JP6753036B2 - How to make snowfall wet - Google Patents

Description

The present invention relates to a method for moistening snowfall, and more particularly to a method for moistening snowfall to achieve a desired moisture content in a limited enclosed snowfall space, regardless of the type of snow.

Conventionally, for example, in a snow environment test of an automobile, wet snow has been simulated by converting snowfall into wet snow.
Patent Document 1 relates to an artificial snowmaking device. The artificial snowmaking device has a snowfall chamber and a snow generation chamber in the upper part of the snowfall chamber, the lower part of which communicates with the snowfall chamber, and a part of the air in the snowfall chamber is generated as snow. A bypass air passage for supplying to the room is provided, and air is blown out from this bypass air passage toward the snowfall chamber.
According to such an artificial snowfall device, the snow generation chamber has a temperature below the freezing point for snow generation, while the snowfall chamber is kept so as not to become a temperature below the freezing point by sending an air conditioner or warm air. The updraft from the to the snow generation chamber is blocked by the air blown from the bypass air passage toward the snowfall chamber, and snow is generated without hindrance in the snow generation chamber. In the snowfall chamber, it is damp during snowfall. Snow will be formed.

Patent Document 2 relates to a snow accumulation control method for artificial snow, and the device for implementing the artificial snow accumulation control method includes a snowfall device and air that injects air from the snowfall device toward the snow that falls above the snowfall chamber. It has an injection means, and by changing the injection air volume and injection time of the air injected by this air injection means, the snow accumulation state in the snowfall room is controlled, and in particular, the air heated by the heater is injected. It is configured to spray against snow during snowfall.
According to such a device, the snow surface can be piled up so as to be substantially flat, and the surface of the snow is melted and moistened by injecting warm air onto the snow during snowfall. Snow can be reproduced.
As described above, in any of the artificial snowmaking devices, it is possible to make the artificial snow wet to some extent during the snowfall, but it has the following technical problems.

That is, conventionally, when artificial snow is made indoors and it snows, the wet snow making technology has been adopted, in which the water content of the snow is only a matter of course.
First, it is difficult to achieve the desired moisture content of wet snow in the limited enclosed snowfall space in the room.
More specifically, in any case, it is not even disclosed that the closed snowfall space is controlled to a predetermined temperature or a predetermined humidity, and in Patent Document 1, the temperature of the snowfall chamber is higher than the temperature of the snowmaking chamber. If it is only disclosed and relatively high, for example, it is impossible to achieve wet snow when the snowfall room is below freezing. In addition, if the temperature of the snowfall chamber is higher than 0 ° C, it is possible to make the snow wet to some extent, but the moisture content of the snow is natural. On the other hand, in Patent Document 2, when the snowfall space is below the freezing point, refreezing is caused and the snow does not become wet. In addition, even if the dry-bulb temperature is 0 ° C or higher, if the humidity is low and the wet-bulb temperature is 0 ° C or lower, the wet-bulb temperature becomes insufficient due to refreezing caused by the evaporation of a part of the molten water. .. Furthermore, if the mixing time (aging time) with hot air is short, the snow will not melt sufficiently.

Secondly, when the desired moisture content of snow is determined by the method of using wet snow, it is difficult to adopt an efficient and appropriate wet snowification technique according to the desired moisture content.
More specifically, in each case, controlling the closed snowfall space to a predetermined temperature and a predetermined humidity is not even disclosed, and the size of the closed snowfall space, that is, the time during which wet snow can be formed, and the desired water content of the snow are not disclosed. Depending on the rate, the temperature of the closed snowfall space should be kept within a predetermined range, the temperature and humidity of the closed snowfall space should be kept within a predetermined range, or the humidity of the closed snowfall space should be kept within a predetermined range while being sealed. Although it is possible to consider whether to generate mist in the snowfall space, such selection is difficult and efficient wet snow formation cannot be achieved.

Thirdly, it is difficult to selectively moisten the artificial snow or natural snow caused by ice particles and crystalline snow.
More specifically, in each case, artificial snow is created indoors, and while it is snowed in a closed snowfall space, it becomes wet as a matter of course. During outdoor snowfall, natural snow is targeted. It is difficult to make the snow wet, let alone artificial snow that is made indoors and natural snow that is made indoors, depending on the purpose of use.

Japanese Patent Application Laid-Open No. 2-306075 Japanese Patent Application Laid-Open No. 2008-298331

In view of the above technical problems, an object of the present invention is to provide a method for moistening snowfall that achieves a desired water content in a limited closed snowfall space regardless of the type of snow. ..

In order to achieve the above problems, the method for making snowfall wet according to the present invention is
A step of producing a mist of water droplets of a given particle size in air controlled to keep the temperature and / or humidity within a given range.
It has a step of passing snowfall through the mist, and adjusts the particle size of the mist and / or the density of water droplets in the mist according to the time during which the snowfall can become wet, and wet snow with a desired water content. It is configured to be converted.

Hereinafter, embodiments of the wet snow device 100 of the present invention will be described in detail below with reference to the drawings.
In a snowfall system used for an environmental test of an automobile, a crystal snow production section is provided in the upper part and a crystal snowfall section is provided in the lower part in a space partitioned vertically by a partition extending in the horizontal direction.

The crystalline snow production department forms crystalline snow by growing frost on the mesh-like membrane surface by supplying moist air containing water vapor above ice saturation to the mesh-like membrane surface below freezing point, and the formed crystalline snow. Is a conventionally known type in which the ice cubes are physically dropped by a scraper or the like, and detailed description thereof will be omitted.
In the crystal snowfall section, a wet snow conversion device 100 is provided in order to wet the crystal snow during the snowfall.

As shown in FIG. 1, the wet snow conversion device 100 forms a closed snowfall space 600 inside by the peripheral side surface 602 and the top surface 606 straddling the upper peripheral edge 604 of the peripheral side surface 602, and the top surface 606 has a closed snowfall space 600. A partition means 607 for snowfall in the closed snowfall space 600 while receiving snowfall from above is provided, a temperature adjusting means 612 for adjusting the temperature in the closed snowfall space 600, and a humidifying means for humidifying the inside of the closed snowfall space 600. The humidifying means 614 and the humidifying amount adjusting means 616 for adjusting the humidifying amount so as to keep the humidity in the closed snowfall space 600 within a predetermined range.

The wet snow making device is a portable type with casters 601, and it is possible to select whether to make wet snow for natural snow outdoors or for artificial snow indoors. The temperature adjusting means 612, the humidifying means 614, and the humidifying amount adjusting means 616 are carried by the casters 601.

The humidification amount adjusting means 616 adjusts the humidification amount so that the humidity in the closed snowfall space 600 is kept within a certain range by varying the amount of fine water droplets to be supplied.

As a modification, the humidification amount adjusting means 616 further has a humidity detecting means (not shown) for detecting the humidity in the closed snowfall space 600, and the closed snowfall space is based on the humidity detected by the humidity detecting means. The amount of humidification may be adjusted by varying the amount of fine water droplets supplied to the 600.
As a further modification, the humidification amount adjusting means 616 further includes a temperature detecting means (not shown) for detecting the temperature in the closed snowfall space 600, and per unit time of the temperature detected by the temperature detecting means. The amount of humidification may be adjusted by varying the amount of fine water droplets supplied to the closed snowfall space 600 based on the amount of change in.

The mist generator constituting the humidifying means 614 and the humidifying amount adjusting means 616 is provided with mist supply ports 630A, B and C constituting the mist injection nozzle on the peripheral side surface 602, and the air conditioner constituting the temperature adjusting means 612 is The air outlet 610 and the air suction port 612 are similarly provided on the peripheral side surface 602.

Regarding the formation of mist, the humidity in the closed snowfall space 600 is detected by the humidity sensor, and the amount of humidification in the humidifying means is adjusted so that the inside of the closed snowfall space 600 is within a predetermined humidity range. To adjust the amount of humidification, change the rotation speed of the circulation fan that circulates the air in the closed snowfall space 600, the opening degree of the water supply amount adjusting valve 3 that adjusts the supply amount of the humidified water used for humidification, and the temperature of the humidified water. By changing the heating amount of the water heat exchanger, the amount of fine water droplets mixed in the circulating air is changed to adjust the humidification amount.

More specifically, as shown in FIG. 1, a circulation air passage for sucking air in the closed snowfall space 600 through the intake port 620 and blowing out air through the air outlet 610, and providing ventilation to the circulation air passage. A circulation fan, a humidified water ejection nozzle that supplies water to the circulating fan, a ventilation fan that sucks the air in the closed snowfall space 600 and exhausts it outdoors through an exhaust duct, and a humidified water to be supplied to the humidified water ejection nozzle. A water heat exchanger, an electromagnetic valve that interrupts the supply of humidified water to the humidified water ejection nozzle, a water supply amount adjusting valve for adjusting the amount of humidified water ejected, and humidity that detects the humidity of the air passing through the circulation air passage. It is equipped with a sensor, a suction temperature sensor that detects the temperature of the air inside the sealed snowfall space 600 that sucks in from the intake port 620, a blowout temperature sensor that detects the temperature of the air that blows out from the outlet 610, and the like.

The humidity sensor is provided in the vicinity of the intake port 620 of the circulation air passage, and detects the humidity of the air sucked from the intake port 620. Further, the temperature of the air inside the closed snowfall space 600 and the temperature of the humidified air blown out are detected by the suction temperature sensor provided near the intake port 620 and the blowout temperature sensor provided near the outlet 610. Based on the preset suction humidity, suction temperature, and blowout temperature, the circulation air volume by the circulation fan, the supply amount of humidified water ejected from the humidifying water ejection nozzle, and the supply water temperature are determined, and the rotation speed of the circulation fan and the water supply are determined. The amount of humidification is adjusted by changing the opening degree of the amount adjusting valve and the amount of heating in the water heat exchanger. To increase the amount of humidification, increase the rotation speed of the circulation fan, open the opening of the water supply amount adjustment valve, and increase the amount of heat in the water heat exchanger to supply fine water droplets into the sealed snowfall space 600. The supply amount can be increased and the humidification amount can be increased. On the contrary, when the amount of humidification is lowered, the rotation speed of the circulation fan is lowered, the opening of the water supply amount adjusting valve is closed, and the amount of heating in the water heat exchanger is reduced to supply fine particles into the closed snowfall space 600. The amount of water droplets supplied can be reduced, and the amount of humidification can be reduced. The optimum mist state can be formed by determining the combination of the operating states of the circulation fan, water supply amount adjusting valve, and water heat exchanger based on the suction temperature and the blowout temperature detected by the suction temperature sensor and the blowout temperature sensor. It becomes.

As long as it is possible to uniformly generate mist in the entire sealed snowfall space, the method of generating mist is a conventionally known technique, for example, a method using a two-fluid nozzle that sprays water together with compressed air. For example, by applying a high-frequency AC voltage to a piezoelectric ceramic oscillator, the vibration energy of ultrasonic waves is transmitted to the water surface, and ultrasonic waves that generate fine mist are used to control the humidified water temperature with a running water type. Both a method using a humidifying pan performed by a heater and a method of directly spraying steam can be adopted.

In this case, a plurality of mist spray nozzles may be installed on the peripheral side surface (630A, B and C) (FIG. 1), or may be installed diagonally downward over the entire peripheral edge 604 of the top surface 606 (FIG. 5). ), In the case of FIG. 5, mist formation by a two-fluid nozzle or steam spray is suitable. More specifically, a plurality of mist spray nozzles 650 are spaced apart in the longitudinal direction of a supply pipe 640 connected to a fluid or steam supply source (not shown) over the entire peripheral edge 604 of the top surface 606. It is installed diagonally downward to supply mist over the entire close snowfall space 600.

Next, the partition extending in the horizontal direction will be described. As shown in FIGS. 2 and 3, the plurality of rollers 306 are arranged above the closed snowfall space 600 so as to partition the closed snowfall space 600, respectively. The roller 306 constitutes a rotary brush 314 in which hair is transplanted on the outer peripheral surface 312, and a large number of through holes 316 are provided on the outer peripheral surface 312 so that air is ejected from the inside of each roller 306 through the through holes 316. I have to.
As a modification, a plurality of dimple-shaped depressions of a golf ball are provided over the entire outer peripheral surface of one of the adjacent rotating brushes 314, whereby, as will be described later, a roller 306 in which snowflaked crystalline snow is adjacent. When passing through the narrowest part between them, it is possible to maintain the crystalline state of fragile crystalline snow. The width and depth of the plurality of depressions may be determined from this point of view.
The rotary brush 314 may be made of, for example, a resin-made flexible material, the tip of which may have a length of contact with the outer peripheral surface 312 of the opposing roller 306, and the diameter of the rotary brush 314 and the rotary brush 314. The density on the outer peripheral surface 312 of the roller 306 of 314 may be appropriately determined from the viewpoint of the area where snow particles can adhere on the outer peripheral surface 312 of the roller 306 excluding the rotating brush 314.
The air may be ejected in a pulsed manner, and by setting the temperature of the air to -1 ° C or lower, even if the temperature in the closed snowfall space 600 is zero or higher, this atmosphere is created by the rotating brush 314. And it is possible to prevent direct contact with the roller 306 and thereby prevent the generated snowflakes from melting. The density of the air through holes 316 may be determined from this point of view. The air volume may be determined from the viewpoint of not breaking the crystals of crystalline snow.

In the case of the roller 306 with the rotating brush 314, since the attached snow particles are not compacted, it is suitable for peeling the crystalline snow from the roller 306 with the rotating brush 314 to simulate snowfall, but in particular, the rotating brush 314 has a high density. By setting the length to reach the outer peripheral surface 312 of the opposing rollers 306, it is possible to partition the closed snowfall space 600 by arranging the rollers 306 in the horizontal direction, and within the closed snowfall space 600. , The snow-making space and the snow-falling space are set as temperature regions independent of each other. When simulating snowfall using snowflakes that have been created and generated, it is possible to set the snowfall space to zero or higher and to make the snow wet during snowfall.

Below the rotary brush 314 group that generates snowflakes, a retractable wire mesh 500 arranged so as to hit the brush tip of the rotary brush 314 group is provided.
Even with the rotating brush 314 group, large lumpy snowflakes may fall as they are, and the retractable wire mesh 500 is provided to prevent such heavy snowflakes from falling as it is, and the material and mesh diameter of the wire mesh are different. Although optional, the mesh size is smaller than the size of the large lumpy snowflakes, for example, 5 mm to 8 mm, from the viewpoint that the large lumpy snowflakes do not fall as they are.
The retractable wire net 500 is provided so as to have a width longer than the axial length of the rotary brush 314 group and extend from the rotary brush 314 at one end of the rotary brush 314 group to the rotary brush 314 at the other end, and each of the rotary brush 314 groups. Since the length of the brush provided on the rotating brush 314 from the center of the rotating brush 314 is uniform, the retractable wire net 500 is installed in a substantially horizontal direction.

The take-up wire mesh 500 has a take-up portion 502 for each of the rotary brushes 314 at both ends, and a known rotary motor 506 is provided in one of the rotary brushes 314, and can be reciprocated in the horizontal direction by the rotation of the rotary motor 506. ..
The retractable wire net 500 needs to be reciprocated horizontally while generating snowflakes during the rotation of the rotary brush 314 group, and the horizontal movement speed of the retractable wire net 500 is the rotation speed of the rotary brush 314. It may be set according to the speed, but it is set lower than the peripheral speed of the tip of the rotating brush 314. As a result, the snowflakes pass through the mesh of the retractable wire mesh 500 that is moving in the horizontal direction, and the time until the snow falls is secured.

A fixed brush 504 is provided below the retractable wire mesh 500 so that the tip of the brush faces upward and hits the lower surface 510 of the retractable wire mesh 500. A plurality of fixed brushes 504 are provided, and it is preferable that each fixed brush 504 is provided below a position where the brushes of the adjacent rotating brushes 314 of the rotating brush 314 group mesh with each other, that is, a position where snowflakes are generated. As a result, the snowflakes adhering to the lower surface 510 of the retractable wire mesh 500 are scraped off by the fixing brush 504 to ensure that the snow falls.

According to the above configuration, the snowflakes are received and wound by the upper surface 508 of the retractable wire mesh 500 that is moving in the horizontal direction by being guided downward by the rotating brush 314 during the rotation of the rotating brush 314 group. When the retractable wire mesh 500 hits the tip of the brush of the rotary brush 314 group, the crystal snow that has become heavy snowflakes is repelled in the vertical direction, whereby the snowflakes on the upper surface 508 of the retractable wire mesh 500 are fragmented and wound up. After passing through the mesh of the type wire mesh 500, it becomes possible to snow. At that time, the snowflakes adhering to the lower surface 510 of the retractable wire mesh 500 are scraped off by the fixing brush 504 to ensure that the snow falls.
When the take-up wire net 500 is wound by any of the rotary brushes 314 at both ends during the horizontal movement, the take-up wire net 500 is horizontal by reversing the rotation direction of the rotary motor 502. It may be moved in the opposite direction, and the retractable wire net 500 may be reciprocated in the horizontal direction in this way.
As described above, in the case where the retractable wire mesh 500 is not provided by providing the retractable wire mesh 50 arranged so as to hit the brush tip of the rotary brush 314 group below the rotating brush 314 group that generates snowflakes. In comparison with the above, it is possible to perform a more partitioning function in cooperation with the rotating brush 314 group and the retractable wire mesh 500 according to the mesh of the retractable wire mesh 500.

The operation of the wet snow device 100 having the above configuration will be described below together with the wet snow method.
First, a snowfall space is prepared by a wet snow conversion device and a temperature / humidity adjustment device. More specifically, the ambient temperature and humidity in the snowfall space are set to a predetermined value, a plurality of rollers 306 are continuously rotated, and a mist composed of water droplets having a predetermined particle size is set to a predetermined temperature and / or humidity. Generated in the air within a closed snow space 600 controlled to be maintained within range.
It is preferable to adjust the particle size of the mist and / or the density of water droplets in the mist according to the time during which the snowfall can be moistened to achieve the desired moisture content, and the predetermined particle size is 5 microns or more. It is 30 microns and the density of water droplets in the mist is 1-10 g / m3.
The space in which the mist is generated should have a stage of maintaining above the saturated humidity.
The mist may be generated by blowing out air and water from the two-fluid nozzle, and may be continuously blown out during wet snow, or the mist may be generated by using a humidifying pan.

Next, in the upper part of the space partitioned vertically by a partition extending in the horizontal direction, below freezing point, moist air containing water vapor above ice saturation generates frost-like crystalline snow on the outer surface of the mesh-like film body. Drop off the crystal snow that has been made.
Crystalline snow is received in the space above the narrowest part between the adjacent rollers 306, becomes heavy snowflakes, and the adjacent roller 306 rotates in the direction toward the narrowest part between the adjacent rollers 306. The heavy snow fragmented crystal snow passes through the narrowest part and is guided downward. At that time, the heavy snow fragmented crystal snow is repelled by the tip of the rotating brush 314, and the crystal itself is not broken and becomes heavy snow fragmentation. Crystallized snow is turned into small snowflakes.
At the same time, in the narrowest part between the adjacent rollers 306, the brushes overlap each other to form a partition, so that the lower space is used to moisten the crystalline snow during snowfall at the lower part of the space. By raising the temperature, it is possible to prevent the updraft from reaching the upper part of the space, so that the updraft does not interfere with the snowfall and does not hinder the growth of crystals in the snow-making part. Therefore, by passing the snowfall through the mist, it is possible to make the crystalline snow wet during the snowfall while preventing heavy snow fragmentation.

At that time, every other roller 306 is sent downward, and the small snowflakes are sent downward by the rotation of the roller 306 and fall down as they are, simulating snowfall, for example. Snow is accumulated on the upper part of the vehicle V, which is the test body.

In the narrowest portion 304, since the upper space and the lower space of the closed snowfall space 600 are substantially separated by a plurality of rollers 306, in the short term, the crystal snowfall portion is to be crystallized. By suppressing the updraft to the snow part, it is possible to prevent the snowfall in the crystal snowfall part from being hindered, and in the long term, the temperature inside the crystal snowfall part and the temperature inside the crystal snowfall part become uniform. As a result, it is possible to prevent the temperature inside the crystal snowfall portion from dropping and hindering the wet snow formation in the crystal snowfall portion.

According to the method for moistening snowfall of the present invention having the above configuration, only the temperature in the closed snowfall space is controlled within a predetermined range according to the allowable variation of the required moisture content of the snow in the closed snowfall space. The choice is to control the temperature and humidity in the closed snowfall space within a predetermined range, or to form mist in the closed snowfall space while controlling the temperature and humidity in the closed snowfall space within a predetermined range. By doing so, if it becomes wet by melting the snow during snowfall, if the temperature in the closed snowfall space is too low, it is insufficient for wet snow, and if the temperature is not too low but the humidity is too low, While there is a possibility of refreezing, the melting time may be insufficient depending on the given snowfall time, and even if it can be thawed, the water content tends to vary depending on the location in the closed snowfall space. However, if it becomes wet by passing snow through the mist during snowfall, the water content varies depending on the location by forming the mist in the entire closed snowfall space without such restrictions on temperature and humidity. As described above, it is possible to achieve a desired water content in a limited closed snowfall space regardless of the type of snow.
As shown in FIG. 4, when the natural snow is wetted during snowfall outdoors, the wet snow making device 100 itself is carried out outdoors and the natural snow is received by the plurality of rollers 306. The wet snow may be formed in the closed snowfall space 600. In this case, the wet snow device 100 may be adjusted according to the wetness of the natural snow itself to adjust the water content.

Although the embodiments of the present invention have been described in detail above, those skilled in the art can make various modifications or changes within the scope of the present invention.
For example, in the present embodiment, as an aspect of achieving partitioning and light snow fragmentation, in the present embodiment, a retractable wire mesh arranged so as to hit the brush tip of the rotating brush 314 group has been described, but the present invention is limited thereto. Instead of being mobile like the retractable wire mesh, the snowflakes on the upper surface 508 of the retractable wire mesh 500 may be turned into small snowflakes by applying vibration with a fixed type.

The schematic perspective view which shows the embodiment of the wet snow conversion apparatus 100 of crystal snow which concerns on this invention. FIG. 3 is a schematic cross-sectional view showing details of a partition in the embodiment of the crystal snow wetting device 100 according to the present invention. FIG. 6 is a schematic view showing details of a rotating brush in the embodiment of the crystal snow wetting device 100 according to the present invention. In the embodiment of the crystal snow wetting device 100 according to the present invention, it is a diagram similar to FIG. 1 showing a situation in which natural snow is wetted outdoors. The same schematic perspective view as FIG. 1 which shows the modification of the crystal snow wetting apparatus 100 which concerns on this invention.

100 Wet snow device 306 Roller 308 Test room 310 Concavo-convex part 314 Rotating brush 316 Through hole 500 Rewinding wire net 502 Rewinding part 504 Fixed brush 506 Rotating motor 508 Top surface 510 Bottom surface 600 Sealed snowfall space 601 Caster 602 Peripheral side surface 604 Upper edge 606 Top surface 610 Air outlet 620 Air suction port 630 Mist supply port 640 Supply pipe 650 Mist spray nozzle

Claims (1)

In a snowfall space, a mist consisting of water droplets of a predetermined particle size is generated in the air controlled so that the temperature and / or humidity is maintained within a predetermined range.
After the mist is generated in the entire snowfall space, there is a stage in which the snowfall is passed through the mist, and the snowfall passes through the mist generated in the snowfall space according to the available time for wet snowfall. Adjust the particle size of the mist in the range of 5 to 30 microns and / or the density of water droplets in the mist in the range of 1 to 10 g / m3 to achieve the desired moisture content of wet snow. A characteristic method of making snowfall wet.

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