Tunnel cooling system

Abstract

A tunnel cooling system using vortex tubes comprises an air compression device at least partially arranged outside a tunnel, a water chilling unit, an inlet pipeline at least partially arranged inside the tunnel, a vortex tube set and a hot end outlet pipeline, and compressed air prepared by the air compression device can be cooled through the water chilling unit. The vortex tube group is formed by connecting a plurality of vortex tubes in parallel, each vortex tube comprises a vortex tube inlet, a cold end tube and a hot end tube, the inlet pipeline is connected with the vortex tube inlet, the hot end tube is connected with the hot end outlet pipeline, fluid flowing out of the cold end tube is directly discharged into the tunnel, and fluid flowing out of the hot end tube flows out of the tunnel through the hot end outlet pipeline. As no complex moving part exists in the tunnel, the tunnel is not damaged due to the influence of high ground temperature, and good system stability is achieved; and a direct refrigeration mode is adopted, the occupied space of the system in the tunnel is small, and meanwhile the fresh air problem can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of refrigeration systems, and in particular to a cooling system applied to a tunnel. Background Art

[0002] my country has a complex topography, with a three-level distribution from east to west. The western region is located in the first level, with an altitude generally higher than 3,000 meters. Tunnel excavation in the western region usually encounters adverse geological conditions such as high ground temperature, and the heat damage caused by high ground temperature is particularly serious, which will not only cause physical harm to construction workers, but also cause irreversible damage to excavation machinery, increase its failure rate, reduce work efficiency, and may deteriorate the performance of the tunnel structure and reduce its durability.

[0003] In order to solve the problem of heat damage caused by high ground temperature during tunnel construction, steam compression refrigeration systems are currently used. However, due to the large space of the tunnel and the fact that it is an open space, the energy consumption of the compression refrigeration system is too high, and the compressor has a very high failure rate due to the influence of the high ground temperature. In addition, in order to provide cooling capacity, the steam compression refrigeration system requires the use of fan coil units, etc. for heat exchange, which often occupies a large space inside the tunnel construction. Summary of the invention

[0004] The object of the present invention is to provide a tunnel cooling system which will not be affected by high ground temperature during tunnel construction and has high system stability.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions.

[0006] A tunnel cooling system, characterized in that it is applied to a tunnel, comprises an air compressor, a chiller, an inlet pipe, a vortex tube group, and a hot end outlet pipe, wherein the air compressor is used to prepare compressed air, the air compressor is connected to the chiller, the chiller is connected to the inlet pipe, the compressed air prepared by the air compressor can be cooled by the chiller, the air compressor and the chiller are at least partially located outside the tunnel; the inlet pipe is at least partially located inside the tunnel, the vortex tube group is formed by connecting a plurality of vortex tubes in parallel, the vortex tube comprises a vortex tube inlet, a cold end tube, and a hot end tube, the inlet pipe is connected to the vortex tube inlet, the hot end tube is connected to the hot end outlet pipe, the vortex tube can separate the energy of the compressed air flowing into the vortex tube inlet and flow out two fluids from the cold end tube and the hot end tube, the temperature of the fluid flowing out of the cold end tube is lower than the temperature of the vortex tube inlet, the fluid flowing out of the cold end tube is directly discharged into the tunnel, and the fluid flowing out of the hot end tube flows out of the tunnel through the hot end outlet pipe. In this way, since the vortex tube group, inlet pipe, and hot end outlet pipe do not have complex moving parts, they will not be damaged by the high ground temperature and have good system stability. In addition, the applicant found during the research that during the tunnel construction process, the environment as a whole will have a large demand for fresh air, but because the fresh air system often takes up a large space and affects the construction space, it cannot be set up. The technical solution of the present invention can effectively reduce the size of the air duct because the air compression device greatly increases the air density. At the same time, the fluid flowing out of the cold end is directly used as fresh air, which improves the environment in the tunnel construction space. In addition, there is no need to set up heat exchange devices such as fan coil units, the structure is relatively simple, and it occupies a small construction space.

[0007] Further, the inlet pipeline includes a tunnel pipeline and a distribution pipeline, the tunnel pipeline is arranged along the extension direction of the tunnel, the distribution pipeline is arranged along the outer periphery of the tunnel, the distribution pipeline is provided with a vortex tube interface, the vortex tube interface is connected to the vortex tube inlet, and the gas in the tunnel pipeline enters the vortex tube after passing through the distribution pipeline; the hot end outlet pipeline includes a tunnel outlet pipeline and a collecting pipeline, the tunnel outlet pipeline is arranged along the extension direction of the tunnel, the collecting pipeline is arranged along the outer periphery of the tunnel, the collecting pipeline is provided with a vortex tube hot end interface, the vortex tube hot end interface is connected to the hot end pipe, and the fluid flowing out of the hot end pipe enters the tunnel outlet pipeline after passing through the collecting pipeline.

[0008] Furthermore, the tunnel pipeline adopts a segmented detachable structure, and the plurality of distribution pipelines are sequentially arranged along the tunnel pipeline direction, and the tunnel outlet pipeline adopts a segmented detachable structure, and the plurality of collecting pipelines are sequentially arranged along the tunnel outlet pipeline direction. With the detachable structure, the tunnel pipeline can be extended as the tunnel construction depth increases, and the distribution pipeline can be increased or adjusted, so that the tunnel cooling system can adapt to the tunnel processing progress and enhance flexibility.

[0009] Furthermore, the distance between adjacent distribution pipes is no greater than 20 meters; the distance between adjacent collection pipes is no greater than 20 meters. According to the applicant's research, controlling this distance can achieve a relatively ideal cooling effect.

[0010] Furthermore, a plurality of vortex tubes are evenly arranged on each distribution pipeline, and the cold end outlets of the vortex tubes face the center of the tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a partial schematic diagram of an implementation method of a tunnel cooling system of the present invention.

[0012] Figure 2 It is a partial schematic diagram of an implementation method of a tunnel cooling system of the present invention. DETAILED DESCRIPTION

[0013] Figure 1-Figure 2 The diagram shows a tunnel cooling system, including an air compression device 100, a chiller 200, an inlet pipe 300, a hot end outlet pipe 400, and a vortex tube group 500. It should be noted that the diagram is only schematically expressed and does not represent the number of actual devices.

[0014] The air compressor 100 is used to prepare compressed air. The air compressor 100 is connected to a water chiller 200, which can pre-cool the compressed air prepared by the air compressor 100 to enhance the cooling effect of the vortex tube, and can control the cooling capacity of the tunnel cooling system to a certain extent through the water chiller 200.

[0015] The chiller 200 is connected to the inlet pipe 300 .

[0016] The inlet pipe 300 is at least partially located in the tunnel. The inlet pipe 300 includes a tunnel-side pipe and a distribution pipe 310. The tunnel-side pipe is arranged along the direction of the tunnel extension, and the distribution pipe 310 is arranged along the outer periphery of the tunnel. The distribution pipe is provided with a vortex tube interface. The direction of tunnel extension refers to the direction from one entrance to another of the tunnel; the arrangement along the outer periphery of the tunnel refers to the arrangement close to the inner wall (cross section) of the tunnel, such as Figure 2 The distribution pipeline 310 and the collecting pipeline 410 are shown, both of which belong to the steps along the outer periphery of the tunnel.

[0017] The hot end outlet pipeline 400 includes an outlet pipeline along the tunnel and a collecting pipeline 410. The outlet pipeline along the tunnel is arranged along the direction of the tunnel extension, and the collecting pipeline 410 is arranged along the outer periphery of the tunnel. The collecting pipeline is provided with a vortex tube hot end interface.

[0018] The vortex tube group 500 is formed by connecting multiple vortex tubes in parallel. The vortex tube includes a vortex tube inlet 510, a hot end tube 520, and a cold end tube 530. The vortex tube can separate the energy of the compressed air flowing into the vortex tube inlet and flow out two streams of fluid from the two outlets of the cold end tube and the hot end tube. The temperature of the fluid flowing out of the cold end tube is lower than the temperature of the vortex tube inlet, and the temperature of the fluid flowing out of the cold end is also lower than the temperature of the fluid flowing out of the hot end tube. The vortex tube interface is connected to the vortex tube inlet, and the gas in the tunnel pipeline enters the vortex tube after passing through the distribution pipeline 310; the vortex tube hot end interface is connected to the hot end tube, and the fluid flowing out of the hot end tube enters the tunnel outlet pipeline after passing through the collecting pipeline 410. The fluid flowing out of the cold end tube is directly discharged into the tunnel.

[0019] The pipeline along the tunnel adopts a segmented detachable structure, and multiple distribution pipelines are arranged in sequence along the tunnel pipeline direction, and the distance between adjacent distribution pipelines is not more than 20 meters. The pipeline along the tunnel outlet adopts a segmented detachable structure, and multiple collection pipelines are arranged in sequence along the tunnel outlet pipeline direction, and the distance between adjacent collection pipelines is not more than 20 meters.

[0020] Multiple vortex tubes are evenly arranged on each distribution pipeline, and the cold end outlet of the vortex tube faces the center of the tunnel.

[0021] Especially when the tunnel is long (it can also be arranged in this way when the tunnel is not long), at least part of the pipeline along the tunnel is insulated; at least part of the pipeline along the tunnel outlet is insulated, so as to achieve the purpose of reducing the heat exchange between the gas in the pipeline along the tunnel, the gas in the pipeline along the tunnel outlet and the gas in the tunnel.

[0022] In the tunnel cooling system of this embodiment, the cooling energy is mainly generated by energy separation in the tunnel through the vortex tube group, and the cooling energy is directly discharged into the construction site. The cooling energy generated by the vortex tube energy separation is basically utilized, reducing the loss of cooling energy along the way and improving the utilization rate of cooling energy. In addition, the provision of cooling energy does not require the use of fan coil units, etc., and occupies less internal space. At the same time, the increase in tunnel construction depth can be achieved by extending the tunnel pipeline, the tunnel outlet pipeline, and adding or changing the distribution pipeline, the collection pipeline, etc., which has strong flexibility. Compared with the steam compression refrigeration system, the vortex tube group of this system is not affected by the high temperature and high humidity environment, and no complex moving parts such as compressors are set in the tunnel. It will not be affected by high ground temperature, can work continuously and uninterruptedly, and has better system stability and lower failure rate.

[0023] In addition, the cold air flowing out of the vortex tube group not only cools down the large space of the tunnel, but also promotes air circulation. As a fresh air system, it promotes air purification in the tunnel and realizes the dehumidification function to a certain extent (the temperature of the low-temperature gas at the cold end outlet is lower than the dew point temperature under the current pressure, the water vapor in the gas is supersaturated and undergoes a phase change, condensing into liquid water droplets, reducing the air humidity in the tunnel).

[0024] Working condition 1: Take the tunnel environment with a length of 3 km, a construction section of 150 m, an ambient temperature of 30°C outside the tunnel, a rock wall temperature of 80°C, and continuous heat release from the rock wall as an example. To optimize the construction environment, the ambient temperature of the construction section in the tunnel needs to be reduced to 25°C. The following solutions can be used:

[0025] The air compression device uses two air compressors with a total flow of 2000N·m3 / min and an outlet pressure of 850kPa high-pressure air. When working, the normal temperature and low-pressure air is compressed to a high temperature and high pressure state by the air compressor, and then enters the 800kW cooling water chiller, which can cool the high temperature and high pressure air to 7°C. The cooled high-pressure and low-temperature air is transmitted to the construction section through 5 ND300 vacuum tubes (along the tunnel pipeline), and further through the distribution pipelines arranged along the outer periphery of the tunnel wall (can be in the form of hoses), the low-temperature gas is transported to the vortex tube inlets of the vortex tube group. The vortex tube inlet temperature is 8.07°C. The resistance loss of the vacuum tube along the way is about 36.1kPa, and the vortex tube inlet pressure is about 800kPa. The adjacent distribution pipelines are spaced 10 meters apart, and 25 vortex tubes are set in each distribution pipeline. The vortex tube cold flow ratio is set to 0.63, and the cold end outlet temperature reaches -27.83°C through the vortex tube temperature separation, which cools the tunnel construction section. At the same time, the system can provide fresh air with a wind speed of 0.1711m / s in the tunnel, improving the construction environment. Table 1 is the design working condition table for working condition 1.

[0026] Table 1: Design conditions of Example 1

[0027]

[0028] Working condition 2: Take the tunnel environment with a length of 3 km, a construction section of 150 m, an ambient temperature of 30°C outside the tunnel, a temperature of 50°C inside the tunnel, a humidity of 80%, and continuous heat release from the rock wall as an example. To optimize the construction environment, the ambient temperature of the construction section in the tunnel needs to be reduced to 25°C and the humidity to 40%.

[0029] The air compression device uses two air compressors with a total flow of 1300N·m3 / min and an outlet pressure of 850kPa high-pressure air. When working, the normal temperature and low-pressure air is compressed to a high temperature and high pressure state by the air compressor, and then enters the chiller with a refrigeration capacity of 580kW, which can cool the high temperature and high pressure air to 7℃. The cooled high-pressure and low-temperature air is transmitted to the construction section through 4 ND300 vacuum pipes (along the tunnel pipeline), and the low-temperature gas is transported to the inlet of each vortex tube of the vortex tube group through the distribution pipeline arranged along the outer periphery of the tunnel wall (which can be in the form of a hose). The inlet temperature of the vortex tube is 8.18℃. The resistance loss of the vacuum tube along the way is about 42.13kPa, and the inlet pressure of the vortex tube is about 800kPa. The adjacent distribution pipelines are 15 meters apart, and each distribution pipeline is equipped with 25 vortex tubes (which can be appropriately increased or decreased according to actual needs). The vortex tube cold flow ratio is set to 0.63. Through the vortex tube temperature separation, the cold end outlet temperature reaches -27.72℃, which cools the tunnel construction section. At the same time, the cold end outlet temperature is 10.5℃ lower than the target dew point temperature, which can effectively reduce the air humidity. In addition, the system can provide fresh air with a wind speed of 0.1175m / s in the tunnel to improve the construction environment. Table 2 is the design working condition table of working condition 2.

[0030] Table 2: Design conditions of Example 2

[0031]

Claims

1. A tunnel cooling system, characterized in that: The invention is applied to a tunnel, and comprises an air compressor, a chiller, an inlet pipe, a vortex tube group, and a hot end outlet pipe. The air compressor is used to prepare compressed air. The air compressor is connected to the chiller, and the chiller is connected to the inlet pipe. The compressed air prepared by the air compressor can be cooled by the chiller. The air compressor and the chiller are at least partially located outside the tunnel; the inlet pipe is at least partially located inside the tunnel. The vortex tube group is formed by connecting a plurality of vortex tubes in parallel. The vortex tube comprises a vortex tube inlet, a cold end tube, and a hot end tube. The inlet pipe is connected to the vortex tube inlet, and the hot end tube is connected to the hot end outlet pipe. The vortex tube can separate the energy of the compressed air flowing into the vortex tube inlet and discharge two fluids from the cold end tube and the hot end tube. The temperature of the fluid flowing out of the cold end tube is lower than that of the vortex tube inlet. The fluid flowing out of the cold end tube is directly discharged into the tunnel, and the fluid flowing out of the hot end tube flows out of the tunnel through the hot end outlet pipe.

2. The tunnel cooling system according to claim 1, characterized in that: The inlet pipeline includes a tunnel pipeline and a distribution pipeline. The tunnel pipeline is arranged along the direction of extension of the tunnel, and the distribution pipeline is arranged along the outer periphery of the tunnel. The distribution pipeline is provided with a vortex tube interface, and the vortex tube interface is connected to the vortex tube inlet. The gas in the tunnel pipeline enters the vortex tube after passing through the distribution pipeline; the hot end outlet pipeline includes a tunnel outlet pipeline and a collecting pipeline. The tunnel outlet pipeline is arranged along the direction of extension of the tunnel, and the collecting pipeline is arranged along the outer periphery of the tunnel. The collecting pipeline is provided with a vortex tube hot end interface, and the vortex tube hot end interface is connected to the hot end pipe. The fluid flowing out of the hot end pipe enters the tunnel outlet pipeline after passing through the collecting pipeline.

3. The tunnel cooling system according to claim 2, characterized in that: The pipeline along the tunnel is arranged in a segmented detachable structure, and the multiple distribution pipelines are arranged in sequence along the direction of the pipeline along the tunnel. The pipeline at the tunnel outlet is arranged in a segmented detachable structure, and the multiple collecting pipelines are arranged in sequence along the direction of the tunnel outlet.

4. The tunnel cooling system according to claim 3, characterized in that: The distance between adjacent distribution pipes shall not exceed 20 meters; the distance between adjacent collecting pipes shall not exceed 20 meters.

5. The tunnel cooling system according to claim 4, characterized in that: A plurality of vortex tubes are arranged on each distribution pipeline, and the cold end tubes of the vortex tubes face the center of the tunnel.

6. The tunnel cooling system according to any one of claims 2 to 5, characterized in that: The pipeline along the tunnel is at least partially insulated; the pipeline at the tunnel outlet is at least partially insulated.

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