JPH01252834A - Coolant natural circulation type heat transferring device - Google Patents

Abstract

PURPOSE:To improve an efficiency of cooling capability within a wide temperature range even if a temperature difference between an indoor area and an outdoor area is substantially varied by a method wherein a coolant enclosing amount controlling means made variable in response to a temperature difference between an outdoor temperature and an indoor temperature is arranged in the midway of a liquid coolant pipe. CONSTITUTION:In case that a temperature difference DELTAT between an outdoor temperature T1 and an indoor temperature T2 is high, an amount of circulating coolant is calculated in a controller 14 in such a way as an efficiency of cooling capability may be increased. An actuator 11 is operated so as to be directed upwardly under an instruction from the controller 14, resulting in that an amount of coolant stored in a coolant storing container 10 is reduced. Thus, an amount of circulating coolant in a liquid coolant pipe 7 is increased, resulting in that a coolant liquid level is kept high. Thus, a difference in height of the coolant liquid surface is increased to show a value H, resulting in that a cooling pressure of the evaporator 1 is increased and a evaporating temperature of the coolant is increased. As a result, a difference between an evaporation temperature and a temperature T2 of cooled air (indoor side) around the evaporator 1 is decreased and a cooling capability is decreased. However, since a height difference (H) of the coolant liquid surface is high, so that the coolant circulating capability is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a natural refrigerant circulation heat transfer device that utilizes a natural refrigerant circulation cycle.

[Conventional technology]

Recently, there has been a demand for air conditioners that are energy efficient for rooms, such as computer rooms, which generate a high amount of internal heat and are subject to strict temperature and humidity conditions and air cleanliness. As one of the products that meet this demand, air conditioners that use a refrigerant natural circulation heat transfer device, which uses low-temperature air to transfer heat indoors to the outdoors, in conjunction with air conditioning equipment, are attracting attention.

The above-mentioned refrigerant natural circulation heat transfer device is also called a thermosiphon, and heat exchangers installed indoors and outdoors are connected in a ring shape with refrigerant piping, and a low boiling point refrigerant is sealed inside.

As such a natural refrigerant circulation type heat transfer device, for example, one disclosed in Japanese Utility Model Application Publication No. 79773 in 1983 is known (as shown in FIG. 6).

As shown in the figure, the refrigerant natural circulation heat transfer device 101 includes an evaporator 102 installed indoors, a condenser 103 placed above the evaporator 103 and installed outside the room, and an outlet of the evaporator 102. 102B and an inlet 103A of the condenser 103, and a light side refrigerant pipe 105 that connects the outlet 103B of the condenser 103 and the inlet 102A of the evaporator 102.

In the refrigerant natural circulation heat transfer device 101, the refrigerant is
It is heated by the warm indoor air in the evaporator 102,
Boil and evaporate. The indoor air is cooled by the latent heat of vaporization at this time. and evaporator 102. Gas side refrigerant piping 104. A fixed amount of refrigerant is circulated between the condenser 103 and the light side refrigerant pipe 105. The evaporated refrigerant becomes a gas and moves up the gas side refrigerant pipe 104, is led to the condenser 103, and is cooled by the cold outside air. The cooled refrigerant is condensed and liquefied to the light side refrigerant pipe 10.
5 and returns to the evaporator 102 again.

If the temperature outside the room is lower than the temperature inside the room, the refrigerant circulation described above is caused by the pressure difference caused by the phase change of the refrigerant and the difference in height of the refrigerant liquid level. This occurs due to the ring force, and the heat inside the room is released to the outside without any power.

Then, the natural circulation force mentioned above, the resistance of the piping system, and the heat exchanger (
Evaporator 102. The circulating amount of refrigerant is determined from the characteristics of @detector 103).

[Problems to be Solved by the Invention] In the conventional refrigerant natural circulation heat transfer device 101, the cooling capacity of the system is determined by the temperature difference between indoors and outdoors and the amount of refrigerant circulated.

Specifically, this cooling capacity may become unstable if the temperature difference between indoors and outdoors is small, but it increases almost in proportion to the temperature difference between indoors and outdoors. However, if the difference in height of the refrigerant liquid level is small, the natural circulation force will be small, and even if the heat exchanger (evaporator 102, condenser 103) has a margin, the cooling capacity will reach its upper limit.

The influence of this height difference in the refrigerant liquid level on the cooling capacity will be explained in detail.

When the height difference between the refrigerant liquid levels is large, the refrigerant pressure in the evaporator 102 becomes high, and the evaporation temperature of the refrigerant becomes high. Therefore, the difference between the evaporation temperature and the temperature of the cooled air (indoor side) around the evaporator 102 becomes smaller, and the cooling capacity becomes smaller. However, since the difference in height of the refrigerant liquid level is large, the refrigerant circulation capacity becomes large.

Therefore, the cooling capacity tends to be difficult to reach its upper limit.

The cooling capacity curve in this case is shown in FIG. 7(A).

On the other hand, when the height difference between the refrigerant liquid levels is small, the refrigerant pressure in the evaporator 102 becomes low (and the evaporation temperature of the refrigerant becomes low).

Therefore, the evaporation temperature and the cooled air around the evaporator 102 (
The difference between the temperature (indoor side) and the inside temperature increases, and the cooling capacity increases. However, since the difference in height of the refrigerant liquid level is small, the refrigerant circulation ability becomes small. Therefore, the cooling capacity tends to reach its upper limit. The cooling capacity curve in this case is the seventh
This is shown in (B) of the figure.

Therefore, the cooling capacity for a predetermined temperature difference is determined according to the height difference of the refrigerant liquid level.

Here, the evaporator 102. Gas side refrigerant piping 104° condenser 103. A fixed amount of sealed refrigerant is circulated between the downstream refrigerant pipes 1050, but if the amount of refrigerant sealed in this circulation is constant, the refrigerant is This will determine the difference in height of the liquid level.

However, in the conventional refrigerant natural circulation heat transfer device 101, its cooling capacity is determined only by the temperature difference between indoors and outdoors, which cannot be controlled in any way. The magnitude of the cooling capacity with respect to the temperature difference will only take either trend (A) or (B), and the efficiency of the cooling capacity will become low. Therefore,
If the temperature difference between indoors and outdoors changed significantly, the efficiency of the cooling capacity could drop.

The present invention was made to solve these conventional problems, and its purpose is to improve the efficiency of cooling capacity over a wide temperature range even when the temperature difference between indoors and outdoors changes significantly. The purpose of the present invention is to provide a mobile device.

[Means to solve the problem]

In order to achieve the above object, the present invention includes an evaporator installed indoors, an a-detector installed outside outdoors and located at a high place of the evaporator, and a It is equipped with a gas side refrigerant pipe that connects the inlet and a vent side refrigerant pipe that connects the condenser outlet and the evaporator inlet. In a refrigerant natural circulation heat transfer device that moves refrigerant to the outdoor side, there is a refrigerant that circulates in the middle of the ventral refrigerant piping so as to increase the efficiency of the cooling capacity against the temperature difference between the outdoor side and the indoor temperature. A refrigerant charge amount control means is provided to vary the amount of refrigerant in accordance with the temperature difference.

(Function) In the present invention, when the temperature difference between the outdoor temperature and the indoor temperature is large, the amount of refrigerant stored in the refrigerant charge amount control means is small, and the amount of refrigerant related to circulation is large. Therefore, the liquid level of the refrigerant becomes high, and the difference in height between the refrigerant liquid levels becomes large.

Therefore, the pressure of the refrigerant flowing into the evaporator increases, and the evaporation temperature of the refrigerant increases. As a result, the difference between the evaporation temperature and the temperature of the cooled air (indoor side) around the evaporator becomes smaller.
Cooling capacity decreases. However, 2 and 7, since the difference in height of the refrigerant liquid level is large, the refrigerant circulation capacity becomes large. Therefore, the cooling capacity tends to be difficult to reach its upper limit.

On the other hand, when the temperature difference is small, there are many stars in which the refrigerant is accommodated in the refrigerant filling amount control means, and the amount of refrigerant involved in circulation is reduced. Therefore, the liquid level of the refrigerant becomes low, and the difference in height between the refrigerant liquid levels becomes small.

Therefore, the refrigerant pressure in the evaporator becomes low, and the evaporation temperature of the refrigerant becomes low. As a result, the difference between the evaporation temperature and the temperature of the cooled air (indoor side) around the evaporator increases,
Cooling capacity increases. However, since the difference in height of the refrigerant liquid level is small, the refrigerant circulation ability becomes small. Therefore, the cooling capacity tends to reach its upper limit.

(Example〕 Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 show the contents of a natural refrigerant circulation type heat transfer device according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes an evaporator, which is installed inside the indoor unit 2 on the indoor side. , 3 is a condenser, and evaporator 1
It is located at a high place and has an outdoor unit on the outside... [・4
is installed inside. A blower 5 is arranged inside the indoor unit 1-2 and the outdoor unit 4, and the evaporator 1. It is located downstream of the condenser 3 at a position j~. 6 is a gas side refrigerant pipe, which connects the outlet IB of the evaporator 1 and the inlet 3A of the condenser 3.
Connect with. 7 is the ventral refrigerant pipe, which is connected to the outlet 3 of the condenser 3.
Connect B and the inlet IA of the generator l.

As shown in FIG. 2, a refrigerant filling amount control means 8 is provided in the middle of the vent side refrigerant pipe 7. This refrigerant filling amount control means 8 changes the flow of refrigerant to be circulated according to the temperature difference between the temperature outside the room and the temperature inside the room so as to increase the efficiency of the cooling capacity against the temperature difference between the outside temperature and the inside temperature. ,
It is composed of a refrigerant storage container IO that communicates with the ventral refrigerant pipe 7 via a communication pipe 9, and an actuator 11 that changes the volume of refrigerant stored inside the refrigerant storage container 10. Here, the refrigerant stored in the communication pipe 9 and the refrigerant storage container 10 remains in a state in contrast to the flow of refrigerant in the vent side refrigerant pipe 7, so that the refrigerant between the evaporator 1 and the condenser 3 It is designed so that it does not circulate between the two.

Reference numeral 12 denotes an outdoor temperature sensor that detects the outdoor temperature 'Fl. Reference numeral 13 denotes an indoor temperature detector that detects the temperature T2 on the indoor side. 14 is a controller 1 whose input side is connected to the outdoor temperature sensor 2S12 and the indoor temperature sensor 13, and whose output side is connected to the actuator 11.

Next, the operation of this embodiment will be explained in Figure 3 (1). This will be explained based on FIG.

First, in FIG. 1, the outdoor side temperature T3 is detected by the indoor side temperature detector 12, and the indoor side temperature detector 13! From this, the temperature T on the indoor side is detected. These temperature signals are sent to controller 14. In controller I4,
The temperature difference T between the temperature T1 on the outdoor side and the temperature Tt on the indoor side is calculated, and the amount of refrigerant to be circulated is calculated so as to increase the efficiency of the cooling capacity with respect to the temperature difference ΔT. and,
The actuator 1 is actuated so that the calculated amount of refrigerant is supplied to the liquid side refrigerant pipe 7 according to a command from the controller 14.
1 is activated.

For example, as shown in FIG. 3, the temperature T outside the room.

If the temperature difference ΔT between the temperature Tz and the temperature Tz on the indoor side is large,
In the controller 14, the amount of refrigerant to be circulated is calculated so as to increase the efficiency of the cooling capacity with respect to the temperature difference ΔT. In this case, the amount of circulating refrigerant is calculated to be large. Then, in response to a command from the controller 14, the actuator 11 operates upward, and the amount of refrigerant stored in the refrigerant storage container 10 decreases. Therefore, the amount of refrigerant circulating in the liquid side refrigerant pipe 7 increases, and the liquid level of the refrigerant becomes high. Therefore, the difference in height of the refrigerant liquid level becomes large and becomes H.

Therefore, the refrigerant pressure in the evaporator 1 increases, and the evaporation temperature of the refrigerant increases. As a result, the evaporation temperature and evaporator l
The difference between the temperature T2 of the surrounding cooled air (indoor side) becomes smaller (the boiling point of the refrigerant is between the temperature T1 outside the room and the temperature T2 inside the room), and the cooling capacity becomes smaller. .

However, since the height difference ()f) of the refrigerant liquid level is large, the refrigerant circulation capacity becomes large. Therefore, the cooling capacity tends to be difficult to reach its upper limit. The cooling capacity curve in this case is the fifth
This is shown by the solid line in (A) of the figure.

Furthermore, for example, as shown in FIG. 4, the temperature outside the room T1
If the temperature difference ΔT between the temperature T2 and the temperature T2 on the indoor side is small,
In the controller 14, the amount of refrigerant to be circulated is calculated so as to increase the efficiency of the cooling capacity with respect to the temperature difference ΔT. In this case, the amount of circulating refrigerant is calculated to be small. Then, in response to a command from the controller 14, the actuator 11 operates downward, and the refrigerant storage container 1o
The amount of refrigerant stored in the Therefore, the amount of refrigerant circulating in the liquid side refrigerant pipe 7 is reduced, and the liquid level of the refrigerant is in a low state. Therefore, the difference in height of the refrigerant liquid level becomes small and becomes h.

Therefore, the refrigerant pressure in the evaporator 1 becomes low, and the evaporation temperature of the refrigerant becomes low. As a result, the evaporation temperature and evaporator 1
The difference from the temperature T2 of the surrounding air to be cooled (indoor side) increases, and the cooling capacity increases. However, since the difference in height of the refrigerant liquid level is small (h), the refrigerant circulation ability becomes small. Therefore, the cooling capacity tends to reach its upper limit. The cooling capacity curve in this case is shown by the solid line in FIG. 5(B).

As described above, when the temperature difference ΔT changes, when the temperature difference ΔT is large, the amount of circulating refrigerant is large, and the cooling capacity shown by the solid line in (A) is ensured.

On the other hand, when the temperature difference ΔT is small, the amount of circulating refrigerant is small, and the cooling capacity shown by the solid line in (B) is ensured. In the above explanation, curves (A) and (B) of the cooling capacity against the temperature difference ΔT were shown depending on the size of the temperature difference ΔT.
When T is divided steplessly, the amount of circulating refrigerant is optimally controlled, and the cooling capacity at which the temperature difference ΔT changes is shown by the dotted line in (C). That is, in accordance with changes in the temperature difference ΔT, the optimal amount of circulating refrigerant is secured for the temperature difference ΔT, and based on this, the height difference of the refrigerant liquid level is optimally controlled, and the cooling capacity is adjusted for the temperature difference ΔT. The efficiency can be increased, and therefore, even if the temperature difference ΔT changes greatly, the efficiency of the cooling capacity can be improved over a wide temperature range.

In this embodiment, the optimal amount of circulating refrigerant for the temperature difference ΔT is determined in accordance with the change in the temperature difference ΔT, but in addition to such control,
As shown in FIG. 5, the temperature difference ΔT is a predetermined temperature difference ΔT0.
When the temperature difference ΔT is smaller than the predetermined temperature difference ΔT0, the cooling capacity can be the cooling capacity shown by the solid line (A), or the cooling capacity shown by the solid line CB) when the temperature difference ΔT is smaller than the predetermined temperature difference ΔT0.

In addition, in this embodiment, the refrigerant filling amount control means 8 is
It is composed of a refrigerant storage container 10 that communicates with the liquid side refrigerant pipe 7 via a communication pipe 9, and an actuator I, and is designed to automatically operate the reactor 11 according to commands from the controller 14. This is not limited to such a case, but it is applicable if the amount of circulating refrigerant is varied according to the temperature difference between the temperature outside the room and the temperature inside the room so as to increase the efficiency of the cooling capacity against the temperature difference between the outside temperature and the inside temperature. It can be replaced. For example, the actuator 11 in this embodiment. Outdoor temperature sensor 12. Indoor temperature detector 13
．． It is also possible to adjust the amount of refrigerant in the refrigerant storage container 10 by incorporating a screw-type reciprocating rod into the ventral refrigerant pipe 7 and manually moving it up and down according to the temperature difference without employing the controller 14.

[Effects of the Invention] As described above, according to the refrigerant natural circulation type heat transfer device according to the present invention, when the temperature difference indoors (at night) changes, the refrigerant charge amount control means The amount of refrigerant that circulates is controlled to increase the efficiency of the cooling capacity for a given temperature difference, and based on this, the difference in height of the refrigerant liquid level is controlled, making it possible to increase the efficiency of the cooling capacity for a given temperature difference. Therefore, even if the temperature difference changes greatly, the efficiency of the cooling capacity can be improved over a wide temperature range.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a natural refrigerant circulation type heat transfer device according to an embodiment of the present invention. FIG. 2 is an explanatory cross-sectional view of the refrigerant charge amount control means. FIG. 3 is an explanatory diagram of the state in which the refrigerant natural circulation type heat transfer device is used when there is a large temperature difference between indoor and outdoor temperatures. FIG. 4 is an explanatory diagram of the usage state of the refrigerant natural circulation type heat transfer device when the temperature difference between indoor and outdoor is small. FIG. 5 is an explanatory diagram of the effect of the refrigerant natural circulation type heat transfer device. FIG. 6 is a configuration diagram of a conventional refrigerant natural circulation type heat transfer device. FIG. 7 is an explanatory diagram of the effect of the refrigerant natural circulation type heat transfer device. [Explanation of symbols of main parts] 1...Evaporator IA...Inlet 1B...Outlet 3...Condenser 3A...Inlet 3 B...Outlet 6...Gas side refrigerant piping 7... Ventral refrigerant piping 8... Refrigerant filling amount control means 10... Refrigerant storage container 11... Actuator. s3 diagram Figure 4 Figure 5tm Procedural amendment form) July 4, 1988 Director General of the Japan Patent Office Yoshi 1) Tsuyoshi Moon Patent Application No. 80042 of 1988 2, Name of invention Refrigerant natural circulation heat transfer device 3 , Relationship to the case of the person making the amendment Applicant address: 4-1 Yurakucho-chome, Chiyoda-ku, Tokyo Name (183) Sanki Kogyo Co., Ltd. 4, Agent 1519 (03) 375-1631 Address: Tokyo, Japan 6th floor, 6th floor, Yui Building, 2-11-2 Yoyogi, Shibuya-ku, All drawings subject to correction 7, Details of correction

Claims (1)

[Claims] (1) An evaporator installed on the indoor side, a condenser installed on the outdoor side and located at a high place of the evaporator, and a gas side refrigerant pipe connecting the outlet of the evaporator and the inlet of the condenser. , a refrigerant natural circulation type that is equipped with a liquid side refrigerant pipe that connects the outlet of the condenser and the inlet of the evaporator, and moves heat from the indoor side to the outdoor side due to the temperature difference between the outdoor temperature and the indoor temperature. In a heat transfer device, the amount of refrigerant that circulates in the middle of the liquid side refrigerant piping is variable according to the temperature difference in order to increase the efficiency of the cooling capacity against the temperature difference between the outdoor temperature and the indoor temperature. 1. A refrigerant natural circulation type heat transfer device, characterized in that a refrigerant natural circulation type heat transfer device is provided with a refrigerant charge amount control means.