JP3149740B2 - Snowmaking method and apparatus for artificial snow - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to snowmaking techniques for indoor artificial ski slopes, low-temperature experience facilities, low-temperature test facilities, and the like, and more particularly to a snowmaking method for providing a landscape similar to natural snowfall conditions.

[0002]

2. Description of the Related Art As a conventional method for making artificial snow in an indoor ski resort, there has been a method described in Japanese Patent Publication No. 7-30984. FIG. 3 is a diagram showing such an example. In FIG. 3, reference numeral 11 denotes a cool air outlet, 12 denotes a two-fluid spray nozzle, and 13 denotes a cool air outlet. A plurality of two-fluid spray nozzles 12 are arranged along with a cool air outlet 11 on the upper part of the ceiling or the side wall, and fine water droplets generated from the two-fluid spray nozzle are cooled by cold air ejected from the cool air outlet 13 to produce snow. . The feature of this conventional technique is that, by dispersing and distributing a small-capacity two-fluid spray nozzle, small water droplets can be uniformly blown over the entirety of a snowmaking room. The point is that the heat exchange rate is improved and the required amount of cold energy is reduced as compared with the case where a single spray nozzle having a capacity is used. Further, it is also possible to arbitrarily produce ice burn, compact snow or powdery snow by changing the temperature and the diameter of a water droplet depending on the ejection ratio of water and compressed air ejected from the two-fluid spray nozzle.

[0003] Japanese Patent Application Laid-Open No. 3-236575 discloses an apparatus for sufficiently dropping artificial snow even in a large indoor space.
FIG. 4 is a diagram showing such an example. In FIG.
Is a snow trapping body, 15 is a snow generating room, 16 is a cooler, 17 is a blower,
18 is a fog generator and 19 is a beating body. This device provides a snow trap 14 made of a breathable material in a snowmaking room,
A fog generator 18 is arranged. Here, the low-temperature air below the freezing point forms an airflow, and passes through the snow trap 14. Fog generator 18
Fog is frozen by this low-temperature air, and snow traps 14
A snow layer is formed on one side of. On the surface of the snow capturing body 14 opposite to the snow layer generating surface, a beating body 19 for hitting this surface to sequentially wipe off the snow layer is provided, so that artificial snow falls.

Further, Japanese Utility Model Laid-Open No. 5-40775 discloses an apparatus for dropping artificial snow like snow, which is intended for an environmental test room such as an automobile, an experience dome in a low temperature environment, and the like. . FIG. 5 is a diagram showing such an example. In FIG. 5, reference numeral 20 denotes a cooling plate, 21 denotes a brush cooler, 22 denotes a brush, 23 denotes a pan-type humidifier, 24 denotes a blower, and 25 denotes a heater. This device is disposed in a snowmaking room and has a cooling plate 20 whose surface is cooled to a low temperature capable of forming frost, a heater 25 for making the atmosphere in the snowmaking room higher in temperature and humidity than the surface of the cooling plate, and a humidifier. A device 23, a blower 24 that circulates the high-temperature and high-humidity air created by the heater 25 and the humidifier 23 into the snow-making room, and a device (brush 22) that scrapes frost that has grown on the surface of the cooling plate. I have. As specific heating and humidifying equipment,
A pan-type humidifier 23 for heating water by a heater 25 and a pipe having a large number of micro holes for ejecting steam are shown.

[0005] In addition to the above-mentioned methods, as snowmaking methods applicable to indoor ski resorts, a method of crushing and dispersing ice made ice, a method of making similar snow by impregnating a superabsorbent polymer, and the like. There is.

[0006]

However, the above prior art has the following problems.

The snowfall particles obtained by the method described in Japanese Patent Publication No. 7-30984 are small-sized spheres because the sprayed fine droplets are frozen. Therefore, the landscape at the time of snowfall becomes fog-like, and is different from the landscape of natural snowfall, particularly the landscape where large sections flutter and flutter.

The particle size of snowfall particles obtained by the apparatus disclosed in Japanese Patent Application Laid-Open No. 3-236575 is determined by collecting water droplets sprayed from a spray nozzle or ice particles in which the water droplets are frozen on a capturing body before spraying. Therefore, it is larger than the method described in Japanese Patent Publication No. 7-30984. However, the shape of the snowfall particles is spherical or massive as in the method described in the above publication. Also, since the bulk density of the massive snow is large, the falling speed is high. Therefore, the scenery at the time of snowfall is different from the appearance of fluttering.

[0009] Like the natural snow, the frost that grows by the apparatus disclosed in Japanese Utility Model Laid-Open No. 5-40775 grows by sublimating and condensing water vapor (vapor phase growth). Thus, the resulting snowfall particles can be tree-like, giving a fluttering landscape, depending on growth conditions.
However, when artificial snowmaking is performed by vapor phase growth, there is a problem in the growth rate of snow particles. That is,
If you compare the amount of snow produced by vapor phase growth with the mass of snow that can be supplied to the same area, use a spray nozzle.
No. 7-30984, JP-A-36-23657
The number is smaller than that of the device disclosed in Japanese Patent Publication No. 5

[0010] The method of crushing and scattering the ice made from ice and the method of producing similar snow by impregnating a superabsorbent polymer are for creating a slope snow cover at an indoor artificial ski resort. It does not give a snowfall landscape similar to natural snow.

The present invention has been made in order to solve the problem of the conventional snow making method that a characteristic landscape cannot be obtained during natural snowfall, and it flies down like "flutter" similar to natural snow. It is an object of the present invention to provide a method and a device for supplying a large amount of snow applicable to an indoor artificial ski resort or the like while providing a landscape.

[0012]

The above object is achieved by the following means.

[0013] In the snow making method of artificial snow, a sprayed supercooled water droplet or ice particle is charged by applying a high piezoelectric field and then captured by a capturing body, similar to a dendritic crystal grown in the capturing body. A snowmaking method characterized by dropping natural artificial snow.

According to the above means, the capturing body on which the icing grows
By providing a pair of electrodes consisting of an electrically grounded pole and a high-voltage pole that also serves as a, the application of a high piezoelectric field excites the corona discharge. The electric field, ie, supercooled water droplets or ice particles flowing between the electrodes, is charged by corona discharge from the high voltage electrode. The electrostatic force acts on the charged supercooled water droplets or ice particles toward the ground electrode (capture body) facing the high voltage electrode. Due to this electrostatic force, the supercooled water droplets or ice particles move along the lines of electric force to the ground electrode (capture body) and are captured. In this way, the supply of supercooled water droplets or ice particles to the capturing body, that is, the growth of icing is performed along the lines of electric force, so that the icing does not clump as conventionally, It has a shape similar to dendrites.
In addition, the bulk density of icing is small. The artificial snow having a shape similar to the dendritic crystal grown in this manner is shaken off by means of vibration, blowing or the like, or separated from the capturing body by means such as reversal of the electrode polarity or heating of the capturing electrode,
It provides a landscape similar to the natural snowfall that flutters down.

[0015] Further, in the above-described snowmaking method for artificial snow, the problem is solved by a snowmaking method characterized in that a projection is provided on the capturing body. In this case, if the capturing body has a projection, the lines of electric force concentrate on the projection, so that the charged supercooled water droplets or ice particles are concentrated and captured on the projection. As a result, the growth rate of icing increases.

Further, in each of the above-mentioned snow making methods for artificial snow, the applied voltage and the electrode interval are set so that the potential gradient between the electrodes becomes 100 to 500 KV / m. The problem is solved. In this case, by setting the applied voltage and the electrode interval so that the potential gradient between the electrodes is 100 to 500 KV / m, it is possible to stably obtain artificial snow having a shape similar to a dendritic crystal. it can. 100KV
If it is less than 500 mV / m, the required corona discharge will not be excited, and if it exceeds 500 KV / m, icing will be scattered during growth due to excessive electrostatic force.

Also, in a snowmaking apparatus for artificial snow, a supercooled water droplet or ice particle spraying device, a high voltage power supply and an electrode for charging the sprayed supercooled water droplet or ice particle, a charged supercooled water droplet or ice The problem is also solved by an artificial snowmaking apparatus, comprising: a trapping body for trapping particles; and means for dropping artificial snow similar to dendrites grown on the trapping body.

[0018]

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of the present invention.
In FIG. 1, reference numeral 1 denotes a high-voltage electrode, 2 denotes a ground electrode on which icing grows, and A denotes the direction in which supercooled water droplets or ice particles flow. In the present embodiment, stainless steel thin wires having a diameter of 0.2 mm are used in parallel at intervals of 10 mm as the high-voltage electrode 1, and the ground electrode 2, which also serves as a icing trap, is made of a square stainless steel having a side of 1 m. Wire mesh (gap 1
Side: 12.5 mm). Water droplets or ice particles are supplied using an ultrasonic humidifier.

In FIG. 1, a high voltage electrode 1 and a ground electrode 2
Constitutes an electrode for charging supercooled water droplets or ice particles. A high voltage is applied to the high voltage electrode 1 to charge supercooled water droplets or ice particles by corona discharge.
The ground electrode 2 is electrically grounded and also serves as a capturing body for growing icing. The supercooled water droplets or ice particles charged by the corona discharge move along the line of electric force between the electrodes due to the electrostatic force, and are captured by the ground electrode 2.

Temperature -15 ° C, spray water volume by ultrasonic humidifier
30g / min, voltage 25KV applied to pressure electrode 1, pressure electrode 1
In the example in which the distance between the ground electrode 2 and the ground electrode 2 was 90 mm, dendritic icing having a length of about 20 mm was obtained on the capturing body (ground electrode 2) in 10 minutes. The total mass of icing was about 60 g.

From these results, it is possible to supply snow having a snowfall intensity of 2 kg / m ² · h to a floor area of 1 m ² per hour by installing a snow-making facility satisfying the conditions of this embodiment on the ceiling. This snowmaking amount can be applied to leisure facilities and the like.

FIG. 2 is a diagram showing an embodiment different from FIG. 1 according to the present invention. In FIG. 2, the same portions as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. Compared with the embodiment of FIG. 1, the arrangement of the wire mesh of the ground electrode 2 also serving as a capturing body is arranged in parallel with the direction A in which the supercooled water droplets or ice particles flow. The pressing electrode 1 has a linear shape in this case. According to such an arrangement of the capturing bodies, since the lines of electric force concentrate on the projections of the wire at the end of each wire netting, individual dendritic icing grows greatly.

The supply of supercooled water droplets or ice particles does not necessarily need to be performed by the ultrasonic humidifier shown in the description section of FIG. 1 and FIG.
A two-fluid nozzle or the like may be used. 260cc with 2-fluid nozzle at -15 ℃ with the same electrode arrangement as Fig.2
When spraying was performed at a rate of / min, 300 g of dendritic icing was obtained in about 10 minutes on the electrode about 2.5 m away from the nozzle.

The amount of icing increases as the potential gradient (voltage / electrode interval) increases. However, an excessive potential gradient is not preferable because the spark discharge is excited and icing is scattered during growth due to excessive electrostatic force. According to a test using a potential gradient as a parameter, a preferable potential gradient is 500K.
V / m or less.

[0026]

As described above, according to the present invention, a supercooled water droplet or ice particle is charged by applying a high piezoelectric field to the supercooled water droplet or ice particle, and then is captured by the capturing body. Artificial snow similar to dendrites grows in the trapping body. Since this artificial snow falls, there is an effect of providing a method and apparatus for supplying a large amount of snow applicable to indoor artificial ski slopes and the like while giving a landscape that flies down like “flutter” similar to natural snow. .

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing an embodiment different from FIG. 1 according to the present invention.

FIG. 3 is a diagram showing an example of the related art.

FIG. 4 is a diagram showing an example different from FIG. 3 of the related art.

FIG. 5 is a diagram showing an example different from FIGS. 3 and 4 of the related art.

[Explanation of symbols]

 1 High voltage electrode 2 Ground electrode

──────────────────────────────────────────────────の Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F25C 3/04

Claims (4)

(57) [Claims] In a method for making artificial snow, a super-electrically sprayed supercooled water droplet or ice particle is charged by applying a high piezoelectric field and then captured by a capturing body. A snowmaking method characterized by falling. 2. The snow making method according to claim 1, wherein the capturing body has a projection. 3. The method according to claim 1, wherein the potential gradient between the electrodes is 100 to 50.
A snowmaking method characterized by setting an applied voltage and an electrode interval so as to be 0 KV / m. 4. A snowmaking apparatus for artificial snow, comprising: a device for spraying supercooled water droplets or ice particles; a high voltage power supply and an electrode for charging the sprayed supercooled water droplets or ice particles; and a charged supercooled water droplet or ice. A snowmaking apparatus for artificial snow, comprising: a capturing body for capturing particles; and means for dropping artificial snow similar to dendrites grown on the capturing body.