JP2011137630A - Cooling method of structure, cooling device, and structure including the cooling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling method capable of successfully forming a thin film-shaped water screen in a cooled region to which hydrophilicity imparting treatment is applied, and of suppressing water amount used during cooling, a cooling device and a structure including the cooling device. <P>SOLUTION: By applying hydrophilicity imparting treatment to the cooled region 52 on the outer surface of the structure 50, a hydrophilic layer capable of holding the water screen 60 is formed over the entire cooled region 52. By alternately performing discharge of cooling water and stop of the discharge of the cooling water with respect to the cooled region 52 having the hydrophilic layer formed thereon, repeatedly, the thin film-shaped water screen 60 is formed all the time in the entire cooled region 52, and by latent heat accompanying evaporation in the water screen 60, the structure 50 is cooled. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention forms a hydrophilic layer on the cooled region on the outer surface of the structure, supplies cooling water to the cooled region, and constantly forms a thin water film across the cooled region. The present invention relates to a structure cooling method, a cooling device, and a structure provided with the cooling device, wherein the structure is cooled by latent heat accompanying evaporation in the water film.

  In urban areas where there are many concrete buildings, the roofs and walls of the buildings are heated by direct sunlight and multiple reflections of high-rise buildings. Since the heat accumulated in the daytime in the building in this way is released to the outside air at night, the outside air temperature does not decrease even at night, causing a vicious circle in which the next day is reached with the outside air temperature rising. In addition, in a building heated in the daytime, heat is transferred to the room and the room becomes hot. Therefore, if the indoor temperature is kept comfortable, the cooling equipment is excessively used, and the amount of heat exhausted from the cooling equipment to the outside air increases, resulting in an increase in the outside air temperature. These rises in outside air temperature contribute to the so-called heat island phenomenon that causes a temperature difference between urban areas and suburbs.

  On the other hand, in the solar power generation system installed on the roof of a building, there is a problem that the power generation efficiency is lowered when the solar cell is in a high temperature state.

  In view of this, various apparatuses and methods have been proposed to cool buildings and solar cells by spraying water on the roofs, walls, and solar cells of buildings (for example, Patent Document 1).

  The photovoltaic power generation system described in Patent Document 1 includes a tile power generation unit embedded in a roof tile, water sprinkling means for spraying water on the roof surface, a temperature sensor that detects the temperature of the roof tile surface, and a temperature from the temperature sensor. A watering control unit that sprays water with watering means when the temperature exceeds a predetermined temperature. In this solar power generation system, since the tile power generation unit can be cooled by watering, a decrease in power generation efficiency can be suppressed.

  By the way, in this solar power generation system, cooling mainly using sensible heat of water is performed. This sensible heat cooling is a cooling method in which low-temperature water comes into contact with the member to be cooled and heat is transferred and cooled, and the water does not cause a phase change. In sensible heat cooling, only a cooling effect equivalent to 1 cal / g, which is the specific heat of water, can be expected. Therefore, a large amount of water is used to cool the member to be cooled by sensible heat cooling.

  As a cooling method more efficient than this sensible heat cooling, there is latent heat cooling. This latent heat cooling uses a phase change of water such as evaporation, and cools by taking away the surrounding heat by latent heat of evaporation when water evaporates, and has a cooling effect of about 540 to 580 cal / g. I can expect. In order to perform such latent heat cooling, it is effective to form a thin water film on the surface of the member to be cooled in a substantially uniform state, and the film thickness is preferably 200 μm or less. However, only by spraying water as in the solar power generation system having the above-described configuration, a thin water film is not formed on the surface of the tile power generation unit, so that latent heat cooling cannot be performed.

  Therefore, Patent Document 2 proposes a cooling method in which a thin water film is formed by supplying water to a cooled region that has been subjected to a hydrophilic treatment, and the cooled region is cooled by latent heat cooling. In this cooling method, a hydrophilic layer is formed on the surface of the roof or wall surface, water is sprayed on the surface of the hydrophilic layer to form a water film, and the roof or wall surface is cooled by latent heat accompanying evaporation in the water film. It is a method of doing. Since this cooling method is based on latent heat cooling, a high cooling effect can be expected as described above, and as a result, the amount of water used can be suppressed compared to sensible heat cooling.

  However, although it is essential to form a thin water film on the surface of the hydrophilic layer in order to perform latent heat cooling, Patent Document 2 does not describe any specific method. For example, the watering mechanism described in Patent Document 2 has a structure in which a plurality of watering nozzles protrude from a horizontal water pipe, and when water continuously flows down from such a watering nozzle, the water is simply hydrophilic. The surface of the layer simply flows down in the form of a plurality of lines, and no water film is formed. In addition, when the flow rate from the watering nozzle is increased in order to form a water film, streaky water joins together at the hydrophilic layer surface to form a water film, but the hydrophilic layer surface is increased by increasing the water flow rate. The water film thus formed is too thick to perform latent heat cooling, and eventually, it becomes difficult to obtain a high cooling effect using latent heat cooling, and the amount of water used is increased.

  In addition, in the watering mechanism having such a configuration, not only does the appearance of the protruding watering nozzle not look good, but the protruding watering nozzle creates a shadow on the surface of the hydrophilic layer, and water does not evaporate in that portion. There was a problem.

  Therefore, Patent Document 3 proposes a cooling device that can form a thin water film on the surface of the hydrophilic layer and does not have a watering nozzle.

  The cooling device includes a hose made of a porous material, a hose attachment portion for hooking the hose, a water passage member provided in the hose attachment portion, and a photocatalyst surface that has been hydrophilized with a photocatalyst. I have. Then, the water discharged from the hose is leached from the water-permeable member such as a sponge onto the photocatalyst surface, thereby forming a thin water film on the photocatalyst surface.

Noto 3075758 JP 2002-201727 A JP 2004-360292 A

  However, in the above cooling device, a porous material is used for the hose and a sponge or the like is used for the water passing member. Usually, since these items are fine in eyes, the eyes are clogged with scales or the like. There is a risk that.

  On the other hand, in order to prevent this clogging, if the eyes of the hose and the water passage member are roughened, excessive water is supplied to the photocatalyst surface, so that a thin water film is not formed.

  The present invention has been made in view of the actual situation, and the object thereof is to make it possible to satisfactorily form a thin-film water film in a cooled region that has been subjected to a hydrophilic treatment, and to use an amount of water used for cooling. The present invention provides a cooling method for a structure, a cooling device, and a structure including the cooling device.

  In order to solve the above-described problems, the cooling method for a structure according to the present invention is a hydrophilic property capable of retaining a water film over the entire area to be cooled by applying a hydrophilic treatment to the area to be cooled on the outer surface of the structure. In addition, the cooling water discharge and the cooling water discharge stop are alternately and repeatedly performed on the cooling area in which the hydrophilic layer is formed, thereby forming a thin film over the entire cooling area. A water film is always formed, and the structure is cooled by latent heat accompanying evaporation in the water film.

  According to the present invention, a hydrophilic layer is formed over the entire area to be cooled, and the cooling water discharge and the cooling water discharge stop are alternately and repeatedly performed on the cooling area. The cooling water discharged intermittently is supplied to the cooled area little by little and flows down at a moderate speed while spreading in the cooled area having hydrophilicity. Thereby, a thin film-like water film is always formed over the whole area to be cooled, latent heat cooling is stably performed, and the structure can be cooled effectively.

  Further, unlike the conventional method in which cooling water is continuously discharged to the cooled region, a small amount of cooling water is discharged intermittently, so that the amount of cooling water used can be suppressed.

  Further, it is preferable that the cooling water is discharged for 0.1 to 5 seconds and the cooling water discharge is stopped for 3 to 15 seconds in order to always form a thin water film.

  When the cooling water discharge time is less than 0.1 seconds, the amount of cooling water supplied to the cooled area is insufficient, and the cooling water does not spread over the entire area to be cooled. In addition, when the cooling water discharge time exceeds 5 seconds, the amount of cooling water supplied to the cooled region becomes excessive, and the water film formed in the cooled region becomes thick.

  In addition, if the cooling water discharge stop time is less than 3 seconds, the amount of cooling water discharged to the cooled region increases and the formed water film becomes thick. It becomes difficult to generate. Also, if the cooling water discharge stop time exceeds 15 seconds, the amount of cooling water supplied to the region to be cooled does not reach the amount necessary to constantly form a water film. Water may flow down from the cooled region, and the water film may be partially interrupted in the cooled region. However, when the lower limit value of the cooling water discharge stop time is 3 seconds, the amount of cooling water discharged becomes an appropriate amount, and a water film is favorably formed in a thin film shape in the cooled region. Further, when the upper limit value of the cooling water discharge stop time is 15 seconds, it is possible to secure a supply amount necessary for constantly forming the water film, and to form the water film well over the entire area to be cooled. be able to.

  The water film preferably has a thickness of 10 to 100 μm at its thinnest portion.

  If the film thickness of the thinnest part of the water film is less than 10 μm, the water film is partially interrupted, and if it exceeds 100 μm, the water film has a thickness that is not suitable for latent heat cooling over the entire area to be cooled. Thus, it is not difficult to obtain a desired cooling effect.

  The cooling water is discharged from a plurality of discharge ports having a diameter of 0.3 to 1.5 mm arranged at intervals of 10 to 50 mm along the width direction at the upstream end of the cooled region. preferable.

  When the diameter of the discharge port is less than 0.3 mm, it is necessary to increase the discharge pressure at each discharge port in order to secure the discharge amount necessary for forming the water film. In order to realize this high discharge pressure, it is necessary to increase the supply pressure of the cooling water to the discharge port, which requires an expensive pump that can be set to a high supply pressure. There is a problem that the equipment cost increases. In addition, if the diameter of the discharge port exceeds 1.5 mm, the discharge pressure at each discharge port becomes non-uniform, and the amount of cooling water discharged varies depending on the position of the discharge port, and is uniform in the area to be cooled. A water film may not be formed. However, if the lower limit value of the diameter of the discharge port is 0.3 mm, it is not necessary to make the supply pressure as high as described above, and the equipment cost can be suppressed, and the discharge port is too small and the discharge port is caused by dirt or the like. There will be no blockage in a short time. Further, if the upper limit value of the diameter of the discharge port is 1.5 mm, the discharge pressure at each discharge port is almost constant, so the discharge amount of cooling water is constant at any discharge port and is uniform in the region to be cooled. A water film can be formed.

  Further, when the diameter of the discharge port is in the range of 0.3 to 1.5 mm, if the interval between the discharge ports is less than 10 mm, the discharge pressure at each discharge port becomes non-uniform, and the difference in the position of the discharge port The discharge amount of the cooling water may be different, and a uniform water film may not be formed in the cooled region. When the diameter of the discharge port is in the range of 0.3 to 1.5 mm, if the interval between the discharge ports exceeds 50 mm, the cooling water discharged to the region to be cooled cannot be spread sideways, It becomes difficult to form a film. In particular, the cooling water discharged from the adjacent discharge ports cannot be merged above the region to be cooled, and the water film is interrupted. However, if the lower limit value of the interval between the discharge ports is 10 mm, the discharge amount of the cooling water is constant at any discharge port, and a uniform water film can be formed in the cooled region. Further, when the upper limit value of the interval between the discharge ports is 50 mm, the cooling water discharged from the adjacent discharge ports can be merged even above the cooled region, and a water film is formed well in the cooled region. Is done.

  Moreover, it is preferable that the average discharge amount of the cooling water for 1 minute per 1 m width is 0.01 to 1.00 L (liter) in the cooled region.

  When the average discharge amount of the cooling water is less than 0.01 L, the water film becomes thin over the entire area to be cooled and is partially interrupted. Further, if the average amount of cooling water discharged exceeds 1.00 L, the amount of cooling water supplied to the region to be cooled becomes excessive, and it becomes difficult to form a water film in the region to be cooled.

  Further, the cooling device for a structure according to the present invention forms a hydrophilic layer capable of holding a water film over the entire area to be cooled by applying a hydrophilic treatment to the area to be cooled on the outer surface of the structure. By alternately repeating cooling water discharge and cooling water discharge stop to the cooled region, a thin water film is always formed over the entire cooled region, and evaporation in this water film is performed. A cooling device that cools the structure by latent heat accompanying the cooling water, having a plurality of cooling water discharge ports arranged at predetermined intervals, and extending in the width direction at the upstream end of the cooled region. Cooling water discharge means, cooling water supply means for supplying cooling water to the cooling water discharge means, supply amount of cooling water by the cooling water supply means, discharge time of cooling water, and cooling water And a control means for controlling the discharge stop time.

  The cooling water discharge time may be set to 0.1 to 5 seconds by the control means, and the cooling water discharge stop time may be set to 3 to 15 seconds.

  The control means is connected to a film thickness measuring means for measuring the film thickness of the water film formed in the cooled area, and is formed over the entire cooled area based on the measurement value by the film thickness measuring means. The cooling water supply means may be controlled by the control means so that the film thickness of the thinnest portion of the water film is 10 to 100 μm.

  In this case, since the film thickness measuring unit is connected to the control unit, the film thickness of the thinnest portion of the water film can be controlled more accurately to 10 to 100 μm.

  Further, the diameter of the discharge ports may be 0.3 to 1.5 mm, and the interval between the discharge ports may be 10 to 50 mm.

  Moreover, even if the said cooling water supply means is controlled by the said control means so that the average discharge amount of the 1 minute cooling water per 1 m width | variety may become 0.01-1.00L in the said to-be-cooled area | region. Good.

  Moreover, the structure of this invention was equipped with the cooling device as described in any one of the said, and the said to-be-cooled area | region to which the hydrophilization process was performed in the outer surface of the said structure.

  According to the present invention, since the cooling device according to any one of the above and a region to be cooled that has been subjected to a hydrophilic treatment are provided, a thin water film is formed on the region to be cooled of the structure. It can be formed well.

  Therefore, since the entire structure can be cooled by using the latent heat accompanying evaporation of the thin water film, heat dissipation from the heated structure, which contributed to the heat island phenomenon, and cooling equipment The amount of exhaust heat can be reduced.

  The structure cooling method, the cooling device, and the structure provided with the cooling device of the present invention can form a thin film-like water film satisfactorily in a region to be cooled that has been subjected to a hydrophilic treatment, and cooling. There is an effect that the amount of water used at the time can be suppressed.

3 is a schematic diagram illustrating a structure including a cooling device according to Embodiment 1. FIG. It is the elements on larger scale which show the cooling water discharge means of the cooling device in FIG. It is a perspective view which shows the cooling water discharge means of the cooling device in FIG. It is a graph which shows a time-dependent change of the thinnest film thickness of the water film in each point of the to-be-cooled area | region of Example 3. FIG. It is a graph which shows the time-dependent change of the thinnest film thickness of the water film in each point of the to-be-cooled area | region of Example 4. FIG. 6 is a schematic diagram illustrating a structure using a cooling device in Embodiment 2. FIG. It is the elements on larger scale which show the cooling water discharge means of the cooling device in FIG. It is a perspective view which shows the cooling water discharge means of the cooling device in FIG. It is a disassembled perspective view which shows the cooling water discharge means of the cooling device in FIG.

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

[Embodiment 1]
FIG. 1 is a schematic view showing a structure provided with a cooling device in the present embodiment, FIG. 2 is a partially enlarged view showing the vicinity of a cooling water discharge means of the cooling device, and FIG. It is a perspective view which shows a cooling water discharge means.

  The structure 50 according to the present embodiment includes a cooled region 52 and the cooling device 10.

  Here, at the upper end portion of the wall surface 53 of the structure 50 shown in FIG. 1, the cooling water discharge means 20 described later can be installed at a position retracted from the wall surface 53 to the back. As shown, a gentle slope is formed on the upper surface 54 of the retracted portion of the structure 50 so that the cooling water discharged from the cooling water discharge means 20 flows toward the wall surface 53. Accordingly, it is not necessary to install the cooling water discharge means 20 in a state where the cooling water discharge means 20 protrudes from the wall surface 53 of the structure 50, the appearance of the structure 50 is not impaired by the cooling water discharge means 20, and the cooling water is supplied to the wall surface. The flow along the line 53 can be easily performed.

  The to-be-cooled region 52 is a target region to be cooled on the outer surface of the structure 50 such as a wall or a roof. The cooled region 52 is subjected to a hydrophilic treatment, and a hydrophilic layer capable of holding the water film 60 is formed over the entire cooled region 52. As a result, when cooling water is supplied to the cooled region 52, the cooling water does not become a water droplet but flows as a uniform film due to its hydrophilicity. As a result, the cooling water is not scattered by the wind, and the water film 60 is less likely to be uneven, and the cooling water evaporates evenly and efficiently when exposed to light. The object 50 can be cooled effectively.

The material used for the hydrophilization treatment is not particularly limited as long as it can form hydrophilicity with a contact angle of 10 ° or less. For example, TiO ₂ , ZnO, SrTiO ₃ , WO ₃ , Bi _{2 can be used.} In addition to photocatalysts such as O ₃ , Fe ₂ O ₃ , and SnO ₂ , highly hydrophilic materials such as porous silica (SiO ₂ ) and water glass can be used.

  Moreover, when performing the hydrophilic treatment of the to-be-cooled area | region 52 with a photocatalyst material, it does not specifically limit as a method for activating the surface of the to-be-cooled area | region 52, For example, a corona discharge process etc. are mention | raise | lifted.

  The cooling device 10 includes a cooling water discharge unit 20, a cooling water supply unit 30, and a control unit 40.

  The cooling water discharge means 20 is for discharging cooling water to the cooled region 52. As shown in FIGS. 1 and 2, the cooling water discharge means 20 is disposed across the width direction at the upstream end of the cooled region 52. As shown in FIG. And a plurality of cooling water discharge ports 21 arranged in a row.

  When the cooling water discharge means 20 is a generally used synthetic resin tube, it is preferable to use a pipe having an inner diameter in the range of 13 to 16 mm. There is no increase in water flow resistance, and there is no increase in deflection due to its own weight or heat when water is passed through the cooling water discharge means 20 because the inner diameter is too large.

  The shape of the discharge port 21 is not particularly limited, and examples thereof include a circular shape, a square shape, and a polygonal shape.

  In addition, it is preferable that the diameter of the discharge port 21 is 0.3 to 1.5 mm, and the interval between the discharge ports 21 in the cooling water discharge unit 20 is 10 to 50 mm.

  If the diameter of the discharge port 21 is less than 0.3 mm, it is necessary to increase the discharge pressure at each discharge port 21 in order to secure the discharge amount necessary to form the water film 60. And in order to implement | achieve this high discharge pressure, the supply pressure of the cooling water to the discharge outlet 21 must be raised, and for that purpose, an expensive pump etc. which can be set to a high supply pressure is required. Therefore, there is a problem that the equipment cost increases. Further, when the diameter of the discharge port 21 exceeds 1.5 mm, the discharge pressure at each discharge port 21 becomes non-uniform, and the discharge amount of the cooling water varies depending on the position of the discharge port 21. The uniform water film 60 may not be formed in the region 52. However, if the lower limit value of the diameter of the discharge port 21 is 0.3 mm, it is not necessary to make the supply pressure as high as described above, and the equipment cost can be suppressed, and the discharge port 21 is too small to discharge due to water stains or the like. The outlet 21 is not blocked in a short time. If the upper limit value of the diameter of the discharge port 21 is 1.5 mm, the discharge pressure at each discharge port 21 is substantially constant. A uniform water film can be formed in the region 52.

  Further, when the diameter of the discharge ports 21 is in the range of 0.3 to 1.5 mm, if the interval between the discharge ports 21 is less than 10 mm, the discharge pressure at each discharge port 21 becomes non-uniform and the discharge ports 21 The discharge amount of the cooling water may vary depending on the position, and the uniform water film 60 may not be formed in the cooled region 52. When the diameter of the discharge ports 21 is in the range of 0.3 to 1.5 mm, if the interval between the discharge ports 21 exceeds 50 mm, the cooling water discharged to the cooled region 52 cannot be spread laterally. In addition, the water film 60 is hardly formed. In particular, the cooling water discharged from the adjacent discharge ports 21 cannot be merged above the region to be cooled 52 and the water film 60 is interrupted. However, if the lower limit of the interval between the discharge ports 21 is 10 mm, the discharge amount of the cooling water is constant at any discharge port 21, and a uniform water film 60 can be formed in the cooled region 52. Further, when the upper limit value of the interval between the discharge ports 21 is 50 mm, the cooling water discharged from the adjacent discharge ports 21 can also merge above the cooled region 52, and a water film is formed in the cooled region 52. 60 is formed well.

  The cooling water supply means 30 is for supplying cooling water to the cooling water discharge means 20. The cooling water supply means 30 is not particularly limited. For example, as shown in FIG. 1, a water storage tank 32 for storing cooling water, a water tank 32 and the cooling water discharge means 20 are connected to each other, and a cooling water supply path is connected. The supply path 33, the pump 31 for supplying the cooling water in the water storage tank 32 to the cooling water discharge means 20, the flow meter 34 for measuring the flow rate of the cooling water in the supply path 33, and opening and closing the supply path 33 at predetermined positions. A thing provided with the electromagnetic valve 35 which performs is used.

  The control means 40 is for controlling the amount of cooling water supplied by the cooling water supply means 30, the cooling water discharge time, and the cooling water discharge stop time. The control means 40 performs control to alternately and repeatedly discharge the cooling water and stop discharging the cooling water with respect to the cooled region 52 subjected to the hydrophilic treatment.

  In addition, it is preferable that the discharge time of the cooling water is set to 0.1 to 5 seconds by the control means 40 and the discharge stop time of the cooling water is set to 3 to 15 seconds.

  If the discharge time of the cooling water is less than 0.1 seconds, the amount of cooling water supplied to the cooled area 52 is insufficient, and the cooling water does not spread over the entire area to be cooled 52. If the discharge time of the cooling water exceeds 5 seconds, the amount of cooling water supplied to the cooled region 52 becomes excessive and the water film 60 formed in the cooled region 52 becomes thick.

  Further, if the cooling water discharge stop time is less than 3 seconds, the amount of cooling water discharged to the cooled region 52 increases and the formed water film 60 becomes thick. It becomes difficult to cause the latent heat cooling due to. In addition, when the cooling water discharge stop time exceeds 15 seconds, the amount of cooling water supplied to the cooled region 52 does not reach the amount necessary to form the water film 60 at all times. The cooling water that has flowed down flows from the cooled region 52, and the water film 60 is partially interrupted in the cooled region 52. However, when the lower limit value of the cooling water discharge stop time is 3 seconds, the amount of cooling water becomes an appropriate amount, and the thin water film 60 is favorably formed in the cooled region 52. Further, when the upper limit value of the cooling water discharge stop time is 15 seconds, it is possible to secure a supply amount necessary for constantly forming the water film 60 and to satisfactorily cover the entire area to be cooled 52. Can be formed.

  The control means 40 is connected to a film thickness measuring means 41 for measuring the film thickness of the water film 60 formed in the cooled area 52, and the cooled area 52 is based on the measured value by the film thickness measuring means 41. It is preferable that the cooling water supply means 30 is controlled by the control means 40 so that the film thickness of the thinnest portion of the water film 60 formed over the entire region is 10 to 100 μm.

  In this case, since the film thickness measuring means 41 is connected to the control means 40, the control of making the film thickness of the thinnest part of the water film 60 to 10 to 100 μm can be performed more accurately.

  Further, if the thickness of the thinnest part of the water film 60 is less than 10 μm, the water film 60 is partially interrupted, and if it exceeds 100 μm, the water film 60 is subjected to latent heat cooling over the entire area to be cooled 52. Does not become an unsuitable thickness and it is difficult to obtain a desired cooling effect.

  Moreover, it is preferable that the cooling water supply means 30 is controlled by the control means 40 so that the average discharge amount of cooling water per 1 m width per 1 m in the cooled region 52 is 0.01 to 1.00 L.

  When the average discharge amount of the cooling water is less than 0.01 L, the water film 60 becomes thin over the entire area to be cooled 52 and is partially interrupted. When the average amount of cooling water discharged exceeds 1.00 L, the amount of cooling water supplied to the cooled region 52 becomes excessive, and the water film 60 is hardly formed in the cooled region 52 in a thin film shape.

  Next, the cooling method of the present embodiment will be described using an example of the structure 50 including the cooling device 10 described above.

  First, the hydrophilic region is applied to the cooled region 52 on the outer surface of the structure 50 to form a hydrophilic layer capable of holding the water film 60 over the entire cooled region 52. The hydrophilic treatment method is not particularly limited. For example, the hydrophilic treatment is performed by providing the structure 50 with an exterior member that has been subjected to hydrophilic treatment on the surface in advance by sputtering or the like. As a result, when cooling water is supplied to the cooled region 52, the cooling water does not become a water droplet but flows as a uniform film due to its hydrophilicity. As a result, the cooling water is not scattered by the wind, and the water film 60 is less likely to be uneven, and the cooling water evaporates evenly and efficiently when exposed to light. The object 50 can be cooled effectively.

  Next, the cooling water discharge and the cooling water discharge stop are alternately and repeatedly performed on the cooled region 52 in which the hydrophilic layer is formed.

  In the cooling device 10, the cooling water stored in the water storage tank 32 is sent to the cooling water discharge means 20 through the supply path 33 by the pump 31. Subsequently, the cooling water supplied to the cooling water discharge means 20 is discharged from the discharge port 21, and the discharged cooling water is moved to the cooled region 52 by a gentle inclination provided on the upper surface 54 of the retraction portion of the structure 50. And flow down.

  At that time, the opening and closing operation of the electromagnetic valve 35 installed in the supply path 33 is performed according to the cooling water discharge time and discharge stop time set in advance by the control means 40. As a result, the cooling water discharge and the cooling water discharge stop are alternately and repeatedly performed on the cooled region 52, so that the cooling water discharged in small amounts spreads in the cooled region 52 and merges with the adjacent cooling water. While flowing down, a thin water film 60 is formed.

  On the other hand, the flow rate of the cooling water is measured by the flow meter 34 installed in the supply path 33, and the film thickness of the thinnest part of the water film 60 is measured by the film thickness measuring means 41. At that time, the control means 40 controls the water supply amount of the pump 31 to be an appropriate amount from the measured flow rate and the measured film thickness.

  As described above, the thin water film 60 is always formed over the entire area to be cooled 52, and the structure 50 is cooled by the latent heat accompanying evaporation in the water film 60.

  Table 1 shows an example and a conventional example when the water film 60 is formed in the cooled region 52 using the cooling device 10 of the present embodiment.

ここで、実施例においては、被冷却領域５２に対し冷却水の吐出と冷却水の吐出停止とを交互に繰り返し行い、従来例においては、被冷却領域５２に対し冷却水の吐出を連続的に行った。また、全ての実施例において、冷却水の吐出時間は０．１〜５秒、吐出停止時間は３〜１５秒、吐出口２１の口径は０．３〜１．５ｍｍ、吐出口２１同士の間隔は１０〜５０ｍｍ、及び、被冷却領域５２における幅１ｍ当たりの１分間の冷却水の平均吐出量は０．０１〜１．００Ｌの範囲となるようにそれぞれ設定されている。また、従来例１及び２は、実施例３及び４と同じ冷却装置１０を用いており、冷却水供給手段３０による冷却水の供給量を調節して、被冷却領域５２における幅１ｍ当たりの１分間の冷却水の平均吐出量がそれぞれ異なるようにしている。

Here, in the embodiment, the cooling water discharge and the cooling water discharge stop are alternately and repeatedly performed on the cooled region 52, and in the conventional example, the cooling water discharge is continuously performed on the cooled region 52. went. In all the examples, the cooling water discharge time is 0.1 to 5 seconds, the discharge stop time is 3 to 15 seconds, the diameter of the discharge ports 21 is 0.3 to 1.5 mm, and the interval between the discharge ports 21 is Is set to be in the range of 0.01 to 1.00 L, and the average discharge amount of cooling water per minute per 1 m width in the cooled region 52 is set to be in the range of 0.01 to 1.00 L, respectively. Further, Conventional Examples 1 and 2 use the same cooling device 10 as in Examples 3 and 4, and the amount of cooling water supplied by the cooling water supply means 30 is adjusted, so that 1 per 1 m width in the cooled region 52. The average discharge amount of the cooling water per minute is made different.

  In the conventional example, since the cooling water is continuously discharged, when the amount of water discharged is small as in the conventional example 2, the cooling water flows in a plurality of streaks in the cooled region 52. . The flow of the streak-like cooling water did not merge even below the cooled region 52, and the water film 60 was not formed well over the entire cooled region 52. Further, as the amount of cooling water to be discharged is increased, the streaky cooling water flows sequentially from the lower side of the cooled region 52. However, if the amount of discharge is not increased as in Conventional Example 1, The cooling water flow did not merge above the cooled region 52. Furthermore, in Conventional Example 1, since the water film 60 is formed as thick as 160 μm even at the thinnest part, not only the latent heat cooling is not performed well, but also the amount of cooling water used is increased. I have.

  On the other hand, in all the embodiments, the cooling water discharge and the cooling water discharge stop are alternately and repeatedly performed on the cooled region 52, so that the discharged cooling water spreads in the cooled region 52. However, since the water flowed down, the water film 60 was not interrupted in the entire area to be cooled 52 and was formed well.

  4 and 5 are graphs showing changes with time of the thinnest film thickness of the water film 60 at each point of the cooled region 52 in Examples 3 and 4, respectively. 4 and 5, the thin line indicates the film thickness of the water film 60 at a position 5 cm from the bottom of the discharge port 21 in the cooled region 52, and the thick line indicates the film thickness of the water film 60 at a position of 160 cm.

  As shown in FIGS. 4 and 5, in the cooling device 10 of the present embodiment, the discharge of the cooling water and the stop of the discharge are repeated alternately, so the film thickness of the water film 60 changes with time. However, the water film 60 is not interrupted even when the cooling water is stopped from being discharged. Further, in both cases of Examples 3 and 4, since the cooling water discharge and the discharge stop are repeatedly performed alternately, the discharged cooling water flows down while spreading, and the discharge in the cooled region 52 is performed. The film thickness of the water film 60 at a position 160 cm from the bottom of the outlet 21 is kept substantially constant regardless of the passage of time, and a good water film 60 is formed.

[Embodiment 2]
FIG. 6 is a schematic view showing a structure using the cooling device in the present embodiment, and FIGS. 7 to 9 show cooling water discharge means of the cooling device, respectively.

The structure 50 according to the present embodiment includes the cooled region 52 and the cooling device 10. Note that the structure 50 according to the present embodiment is a cooling device for the cooling device 10 according to the first embodiment. Since the configuration is the same except for the water discharge means 20, the same members are denoted by the same reference numerals and the description thereof is omitted, and only the cooling water discharge means 20 which is a difference will be described.

  Here, the cooling water discharge means 20 of the cooling device 10 of the present embodiment can be used when the retracting portion as in the first embodiment cannot be formed on the wall surface 53 of the structure 50, as shown in FIG. In addition, the cooling water discharge means 20 is disposed in a state protruding from the wall surface 53.

  The cooling water discharge means 20 is for discharging cooling water to the cooled region 52. As shown in FIGS. 6 to 9, the cooling water discharge means 20 includes a sprinkling pipe 22 that ejects cooling water and a sprinkling pipe cover 23. Further, the cooling water discharge means 20 is disposed in a state of protruding from the wall surface 53 of the structure 50. However, it is preferable to reduce the protruding amount as much as possible, so that the light blocked by the cooling water discharge means 20 is reduced. As a result, the amount of shadows formed on the surface of the cooled region 52 can be reduced. Therefore, in the water film 60 formed in the to-be-cooled region 52, the area where the light hits can be increased, the region where the water film 60 can evaporate is increased, and the cooling effect of the structure 50 can be improved.

  As shown in FIGS. 6 to 9, the water sprinkling pipe 22 is made of a hollow pipe material made of synthetic resin or metal having an internal space 22 b inside, and is horizontal to the upper part of the wall surface 53 and is predetermined with the wall surface 53. It is being fixed so that it may have an interval. A plurality of spouts 22 a are formed in the sprinkling pipe 22 at predetermined intervals in the longitudinal direction of the sprinkling pipe 22 so as to communicate the internal space 22 b and the outside of the sprinkling pipe 22. Each spout 22a is formed on the wall surface 53 side and obliquely downward.

  The sprinkling tube cover 23 is, for example, a long one that is integrally molded from a synthetic resin to a predetermined length. The mounting portion 24 that is held by the sprinkling tube 22, the upper cover portion 25, and the receiving portion 26. It consists of.

  The mounting portion 24 has a cylindrical shape, and the inner diameter thereof is slightly smaller than the outer diameter of the water spray tube 22, and the opening 24 a is formed in the mounting portion 24 over the entire length in the longitudinal direction. The circumferential length of the opening 24a is set to be smaller than the entire circumferential length of the mounting portion 24 (the circumferential length of the mounting portion 24 is set to be larger than ½ of the circumferential length. Have been). Therefore, by elastically deforming the attachment portion 24 in the direction of expanding the diameter, the attachment portion 24 can be detachably fitted to and attached to the sprinkler tube 22 from the opening 24a, and will not be inadvertently detached. Moreover, a part of the sprinkling pipe 22 and each jet nozzle 22a are exposed through the opening part 24a.

  The upper cover portion 25 is provided over the entire length of the attachment portion 24, and covers the connection piece portion 25 a extending upward from the back surface of the attachment portion 24, and the attachment portion 24 and the sprinkling pipe 22. The cover piece 25b extends in the direction of the wall surface 53 from the connecting piece 25a. The front end portion of the cover piece portion 25b is in contact with the surface of the wall surface 53 so that foreign matter such as dust is not mixed between the mounting portion 24 and the wall surface 53 from above.

  The receiving portion 26 is provided below the attachment portion 24. The receiving portion 26 includes a guide piece portion 26a that extends obliquely downward from the mounting portion 24 so as to be positioned below the jet port 22a. The distal end portion of the guide piece 26a is pressed against the wall surface 53, and the shape of the contact portion is formed to be uneven. By abutting the abutting portion with the wall surface 53, a plurality of cooling water discharge ports 21 are formed along the wall surface 53 in the longitudinal direction of the cooling water discharging means 20. The shape of the discharge port 21 is not particularly limited, and examples thereof include a circular shape, a square shape, and a polygonal shape.

  In addition, it is preferable that the diameter of the discharge port 21 is 0.3 to 1.5 mm, and the interval between the discharge ports 21 in the cooling water discharge unit 20 is 10 to 50 mm.

  When the diameter of the discharge port is less than 0.3 mm, it is necessary to increase the discharge pressure at each discharge port in order to secure the discharge amount necessary for forming the water film. In order to realize this high discharge pressure, it is necessary to increase the supply pressure of the cooling water to the discharge port, which requires an expensive pump that can be set to a high supply pressure. There is a problem that the equipment cost increases. In addition, if the diameter of the discharge port exceeds 1.5 mm, the discharge pressure at each discharge port becomes non-uniform, and the amount of cooling water discharged varies depending on the position of the discharge port, and is uniform in the area to be cooled. A water film may not be formed. However, if the lower limit value of the diameter of the discharge port is 0.3 mm, it is not necessary to make the supply pressure as high as described above, and the equipment cost can be suppressed, and the discharge port is too small and the discharge port is caused by dirt, etc. There will be no blockage in a short time. Further, if the upper limit value of the diameter of the discharge port is 1.5 mm, the discharge pressure at each discharge port is almost constant, so the discharge amount of cooling water is constant at any discharge port and is uniform in the region to be cooled. A water film can be formed.

  Further, when the diameter of the discharge port is in the range of 0.3 to 1.5 mm, if the interval between the discharge ports is less than 10 mm, the discharge pressure at each discharge port becomes non-uniform, and the difference in the position of the discharge port The discharge amount of the cooling water may be different, and a uniform water film may not be formed in the cooled region. When the diameter of the discharge port is in the range of 0.3 to 1.5 mm, if the interval between the discharge ports exceeds 50 mm, the cooling water discharged to the region to be cooled cannot be spread sideways, It becomes difficult to form a film. In particular, the cooling water discharged from the adjacent discharge ports cannot be merged above the region to be cooled, and the water film is interrupted. However, if the lower limit value of the interval between the discharge ports is 10 mm, the discharge amount of the cooling water is constant at any discharge port, and a uniform water film can be formed in the cooled region. Further, when the upper limit value of the interval between the discharge ports is 50 mm, the cooling water discharged from the adjacent discharge ports can be merged even above the cooled region, and a water film is formed well in the cooled region. Is done.

DESCRIPTION OF SYMBOLS 10 Cooling device 20 Cooling water discharge means 21 Discharge port 30 Cooling water supply means 40 Control means 41 Film thickness measurement means 50 Structure 52 Cooled area 60 Water film

Claims (11)

  The area to be cooled on the outer surface of the structure is subjected to a hydrophilic treatment to form a hydrophilic layer capable of holding a water film over the entire area to be cooled, and the object to which the hydrophilic layer is formed is formed. By alternately repeating cooling water discharge and cooling water discharge stop for the cooling area, a thin water film is always formed over the entire area to be cooled, and the latent heat associated with evaporation in this water film. A structure cooling method, characterized by cooling the structure.   The cooling method for a structure according to claim 1, wherein the cooling water is discharged for 0.1 to 5 seconds, and the cooling water discharge is stopped for 3 to 15 seconds.   The method for cooling a structure according to claim 1 or 2, wherein a thickness of the thinnest portion of the water film is 10 to 100 µm.   The cooling water is discharged from a plurality of discharge ports having a diameter of 0.3 to 1.5 mm arranged at intervals of 10 to 50 mm along the width direction at the upstream end portion of the cooled region. The method for cooling a structure according to any one of claims 1 to 3.   5. The structure according to claim 1, wherein an average discharge amount of cooling water per 1 m width per minute in the region to be cooled is 0.01 to 1.00 L. 6. How to cool things. Hydrophilic treatment is performed on the cooled region on the outer surface of the structure to form a hydrophilic layer capable of holding a water film over the entire cooled region, and cooling water is discharged to the cooled region. A cooling device that continuously forms a thin water film over the entire area to be cooled by alternately and repeatedly stopping cooling water discharge, and cools the structure by latent heat accompanying evaporation in this water film. There,
A cooling water discharge means having a plurality of cooling water discharge ports arranged at predetermined intervals, and disposed in the width direction at the upstream end of the cooled region;
Cooling water supply means for supplying cooling water to the cooling water discharge means;
A cooling device for a structure, comprising: a control means for controlling a cooling water supply amount, a cooling water discharge time, and a cooling water discharge stop time by the cooling water supply means.   The discharge time of the cooling water is set to 0.1 to 5 seconds by the control means, and the discharge stop time of the cooling water is set to 3 to 15 seconds. Structure cooling system. The control means is connected to a film thickness measuring means for measuring the film thickness of the water film formed in the cooled region,
The cooling water supply means is controlled by the control means so that the thickness of the thinnest portion of the water film formed in the entire area to be cooled is 10 to 100 μm based on the measurement value by the film thickness measuring means. The structure cooling apparatus according to claim 6 or 7, wherein the structure cooling apparatus is provided.   The diameter of the discharge ports is set to 0.3 to 1.5 mm, and the interval between the discharge ports is set to 10 to 50 mm. A cooling device for the structure described.   The cooling water supply means is controlled by the control means so that an average discharge amount of cooling water per 1 m width per minute in the cooled region is 0.01 to 1.00 L. The cooling device for a structure according to any one of claims 6 to 9. The cooling device according to any one of claims 6 to 10,
The structure comprising the cooled region that has been subjected to a hydrophilic treatment on the outer surface of the structure.

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