JPH11252762A - Cooling system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cool with high efficiency the inside of a tunnel such as a cable cave for laying high-voltage power cable. SOLUTION: Water supply piping 21 is installed along a high-voltage power cable 2 at the ceiling part of a cable cave 1 where the high-voltage power cable 2 is laid, and a nozzle 22 for spraying mist whose grain diameter is approx. 5 to 50 μm is fitted on the water supply piping 21 at appropriate intervals. Air flow is formed in a fixed direction inside the cable cave 1 by an air fan 13 and an exhaust fan 15. the sprayed mist is immediately vaporized and removes surrounding heat. The hot atmosphere generated at that time is carried by the air flow and is exhausted to the ground.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is suitable for cooling a tunnel such as a large-scale and long-distance tunnel for laying a high-voltage power cable underground, which is called a power cable tunnel. Cooling system.

[0002]

2. Description of the Related Art High-voltage cables such as 100 to 1000 kV CV cables (crosslinked polyethylene cables) are sometimes laid underground. In such a case, a tunnel called a power cable tunnel is provided underground. The cable is supported on the cable rack by providing support shelves called a cable rack at appropriate intervals. The tunnel called the power cable tunnel has, for example, a diameter of 5 m and a length of 30 km.

[0003] However, in the case of the above-mentioned high-voltage power transmission cable, a large amount of heat is generated from the cable, so that the inside of the tunnel becomes high temperature of, for example, 45 ° C or more, which degrades the performance of the cable. Because of this, it was also a problem for maintenance workers. For this reason, the inside of this kind of power cable tunnel has been conventionally cooled by the following means.

[0004] First, a method of taking outside air into a cave and cooling it has been performed. This is the simplest method in principle. As still another method, a separate cooling pipe is piped in the cave, and cooling water or refrigerant flows through the cooling pipe,
In some cases, the cooling pipe is brought into contact with a power cable, or the cooling pipe is laid above the inside of a sinus to cool the power cable indirectly.

[0005]

However, the method of taking in outside air requires a very large amount of outside air, and requires a lot of facilities including an introduction fan for taking in air and an exhaust fan for exhausting air. In addition, these have become large due to the need to cope with large capacities, and have also consumed a lot of energy. On the other hand, indirect cooling by a cooling pipe first requires a large-capacity cooler for generating cooling water and a refrigerant. Further, the quality of the cooling water and the like flowing through the cooling pipe must be separately managed, and there is also a difficulty in maintenance.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and can easily and efficiently cool the inside of a tunnel having a heating element such as a power cable tunnel as described above. It is an object of the present invention to provide a cooling system having a lower cost than before and to solve the above problem.

[0007]

According to one aspect of the present invention, a system for cooling a tunnel having a heating element is provided at predetermined intervals along a longitudinal direction of the tunnel. A spray device for spraying water into the tunnel with a particle size of 5 to 50 μm, a water supply device for supplying water to the spray device, a blower for blowing air into the tunnel along a longitudinal direction of the tunnel, An exhaust device for exhausting the atmosphere in the tunnel downstream of the airflow in the tunnel.

According to such a cooling system, the mist of the sprayed water is vaporized by the heat of the heating element in the tunnel,
At that time, the inside of the tunnel can be cooled by the heat taken away. Further, since the particle size of the sprayed water is set at 5 to 50 μm, it can be vaporized efficiently and immediately. Furthermore, since the airflow in the fixed direction along the longitudinal direction is formed in the tunnel by the blower and the exhaust device, the heat taken can be efficiently discharged to the outside by this airflow. A simple configuration is sufficient for the equipment. Here, the installation interval of the spraying device may be appropriately set according to the size and length of the tunnel, the amount of heat from the heating element, and the like. For example, when cooling the cable passage of the high-voltage power cable, 0 is set. It can be proposed to install at intervals of 0.5 m to 10 m. Further, if the spraying device is installed above the heating element to spray, for example, the high-temperature air rising from the heating element can be quickly cooled and efficiently exhausted. Further, the tunnel referred to in the present application includes another large-scale space or a long space having a heating element therein.

In such a cooling system, a spray may be applied to the heating element in the tunnel. In this case, the water mist can be efficiently supplied around the heating element having the highest temperature, so that the cooling efficiency is further improved.

Further, if the amount of spray or the amount of air blow is controlled so that the temperature and relative humidity of the atmosphere in the tunnel are equal to or less than predetermined values, the inside of the tunnel becomes extremely wet. An atmosphere can be prevented. For example, in the case of a high-voltage power cable tunnel, 3
It can be proposed to control the temperature to be 80% or less at 7 ° C.

As the air blown by the blower, the outside air may be used as it is, but the dehumidification processing is performed on the outside air according to the environment in the tunnel and the conditions of the outside air. If the air after cooling is used or the air after cooling the outside air is used as described in claim 5, the atmosphere in the tunnel can be easily reduced to a predetermined temperature and humidity atmosphere or less. is there. Examples of the air conditioner that performs dehumidification and cooling include a direct contact type heat exchange such as a fan coil unit, a cooling tower, and an air washer.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a cooling system according to a preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 schematically shows the configuration of a cooling system according to the present embodiment. Reference numeral 1 denotes a cable passage for laying a high-voltage cable 2, and the cable passage is, for example, a power plant to a substation. And for laying the high-voltage cable 2 to the rising portion of the location where the overhead wire is laid.

The outside of the cable shaft 3 constituting the entrance of the high-voltage cable 2 of the cable passage 1 into the passage, and the outside of the cable shaft 4 constituting the exit, that is, both ends of the cable passage 1 are further provided. Shafts 11 and 12 are additionally constructed at a point closer to the outside. The shaft 11 is for blowing air into the cable tunnel 1 from a fan coil unit 14 having an air supply fan 13 as a blower. The shaft 12 is for exhausting the atmosphere in the cable tunnel 1 to the ground by an exhaust fan 14 as an exhaust device. In this case, of course, shaft 1
Ducts may be installed in the insides 1 and 12 to blow and exhaust air through the ducts. Furthermore, a ventilation fan may be installed at the entrance of the cable tunnel 1 in the underground part, and an exhaust fan may be installed at the exit of the underground part of the cable tunnel 1, and both types may be used together.

As shown in FIG. 2, a water supply pipe 21 is provided near the ceiling in the cable channel 1, and a nozzle 22 as a spray device is provided in the water supply pipe 21.
Are attached at appropriate intervals. This nozzle 22
Is designed so that water flowing in the water supply pipe 21 is formed into a mist having a particle size of about 5 to 50 μm, and is sprayed toward the high voltage cable 2 below. The water in the water supply pipe 21 is supplied by a pump 24 from a tank 23 installed near an outlet above the shaft 11. 23
a is a pump for pumping water into the tank.

The fan coil unit 14 includes a cooling coil 16, a heating coil 17, and a filter 18. After the taken-in outside air is passed through the filter 18 to be cleaned, these cooling coil 16, heating coil 17
It is used as an air conditioner for adjusting the temperature.

A temperature / humidity sensor 31 is installed near the exit of the atmosphere in the cable tunnel 1, for example, in the shaft 12, and the temperature / humidity signal at the exit of the cable tunnel 1 detected by the temperature / humidity sensor 31 is obtained. , The control device 32 on the ground
Is entered. Then, the control device 32 controls the amount of air blown by the air supply fan 13 and the amount of water sent by the pump 24 on the basis of the temperature and humidity signals at the outlet of the cable tunnel 1, and sets the temperature and humidity in the cable tunnel 1 to a predetermined value. For example, the temperature is controlled to be maintained at 70% or less at 37 ° C.

The main part of the cooling system according to the present embodiment has the above configuration.
When a mist of water having a fine particle diameter of 50 μm is sprayed, the mist is immediately vaporized by heat from the high-voltage cable 2, at which time heat is taken from the surrounding atmosphere. Further, the air is blown into the cable passage 1 from the air supply fan 13 of the fan coil unit 14 and the atmosphere in the cable passage 1 is exhausted to the ground by the exhaust fan 15. In the road 1, an airflow in a certain direction is formed from the shaft 11 to the shaft 12, as indicated by the thick arrow in FIG. Therefore, the hot atmosphere when the mist is vaporized is exhausted to the ground by this air flow without interruption. Moreover, vaporization is promoted by this air flow, and water droplets adhering to walls and the like are also quickly vaporized. Therefore, the atmosphere in the cable tunnel 1 is
Cooled efficiently. If the nozzle 22 is installed above the high-voltage cable 2, the high-temperature air rising by convection can be cooled quickly. Moreover, these evaporate quickly,
It is possible to avoid being discharged and the inside of the cable channel 1 becoming wet.

Further, since the atmosphere in the cable channel 1 is prevented from being excessively moistened by the control device 32, the adverse effect of spraying water into the cable channel 1 is prevented. .

In this embodiment, the air blown by the air supply fan 13 is supplied to the fan coil unit 1.
4, the cooling process can be performed, so that even if the temperature or humidity of the outside air is high, it can be reduced to an appropriate temperature and humidity.

In terms of equipment, the cooling system according to the present embodiment uses a water supply pipe 21 provided with a nozzle 22, a fan coil unit 14 having an air supply fan 13, an exhaust fan 15, and a pump 24. The equipment is very ordinary and easy to construct. Further, since the cooling method is different from the conventional method in which the outside air is directly taken in and cooled, the capacities of the air supply fan 13 and the exhaust fan 15 may be smaller than in the conventional case. Therefore, the initial cost and the running cost are both lower than before and the energy consumption is small.

If the cable passage 1 extends over a long distance and the air supply fan 13 at the entrance of the shaft 11 and the exhaust fan 32 at the exit of the shaft 12 alone cannot form a desired airflow,
As shown in FIG. 3, other shafts 41, 42, 43,... Are appropriately constructed in the middle of the cable tunnel 1, and, for example, on the ground portions of these shafts 41, 42, 43,. A ventilation tower 45 having an air supply fan 44 and an exhaust tower 47 having an exhaust fan 46 may be appropriately installed. Of course, the air supply fan 44 may be configured so that the air after the outside air is processed by another fan coil unit is blown into the cable tunnel 1 through the shaft 42. Furthermore, the air supply fan 44 and the exhaust fan 46 may be installed in an underground part such as the shafts 42 and 43 instead of the above-ground part.

In the above-described embodiment, the cable passage 1 in which the high-voltage cable 2 is laid is selected as the object to be cooled. However, the present invention is not limited to this. It can be applied to space and long space. For example, the present invention can be applied to an indoor stadium such as a dome stadium, a subway yard, a subway tunnel, an underground mall, and other deep underground structures.

[0023]

According to the first to fifth aspects of the present invention, it is possible to efficiently cool the inside of a tunnel having a heating element with simple equipment, low running cost and low energy consumption. In the case of claim 2, more efficient cooling can be performed. In the case of the third aspect, it is possible to prevent the atmosphere in the tunnel from becoming an excessively wet atmosphere. If an air conditioner for separately performing a dehumidifying process and a cooling process is added as in claims 4 and 5, the inside of the tunnel having the heating element can be kept at a predetermined temperature and humidity atmosphere or lower throughout the four seasons.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing a configuration of a cooling system according to an embodiment of the present invention.

2 is an axial longitudinal section of a cable channel in the cooling system of FIG. 1;

FIG. 3 is an explanatory view showing a state in which another ventilation shaft and an exhaust shaft are constructed in an intermediate portion of a cable tunnel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cable tunnel 2 High voltage cable 11 Vertical shaft (for ventilation) 12 Vertical shaft (for exhaust) 13 Air supply fan 14 Fan coil unit 15 Exhaust fan 21 Water supply pipe 22 Nozzle 24 Pump 31 Temperature / humidity sensor 32 Control device

Claims (5)

[Claims] 1. A system for cooling a tunnel having a heating element, provided at predetermined intervals along a longitudinal direction of the tunnel, and spraying water into the tunnel with a particle size of 5 to 50 μm. A water supply device for supplying water to the spray device; a blower for blowing air into the tunnel along a longitudinal direction of the tunnel; and an exhaust for exhausting an atmosphere in the tunnel downstream of the blower in the tunnel. A cooling system characterized by comprising a device. 2. The cooling system according to claim 1, wherein the spraying device is configured to spray the heating element in the tunnel. 3. The control device according to claim 1, further comprising a control device for controlling at least a spray amount or a blowing amount so that the temperature and the relative humidity of the atmosphere in the tunnel are equal to or lower than predetermined values. Cooling system. 4. The cooling device according to claim 1, further comprising an air conditioner for supplying air after performing dehumidification processing to outside air to a blower. system. 5. The air conditioner according to claim 1, further comprising an air conditioner for supplying the air after performing a cooling process to the outside air to a blower. Cooling system.