conventional loop heat pipes are used in combination, one of the loop heat pipes (lower in FIG. 3) (heat receiving loop) 4 is heated by the heating unit 6. The vapor of the working fluid that has been evaporated is deprived of heat in the heat storage section 7 and condensed, returns to the liquid phase, and is heated again in the heating section 6 to repeat the operation. In the case of the other loop type heat pipe (radiation loop) 5, the heating unit 8 is replaced by the heat storage unit 7 of the loop type heat pipe 4.
It is arranged so as to be able to exchange heat with. Then, the vapor of the working fluid heated in the heating section 8 is deprived of heat in the cooling section 9 and condensed, and becomes a working fluid in a liquid phase, and is returned to the heating section 8. The heat extracted in the cooling unit 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 loop heat pipe 5 transfers heat from the heating unit to the heat storage unit. In such cases,
Since one heat storage unit requires two or more heat exchangers (the heat storage unit 15 of the heat receiving loop and the evaporation unit of the heat radiation loop), there is a problem that the heat storage unit becomes large.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a heat exchanger that can reduce the number of heat exchangers to be used and can optionally take out the heat once 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 unit that is heated from the outside and a heat storage unit that exchanges heat between the heat storage unit. , The heat storage part and the cooling part located at a higher position and radiating heat to the outside, which are connected by a primary loop filled with the working liquid that naturally circulates due to the temperature difference, form a circulation path, A secondary loop for heat transfer is connected so as to form a circulation path, and this heat storage unit is connected to the primary loop or 2
The communication with the next loop is switched by a valve, and a liquid reservoir is provided below the cooling section of the secondary loop.

In this double loop heat exchanger, when heat is stored in the heat storage section of the primary loop, the heating section of the primary loop filled with the working fluid is heated by the valve operation. The heated hydraulic fluid naturally circulates in the primary loop, and is transferred as sensible heat between the heating unit and the heat storage unit to be stored in the heat storage unit. Further, when the heat stored in the heat storage section of the primary loop is taken out, the valve is operated to close the primary loop side filled with the 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 a vacuum having working fluid is formed only in the lower heating section. 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 is evaporated and becomes vapor of the working fluid to be transferred as latent heat to the cooling unit. Then, the vapor of the working fluid is deprived of heat, condenses and returns to the working fluid in the liquid phase again, and returns to the heating portion via the liquid reservoir. Therefore, heat is extracted and used in the cooling section of the secondary loop. Further, since the liquid reservoir is provided below the cooling part of the secondary loop, the supply of the working liquid to the heat storage part is stabilized and the dryout is prevented when the secondary loop is in communication.

Embodiment An embodiment of the present invention will be described below with reference to FIG.

The double loop type heat exchanger 11 using the heat pipe has one
It is composed of a secondary loop 12 and a secondary loop 13.
The primary loop 12 is formed into a closed loop by connecting the heating unit 14 and the heat storage unit 15 with a pipe 16, and the inside of the primary loop 12 including the heating unit 14, the heat storage unit 15 and the pipe 16 is condensed. It is filled with a working fluid. A valve V ₃ and a valve V ₄ are provided on the upstream side and the downstream side of the heat storage section 15 of the first loop 12. Further, a pipe 17 for filling a working fluid, for example, Freon 113, is connected further upstream of the valve V ₃ on the upstream side. The pipe 17 is provided with an expansion tank 18 at a position higher than the heat storage unit 15. Is provided and its end is closed by a valve. The expansion tank 18 absorbs a change in volume of the working fluid, and the expansion tank 18 has a transparent window portion (not shown) formed therein so that the liquid level of the working fluid filled in the primary loop 12 is increased. Is visible, and the hydraulic fluid is replenished from the valve when the liquid level drops.

In addition, the secondary loop 1 provided above the primary loop 12
3, one end of the pipe 19 is provided on the upstream side of the heat storage section 15 of the primary loop 12 and downstream of the valve V _{3 at} a height substantially equal to the liquid surface of the working fluid in the primary loop 12. Is connected via the valve V _1, and the other end is connected to the primary loop 12 downstream of the heat storage unit 15 and upstream of the valve V _4.
Valve V ₂ installed at a position lower than the liquid level of the working fluid inside
A condenser part 20 which is a heat exchanger for taking out heat and a liquid reservoir 21 which collects and collects the condensed working liquid are provided on the downstream side of the valve V _{1 on} the downstream side of the valve V _1. The loops 12 are respectively provided at positions higher than the liquid level of the hydraulic fluid.

Then, the valves V ₃ and V _{4 of the} primary loop
The heat storage unit 16 and the valve V
₁ , the condensing unit 20, the liquid reservoir 21, and the valve V ₂ form a secondary loop 13 in a sealed state. In addition, immediately before the upstream side and immediately after the downstream side of the heating unit 14, the heat storage unit 15a, and the condensing unit 20, respectively, the primary loop 1
Thermometers T _{1 to} T ₆ for measuring the temperature of the working fluid (working fluid or its vapor) moving in the secondary and secondary loops 13.
Is provided.

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

This double-loop heat exchanger 11 has a valve V ₁ , when storing heat in the heat storage unit 15 of the primary loop 12.
With the valve V ₂ closed and the valves V ₃ and V ₄ open, the heating section 14 of the primary loop 12 filled with the working fluid is heated. The heated hydraulic fluid becomes high in temperature and naturally circulates in the primary loop 12 to transfer heat to the heat storage section 15 as sensible heat and gradually store heat in the heat storage section 15.

When the heat stored in the heat storage section 15 of the primary loop 12 is taken out, the valves V ₃ and V ₄ are closed,
The valves V ₁ and V ₂ are opened to close the side of the primary loop 12 filled with hydraulic fluid, and open the side of the upper secondary loop 13 instead. In the secondary loop 13, the heat storage part 15 when the primary loop 12 is operated is a heating part, and the heating liquid is formed only in the lower heating part. Therefore, the secondary loop 13 operates as a normal loop heat pipe, the working liquid heated in the heat storage unit 15 evaporates, and is transferred to the condensation unit 20 as latent heat of vapor. Then, heat is taken away in the condensing unit 20 to condense and return to the liquid-phase working liquid again, and recirculate to the heating unit. At this time, since the liquid reservoir 21 is provided in the secondary loop, the supply of the working liquid to the heat storage unit is stable and the dryout is prevented during the communication.

Therefore, the heat taken out in the condensing section 20 of the secondary loop 13 is used to change, for example, water into warm 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 once stored, the accumulated heat is stored at any time. Moreover, it can be taken out stably. Further, for example, the solar heat stored in the summer can be effectively used as heat for snow melting in the winter.

EFFECTS OF THE INVENTION As described above, the double-loop heat exchanger of the present invention comprises a primary loop having a working fluid filled therein and a secondary loop operating as a loop heat pipe.
Since the heat storage part of the next loop also serves as the evaporator of the second loop, the number of heat exchangers used can be reduced, the size of the device can be reduced, and the switching between the primary loop and the secondary loop can be performed with a valve. Since it can be performed, the heat can be easily collected and stored, and the heat once stored in the heat storage section can be easily taken out at any time. Further, since the liquid reservoir is provided below the cooling unit of the secondary loop, stable heat can be taken out during the operation of the secondary loop, and insufficient heat of fusion or dryout caused by insufficient hydraulic fluid can occur. It is possible to prevent the occurrence of defects.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of a double loop heat exchanger of the present invention, FIG. 2 is a system diagram of a conventional ordinary loop heat pipe, and FIG. 3 is a conventional double loop heat exchanger. It is a system diagram which shows an exchanger. 11 ... Double loop heat exchanger, 12 ... Primary loop,
13 ...... secondary loop, 14 ...... heating unit, 15 ...... heat storage unit, 20 ...... condensing unit, 21 ...... liquid _reservoir, V 1 ~V ₄
...... Valve, T _{1 to} T ₆ ...... thermometer.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shotaro Yoshida 1-5-1, Kiba, Koto-ku, Tokyo Shigeru Kumagai, Examiner, Fujikura Electric Wire Co., Ltd. (56) Reference JP-A-2-254292 (JP, A) )

Claims (1)

[Claims] 1. A heating unit that is heated from the outside and a heat storage unit that exchanges heat with a heat storage body are connected to each other through a primary loop filled with a working fluid that naturally circulates due to a temperature difference so as to form a circulation path. The heat storage part and the cooling part located at a higher position and radiating heat to the outside are communicated so as to form a circulation path by a secondary loop that transfers heat by the latent heat of vaporization of the working liquid. A double-loop type characterized in that communication with the primary loop or the secondary loop is switched by a valve, and a liquid reservoir is provided below the cooling part of the secondary loop. Heat exchanger.