JP2008063723A - Snow protection fence and method for enhancing snow blowing effect thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a snow blow off effect by adding an additional constitution through the use of an existing constitution of a snow protection fence. <P>SOLUTION: In this snow protection fence 10 which is obliquely provided in such a manner that the leeward side of a snow protection board 11 is directed downward with respect to the windward side thereof during snow protection, a wind shielding member 20 for shielding a wind flowing to the leeward side is provided above the snow protection board 11. The constitution like this makes a weak wind area formed on the leeward side, so as to improve the snow blow off effect. Otherwise, a low-pressure area enlarging member for enlarging a low-pressure area formed on the leeward side can also be provided above the snow protection board 11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a snow prevention technique, and is particularly effective when applied to a blow-off type snow fence.

  Regarding snow protection facilities, the “Road Structure Ordinance”, “Road Structure Ordinance Construction Rules”, etc. stipulate fine snow prevention facilities, etc., and ensure traffic safety in snowstorms. As such a puddle prevention facility, the “Explanation and Operation of Road Structure Ordinance” states that “depending on the road structure such as linear or cross-sectional shape, where there is a risk of puddles on the road due to topography, weather, etc. , Snowdwelling facilities such as snow shelters, snow fences, and snow forests shall be provided. "

  For snow fences, the snow fences are installed on the windward side of the road, and the wind speed is increased or decreased by the fence to prevent the generation of snowdrifts on the road. In addition to the survey of the topography and snowdrift, the location, height, gap, and bottom gap of the fence must be considered. "

  In this way, the snowdrift prevention facility, which is one of the snow prevention facilities, is regarded as a snowstorm countermeasure facility that prevents snowdrift caused by snowstorms and alleviates visibility problems, and one such snowstorm countermeasure facility is a snow fence. .

  Such snow fences include, for example, snowstorm fences, blow-off fences, blow-off fences, and blow-up fences. After appropriate examination of weather conditions, topographic conditions, etc., appropriate types are selected and used. Yes. Such fences are generally made of steel, but those using wood, concrete, plastic resin, etc. are also used.

  The type installed on the side of a road such as a national road is currently a blown snow fence. This is because it can be installed in a road site and a puddle is difficult to form on the leeward side. That is, in the blow-off method, the wind is blocked by a snow-preventing plate, and the strong wind that blows through the lower space of the fence blows off the snow on the road side and the road surface, thereby preventing visibility disturbance and puddles.

  With regard to such a blow-off type snow fence, it is possible to extend the blow-off distance by, for example, providing a baffle plate on the lower surface side of the snow prevention plate in Japanese Patent Application Laid-Open No. 2003-168256, allowing the ventilation to flow smoothly and obliquely downward and increasing the flow velocity. It is written.

  Further, in Patent Document 2, as viewed from the vertical direction as it goes from the uppermost snow barrier plate to the lowermost snow barrier plate, it is sequentially shifted to the road side along a curved curve that is concave outward, and A configuration in which the angle (tilt angle) that forms the vertical direction as the attachment angle goes from the top to the bottom is sequentially increased. With this configuration, the wind flow can be smoothly guided on the road surface by the lateral wind that blows through, and the distance of the complete blow-off of the road surface is about 7 m, which is about 1.5 times that of the conventional one. It is stated that the effect can be expected.

In Patent Document 3, a snow protection plate main body, which is formed by bending a plurality of portions in the plate width direction in order and having a downwardly convex shape, is attached to a support column with an interval in the vertical direction so that the blowing side becomes higher. Thus, it is disclosed that the shielding property for blocking the wind and the blowing property for blowing off snow on the road can be improved.
Japanese Patent Laid-Open No. 10-292319 JP 2005-42471 A JP 2002-138417 A

  As described above, various inventions have been proposed for the blow-off type snow fence. However, most of them have a configuration related to the snow plate, such as a snow plate itself and a method for attaching the snow plate.

  Snow fences are already widely used in snowy areas such as Hokkaido and Tohoku, and there are few requests for new snow fences. Under such circumstances, the present inventor considered that the use of the existing snow fences can improve the blowing effect at a low cost, which is a measure that is currently required.

  Certainly, although the proposed invention is excellent, if the structure of the snow protection board or the snow fence itself is changed, enormous expenses must be prepared for the modification of the existing snow fence. It seems that the current situation is that the renovation of the snow fence is not accepted by the drought as austerity measures are taken.

  Therefore, the present inventor considered that there is a method that can improve the blow-off effect by adding an additional configuration using the existing configuration of the snow fence.

  An object of the present invention is to improve the blow-off effect by adding an additional configuration using the configuration of an existing snow fence.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

The present invention is a snow fence that is provided with the leeward side of the snow proof plate facing downward from the windward side at the time of snow prevention,
The snow fence is provided with a low-pressure field growth member that enlarges the low-pressure field formed on the leeward side above the snow protection plate. In this configuration, the low-pressure field growth member is formed as a wind shielding member that blocks wind flowing toward the leeward side. Alternatively, the low-pressure field growth member is a windmill.

The present invention is a snow fence that is provided with the leeward side of the snow proof plate facing downward from the windward side at the time of snow prevention,
The snow fence is provided with a wind shield member for blocking wind flowing on the leeward side above the snow plate. In this configuration, the wind shielding member is a wind shielding plate that blocks the wind on the plate surface. Alternatively, the wind shield member is a windmill.

  In the snow fence having the above-described configuration, when the low pressure field growth member or the wind shielding member is formed on the windmill, the windmill generates electric power and the illumination lamp provided on the snowbreak plate is turned on. In this configuration, the illumination lamp is intermittently lit. The illumination lamp is an LED.

  In the snow fence having any one of the configurations described above, the design of the snow fence is performed by fluid numerical simulation. By adopting such a design method, it has become possible to develop a snow fence used in winter, for example, without performing a demonstration experiment waiting for winter. For example, a simple wind tunnel experiment can be performed in summer or the like, and the snow fence can be evaluated together with the experimental data.

  In the configuration of the snow fence, the low-pressure field growth member provided above the snow plate or the wind shield member provided above the snow plate includes a plurality of the snow plates provided in the uppermost stage. Is used.

  The present invention is a method for improving the blow-off effect in a blow-off type snow fence, wherein the low-pressure field growing member increases the low-pressure field formed on the leeward side different from the snow plate above the blow-off type snow fence. And the blow-off effect is improved by making the low-pressure field on the leeward side larger than when the low-pressure field growth member is not provided. Alternatively, using the snow protection plate at the uppermost stage of the blow-off type snow protection fence having a plurality of snow protection plates as a low pressure field growth member for increasing the low pressure field formed on the leeward side, the low pressure field on the leeward side, It is characterized in that the blowing effect is improved by making the uppermost snow protection plate larger than the case where it is not used as a low pressure field growth member.

  The present invention is a method for improving the blow-off effect in the blow-off type snow fence, and is provided above the blow-type snow fence with a wind-shielding member that blocks wind flowing on the leeward side different from the snow-prevention plate, It is characterized by improving the blowing effect by making the weak wind area on the side larger than the case where the wind shielding member is not provided. Alternatively, the uppermost snow protection plate of the blow-off type snow protection fence having a plurality of snow protection plates is used as a wind shielding member that blocks the wind flowing to the leeward side, and the weak wind area on the leeward side is used as the uppermost snow protection plate. It is characterized in that the blowing effect is improved by making the plate larger than the case where the plate is not used as the wind shielding member.

  In the configuration in which the uppermost snow guard plate is used as a low pressure field growth member or a wind shield member, the application of the method for improving the blowing effect of the snow guard is applied to an existing snow guard already installed. And

  Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

  In the present invention, since the low-pressure field growth member that enlarges the low-pressure field formed on the leeward side or the wind-shielding member that blocks the wind flowing on the leeward side is provided, compared to the case where such a configuration is not provided, the snowproof plate The blowing effect by the wind passing through is improved.

  In addition, if a windmill is used for such a low-pressure field growth member or windshield member, it is possible to easily perform night illumination provided on the snow fence by windmill power generation even in areas where it is difficult to secure power supply. It is possible to prevent such collision accidents.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof may be omitted.

  The present invention has a configuration in which some obstacles are provided above the snow fence so that the low-pressure field is increased on the leeward side. Such an obstacle is provided, for example, at a position above the snow protection plate and functions as a low-pressure field growth member, and may basically have any configuration. For example, the low-pressure field growth member may be configured as a wind-shielding member that blocks the wind flowing toward the leeward side and grows the low-pressure field on the leeward side.

  The snow fence having such a configuration can be confirmed with a blow-off type snow fence. Of course, although the effect on the blow-off effect itself cannot be expected, it is possible to add a configuration similar to that of the present invention to other types of snow fences.

(Embodiment 1)
As shown in FIGS. 1A and 1B, in the snow fence 10 of the present embodiment, which is a blow-off type (in the figure, sometimes referred to as a blow-off type), the snow-preventing plate 11 is a frame body 12. Is provided. The frame body 12 is configured so that the snow plate 11 can be attached with, for example, a steel pipe or the like.

  In the case shown in the figure, a plurality of snow protection plates 11 such as four are provided. As shown in FIG. 1B, each of the four snow protection plates 11 is formed in a substantially flat plate shape having a rectangular shape, and its longitudinal direction is constructed in the front lateral direction of the frame body 12. Each of the four installed snow protection plates 11 is configured such that the plate surface is directed obliquely with respect to the frame body 12. With this configuration, during snow protection, the snow protection plate 11 is provided at an angle in a range of 15 degrees or more and 60 degrees or less with respect to the horizontal direction by lowering the leeward side from the windward side, thereby exhibiting a blow-off function. It can be done.

  In the snow fence 10 having such a configuration, as shown in FIG. 1A, a wind shielding member 20 according to the present invention is provided above the snow protection plate 11 at the uppermost stage. For example, as shown in FIG. 1B, the wind shield member 20 is configured as a rectangular plate-like wind shield plate 20 a. The wind shielding plate 20a is formed, for example, in a single sheet configuration, and the longitudinal direction thereof is provided along the front lateral direction of the frame body 12 as shown in FIG. For example, the plate surface is set up vertically so that the wind can be blocked by the plate surface of the wind shield plate 20a.

  Since the wind shielding plate 20a receives wind such as snowstorm from the front side of the windward side, for example, the leeward side may be supported by the frame 12 so as not to collapse by the wind. In addition, in some cases, the snow fence 10 itself may be reinforced. Further, the snow fence 10 is provided such that a predetermined gap is provided between the snow protection plate 11 on the lowermost stage side and the installation surface GL of the snow fence 10.

  As shown in FIG. 2, in the snow fence 10 configured in this way, as shown in FIG. 2, since the wind is blocked to some extent by the wind shielding member 20 formed on the wind shielding plate 20a on the leeward side, a weak wind region is formed. The Rukoto. Such a weak wind region is a low pressure field lower than the surrounding pressure. A low-pressure field is formed as a static pressure field lower than the dynamic pressure field formed around.

  By forming such a weak wind region as a low-pressure field, the wind passing between the snow protection plates 11 is pressed further downward than when the wind shield member 20 is not provided. That is, the snow fence 10 is strongly pressed against the installation surface GL side. By providing the wind shield member 20 in this manner, the wind is pressed by the lower side, so that the wind speed is increased as compared with the case where the wind shield member 20 is not provided.

  Therefore, when the snow fence 10 having such a wind shield member 20 is installed on the side of a road or the like, the formation distance of the snowdrift to the road surface or the like on the leeward side of the snow fence 10 does not provide the wind shield member 20. It extends compared to the case. Even if a puddle is formed, it is possible to avoid formation of a puddle on a road surface or the like used for traffic of an automobile or the like by forming the puddle further away.

  Moreover, since the wind speed of the wind pressed downward is increased by providing the wind shield member 20 and the snow is blown strongly in the lateral direction, the snow soars more than when the wind shield member 20 is not provided. Therefore, visibility and visibility can be secured when driving a car or the like. Thus, by providing the wind-shielding member 20, it is possible to improve and improve the blowing effect.

  However, for example, as shown in FIGS. 3A and 3B, in the configuration in which the wind shielding member 20 is not provided, the flow of wind is as shown in FIG. In the case shown in FIG. 4, it can be seen that the low pressure field as the weak wind region formed on the leeward side is smaller than that in the case shown in FIG.

  When the weak wind region formed in this way, that is, the low pressure field is small, the wind passing through between the snow protection plates 11 flows as indicated by the arrows shown in FIG. 4 and tends to rise on the leeward side. Such a tendency is a phenomenon that occurs because the low-pressure field as a weak wind area formed on the leeward side is small, so that the wind is not strongly pressed against the road surface or the like, and the wind speed is weakened.

  In this way, with the simple configuration in which the wind shield member 20 is provided, it is possible to improve the blow-off effect due to the wind being reliably pressed against the road surface side or the like as compared with the case where the wind shield member 20 is not provided. That is, by adding the wind shield member 20 to the conventional blow-off type snow fence, the blow-off effect of the conventional blow type snow fence can be easily improved.

  Therefore, by adopting the present invention, it is possible to improve the functions of a large number of existing blow-off type snow fences without carrying out extensive repairs.

  As described above, the improvement of the blowing effect of the snow fence 10 according to the present invention is mostly achieved by the wind shield member 20, and the configuration of the snow shield plate 11 and the like provided below the wind shield member 20 is as follows. It can be said that there is not much relation.

  That is, in the present invention, it is important to provide the wind shield member 20, and the structure of the blow-off type snow fence having the snow-preventing plate 11 provided on the lower side of the wind shield member 20 is a basic blow-off. Any configuration can be used as long as the effect can be exhibited, and various configurations conventionally proposed may be adopted.

  Of course, the wind-off effect when the wind-shielding member 20 is provided is synergistic with the effect of improvement provided by the wind-shielding member 20 in addition to the wind-off effect of the blow-off type snow fence without the wind-shielding member 20 originally. Since it is grasped as being added, the overall effect including the added blow-off effect is basically the blow-off type of the blow-off type snow fence without the original wind-shielding member 20. The higher the effect, the better.

  The formation conditions of the weak wind region and the low-pressure field by the wind shielding member 20 can be confirmed by a fluid numerical simulation.

  For example, the snow fence 10 shown in FIG. 1 is used as a model for confirming the function of the wind shield member 20, and the model of the structure shown in FIG. A numerical simulation was applied to compare the blow-off effect.

  When applying the fluid numerical simulation, it is necessary to determine the dimensions of the snow fences 10 and 10a. The dimensions are determined as follows with reference to the existing snow fences of the conventional configuration.

  That is, as shown to Fig.5 (a), the snowproof board 11 was set to 5 mm in the range of thickness 5-20 mm, for example. Moreover, it assumed that it was formed in the flat form of 850 mm long x 20000 mm wide. It is assumed that the snow protection plate 11 is installed obliquely at an angle of 45 degrees, for example, in the range of θ = 15 to 60 degrees with respect to the horizontal direction on the leeward side.

  Furthermore, as shown in FIG. 5A, the wind shield 20a has a thickness of 5 to 20 mm, for example, 5 mm, a length of 300 to 1200 mm, for example, 500 mm (50 cm), and a width of 20000 mm. It shall be formed in flat form. The windshield plate 20a is attached at a position where the snow shield plate 11 is obliquely provided at the above angle with the plate surface being vertically at a position within a range of 0 to 300 mm, for example, 100 mm away. It was assumed that it was provided. The case of 0 mm indicates that there is no gap between the snow protection plate 11.

  Moreover, the thing of the structure which does not have the windshield 20a applied to a fluid numerical simulation as a contrast is a structure shown in FIG.5 (b), and excludes the structure regarding the windshield 20a in FIG.5 (a). Other configurations, dimensions, and the like were assumed to be set exactly the same as those using the wind shielding plate 20a.

  For the snow fences 10 and 10a having such a configuration, each model was virtually constructed on 556140 with 124 × 69 × 65 spatial meshes. For example, FIG. 6 shows a state in which a model of the snow fence 10a is constructed in the space mesh on the computer screen.

  For the fluid numerical simulation, a three-dimensional thermal fluid analysis program (Wind Perfect, manufactured by Environmental Simulation Co., Ltd.) was used. The upwind difference scheme (first order accuracy) was applied in the spatial direction and the semi-implicit method was used in the temporal direction. This was done by finding solutions for the steady state of the flow field and pressure field by the Time Marching Method. For example, the specification of Wind Perfect was as shown in FIG.

  FIG. 8 shows a wind speed vector distribution result of a fluid numerical simulation in the snow fence 10 provided with a 50 cm vertical wind shield 20a. FIG. 8 is originally displayed in color-coded display on the computer screen, but the color-coded display is reproduced with a pattern for easy understanding. In addition, in FIG. 9, the mode of FIG. 8 was shown with the diagram. Similarly, FIG. 10 shows the pressure distribution and the wind speed vector, and FIG. 11 shows the state of FIG.

  FIG. 12 shows the distribution result of the wind speed vector of the fluid numerical simulation configured in the snow fence 10a without the wind shield 20a. Although FIG. 12 is originally displayed by color coding, it is divided by a pattern for easy understanding. FIG. 13 is a diagram showing the state of FIG. Similarly, FIG. 14 shows a pressure distribution and a wind speed vector, and FIG. 15 shows a state of FIG.

  As a result of the fluid numerical simulation, when FIGS. 8 and 9 are compared with FIGS. 12 and 13, the maximum wind speed of the wind flowing on the road surface is, for example, 7 m / s as shown in FIGS. In the case of 12 and 13, it is 6 m / s, for example. Obviously, it is confirmed that the wind speed of the wind pressed against the road surface is improved by providing the wind shielding member 20.

  Further, comparing FIGS. 10 and 11 with FIGS. 14 and 15, the −20 Pa pressure field on the lee side of the snow fence 10 spreads toward the lee side of the snow fence 10 as shown in FIGS. 10 and 11. 14 and 15, the pressure field of -20 Pa is generated in two parts. Therefore, in the case of FIGS. 14 and 15, the wind easily flows between the two −20 Pa pressure fields, and a part of the wind that flows along the road surface faces upward.

  From these results, it can be confirmed that the snow blow fence 10 is superior to the snow fence 10a in terms of the blowing effect.

  Incidentally, the fluid numerical simulation was applied to the case where the wind shielding plate 20a configured to be 30 cm long was used as the wind shielding member 20, and the result was confirmed. The other configuration is the same as that shown in FIG. 5A except that the wind shielding plate 20a is formed in a length of 30 cm.

  In FIG. 16, the distribution result of the wind speed vector of the fluid numerical simulation in the snow fence 10 which provided the 30-cm long wind-shielding board 20a was shown. Although FIG. 16 is originally shown in a color-coded display, it is reproduced in a pattern for easy understanding. FIG. 17 is a diagram showing the state of FIG. Similarly, FIG. 18 shows a pressure distribution and a wind speed vector, and FIG. 19 shows a state of FIG.

  Thus, in the blow-off type snow fence, even in the fluid numerical simulation, the blow-type snow fence portion in which the wind shield member 20 is provided can be very easily provided by reliably providing the wind shield member 20 configured on the wind shield plate 20a. It can be confirmed that the blow-off effect can be improved.

  In the above configuration, as shown in FIG. 1, the number of the snow protection plates 11 is four. However, the number of the snow protection plates 11 is not necessarily limited to four, and can be changed as necessary. What is necessary is just to set to a suitable number of sheets, for example, even one sheet is possible in principle.

  Further, the wind shield member 20 may have any configuration as long as it can block the wind. That is, any obstacle may be used as long as it obstructs the wind by blocking the passage of the wind. In the case shown in FIG. 1, a wind shielding plate 20 a having a rectangular plate configuration is illustrated as a shape that can be easily put into practical use. Further, in order to easily perform experiments and the like, the wind shielding plate 20a is formed as a single sheet. However, when actually applied, the structure can be appropriately changed according to the actual situation at the time of installation. It goes without saying that it is a thing.

  For example, in actuality, it is expected that a considerable amount of wind will hit the installation of the snow fence 10, and the wind shield 20a having such a single structure increases the possibility of collapse due to the wind. A plurality of configurations may be used. A plurality of wind shielding plates 20a having a short length in the erection direction (width direction) to the frame body 12 are provided laterally instead of a single sheet configuration so that the wind can escape from between the adjacent wind shielding plates 20a. It does not matter if it is configured. That is, the one-sheet configuration is divided.

  In such a configuration, although the wind shielding effect is not 100%, the wind shielding effect can be sufficiently exhibited, and the low pressure field in the weak wind region on the leeward side is compared with the case where there is no such wind shielding plate 20a. It is possible to grow sufficiently and to improve the blowing effect.

  In FIG. 20, the modification of the windshield 20a was shown. (A) is the case of the wind-shielding board 20a of the structure which arranged the some board | plate horizontally and provided the slit which lets a wind pass between adjacent boards in the vertical direction. (B) shows a windshield plate 20a that can relieve the wind pressure to some extent by providing a large number of thin rods at a slight distance from each other, thereby making the plate surface of each plate extremely small. It is a configuration. (C) showed the structure of the wind-shielding board 20a which provided the long and narrow board | plate horizontally, and provided the slit from which a wind | blow passes between the board | substrates in the horizontal direction.

  In the above-described configuration in which the wind shielding plate 20a is divided into a plurality of fine unit plates, and slits that can reduce the wind pressure to some extent are connected to each other and connected, the direction of the slit is not limited to vertical and horizontal, but obliquely, etc. It may be provided, and its directionality can be freely configured.

  As shown in FIG. 20 (d), the wind shield plate 20a may be configured as a net. However, when configured as a net or the like, it is necessary to set the aperture ratio to 0.6 or less.

  Moreover, although the case where the wind shielding plate 20a is provided in the vertical direction is exemplified in the case of a single plate configuration or a configuration of a plurality of plates, such an installation method is shown in FIGS. 20 (e) and (f). In this way, the plate surface installation method itself can be changed so that the upper end is tilted to the leeward side or the upper end is tilted to the leeward side.

  Further, not shown in the figure, the windshield plate 20a is received by a vertically standing plate surface until a certain wind speed is reached, and when the wind speed exceeds a certain limit, the plate surface is inclined obliquely by the wind, Even if it is configured to escape, it does not matter. In such a configuration, when the wind weakens, it may be configured to be automatically restored by a spring or the like.

  In the above description, the configuration of the wind shielding plate 20a has been variously described. However, the wind shielding member 20 may not be formed in a plate shape as described above. For example, you may comprise in a lump shape like a block. Furthermore, it may be configured as a structure in which a number of holes or gaps through which a certain amount of wind passes are formed in a three-dimensional manner. For example, a configuration in which barbed wires are three-dimensionally entangled may be used.

(Embodiment 2)
In the said embodiment, the case where the wind-shielding member 20 was comprised in the wind-shielding board 20a etc. was illustrated and demonstrated. However, the action of the wind shield member 20 confirms that the wind shield member 20 promotes the growth of a low-pressure field on the leeward side in a sense as described above, if the viewpoint is changed.

  Therefore, the same effect as described in the above embodiment can be expected by providing a low-pressure field growth member 30 that greatly grows a low-pressure field on the leeward side instead of providing the wind-shielding member 20. That is, although the wind flows from the leeward side to the leeward side, the blow-off effect can be improved even if the low-pressure field growth member 30 that makes the low-pressure field grow larger on the leeward side.

  That is, as the low-pressure field growth member 30, for example, by weakening the wind passing from the leeward side to the leeward side, the static pressure field in the weak wind region formed on the leeward side can be made a lower pressure field. If so, the effect of blocking the wind may be substantially absent. It is confirmed that any member may be used as long as the energy of the passing wind is consumed in some form.

  The present inventor has conceived that, for example, a windmill 30a is used as the low-pressure field growth member 30 having such a configuration. As the windmill 30a to be used, a commercially available micro windmill with a short blade length was applied except for a blade whose blade length is about the side of the snow protection plate 11 of the snow fence 10.

  That is, as shown in FIGS. 21A and 21B, the wind turbine 30a has a blade length of 500 mm, which is a passing length of the blade 31, and is configured with four blades. Further, the generator 40 for generating power by the windmill 30a includes a stator and a core (not shown), and is built in an outer case of the body portion of the windmill 30a as shown in FIG. I used something.

  21A and 21B exemplarily show the dimensions of each part in order to show how the components of the windmill 30a are miniaturized.

  As shown in FIG. 22A, the small windmill 30 a is provided with a horizontal beam 12 a on the frame 12 of the snow fence 10 and is attached to the horizontal beam 12 a via a windmill mounting member 32. In the snow fence 10, 28 pieces were provided on the front side of the frame body 12 at a distance of 50 cm from the wing tip of the adjacent windmill 30 a. The snow fence 10 is further provided with an illuminating lamp 50 constituted by an LED 50a and the like on the support 12b.

  In the wind turbine 30a having such a configuration, the generator 40 is connected to a power generation amount measurement circuit as shown in FIG. 23 so that the power generation amount can be measured. Incidentally, the power source shown in FIG. 23 is provided for measuring the power generation amount of the windmill and the solar cell, and the solar cell is provided for the auxiliary power source.

  As shown in FIG. 24, the generator 40 having such a configuration is connected to a charge / discharge circuit, and can be charged or discharged as appropriate. The storage battery having such a configuration is connected to supply power to the LED 50a shown in FIG.

  Furthermore, as shown in FIG. 25, the LED 50a is connected to an electric circuit of a pulse controller, and is configured not to emit light continuously but to perform appropriate pulsed light emission. By performing such pulsed light emission, the LED 50a can emit light for a long period of time with the amount of power generated by the windmill 30a.

  The LED 50a may be mounted on the snow plate 11 as shown in FIG. 22B, for example, in addition to the mounting position on the support 12b as described above. In short, it may be provided at a position where a collision accident at night can be effectively prevented.

  As for the snow fence 10 when the windmill 30a having such a configuration is provided, the fluid numerical simulation is applied to verify the effect when the windmill 30a is provided, as in the above embodiment. In this verification, a circular plate satisfying the following specifications of the windmill 30a was used for convenience.

  In the model relating to the snow fence 10 provided with the windmill 30a, as shown in FIGS. 26 (a) and 26 (b), the distance between the centers of the adjacent windmills 30a is set to 700 mm, and 28 are provided between 20000 mm. Was assumed. Further, regarding the wind turbine 30a, the diameter was assumed to be 500 mm, the aperture ratio was set to 0.5528, and the resistance coefficient was set to 1.0. In addition, with respect to the snow protection plate 11 and the like, the same dimension setting and the like as in the above embodiment were performed.

  In the model having such a configuration, as shown in FIG. 26B, a fluid plate numerical simulation was performed by applying a circular plate having a thickness of 100 mm to the windmill 30a. Assuming the case where the snow fence 10 is provided in the range of 100 to 300 mm, for example, at a position of 100 mm, as shown in FIG. 26 (b), the windmill has a width in the range of 50 to 200 mm from the upper end position of the snow protection plate 11. It is assumed that 30a is provided.

  FIGS. 27A and 27B show a case where a model having a configuration in which such a windmill 30a is provided on 556140 spatial meshes similar to the above-described embodiment is shown.

  As a result of applying the fluid numerical simulation to the above model, a wind speed vector distribution result was obtained as shown in FIG. FIG. 28 is originally shown in a color-coded display, but is reproduced with a pattern for easy understanding. FIG. 29 is a diagram showing the state of FIG. Similarly, FIG. 30 shows the pressure distribution and the wind speed vector, and FIG. 31 shows the state of FIG. 30 as a diagram.

  As can be seen from FIGS. 28 and 29, the wind at the bottom of the snow fence 10 flows toward the leeward rear while maintaining a high wind speed. Under such circumstances, the low wind speed region on the leeward side of the snow fence is widened, and this is because the wind turbine 30 a is provided as the low pressure field growth member 30.

  Also, in the pressure distribution shown in FIGS. 30 and 31, it can be seen that the low pressure field generated on the leeward side is wide and strong. Since the low-pressure field spreads strongly in this way, it can be seen that the wind flowing over the snow fence 10 also flows parallel to the road surface where the snow fence 10 is set aside and does not reach the vicinity of the road surface.

  In addition, the wind flowing through the snow protection plate 11 at the uppermost stage of the snow protection fence 10 is peeled off and accelerated on the upper end side of the snow protection plate 11, but this accelerated wind is convenient for rotating the windmill 30a. That is, by providing the windmill 30a above the snow fence 10, the amount of power generation is also increased. Further, the windmill 30a is rotated by the accelerated wind, but the wind that has passed through the windmill 30a becomes a weak wind that has been decelerated on the leeward side to form a weak wind region that becomes a low-pressure field.

  The result of providing such a windmill 30a can be clearly understood by comparing with the results of FIGS. 12 to 15 described in the above embodiment.

(Embodiment 3)
In the above embodiment, the snow fence 10 provided with the structure of the wind shield member 20 or the low pressure field growth member 30 has been described. However, in this embodiment, the snow fence 10 having the structure described in the above embodiment is described. A design method using fluid numerical simulation will be described.

  When designing the snow fence 10 having a blow-off effect using the fluid numerical simulation, it is performed as follows.

  That is, in order to design using only the fluid numerical simulation, a target blow-off effect is first determined. For example, for the wind on the lower layer side (up to 2200 mm above the installation surface) that determines the blowing effect, the wind speed is 0.6 times the wind speed at the top of the snow fence, and the wind direction flows in parallel along the ground. Is determined to be at least three times the snowproof height.

  Next, a basic configuration of the snow fence 10 capable of exhibiting such an effect is formulated. In constructing such a basic configuration, for example, as shown in FIGS. 26 (a), (b), 27 (a), and (b), the shape of the snow fence 10 reproduced by a spatial mesh is a snow guard plate 11, The upper windmill 30a (or windshield 20a) may be used.

  Then, the effect of blowing off the snow fence 10 having the above basic configuration is confirmed by fluid numerical simulation. In confirming the blow-off effect, the expected blow-off effect can be obtained as much as possible by changing various dimensions of each part constituting the snow fence 10.

In confirming the blow-off effect, as described above, the shape of the snow fence 10 is reproduced with a spatial mesh. The actual scale of the finest spatial mesh is 50 mm. Snow fence 10
In order to reproduce the airflow on the leeward side, the space mesh on the leeward side of the snow fence is 200 mm or more on an actual scale.

Furthermore, the setting of the air flow analysis condition of the wind hitting the snow fence 10 having such a configuration is performed. In such airflow analysis, a turbulent flow model is adopted to reproduce the vortex generated behind the snow fence fence leeward side. The turbulent flow model includes a standard k-ε model and a LES model. In order to shorten the analysis time, the standard k-ε model is adopted in the present invention. The standard k-ε model sets four turbulent constants as follows: That is, σ _k = 1.0, σ _ε = 1.3, C ₁ = 1.44, C ₂ = 1.92 and C _μ = 0.09.

  When the height of the snow fence 10 to be analyzed is H, the dimension of the analysis space of the fluid numerical simulation is set to 4H or more in the vertical direction of the analysis space. The length of the windward side of the snow fence 10 is set to 10H or more, and the length of the leeward side is set to 20H or more.

  As shown in FIGS. 32, 33, and 34, the ground surface roughness classification and the power law are adopted as the condition of the wind hitting the snow fence 10. In the present invention, α = 0.27 is set and the wind speed at the height of the snow fence 10 is set to 10 m / s. It was assumed that the wind was directly in front of the snow fence 10.

  Regarding the above ground surface roughness classification, the actual wind speed distribution in the urban area is limited by measurement methods and so on, so there are still few examples actually investigated. For this reason, the correspondence between the basic characteristics such as the average wind speed and the vertical distribution of the intensity of turbulence and the representative wind (for example, the wind speed at the Yokohama Regional Meteorological Observatory) and the sky above the area including the target building is the building load. It may be set based on the guidelines and explanation (Architectural Institute of Japan).

  As shown in FIG. 32, the ground surface roughness classification is set in consideration of the state of the ground surface in each wind direction in the area including the target building. A vertical distribution of wind speed in FIG. 33 is assumed. From FIG. 34, the vertical distribution of the intensity of turbulence corresponding to the ground surface roughness classification is selected.

  In addition, when it is difficult to set the ground surface roughness classification for each of the 16 directions, when applying a common ground surface roughness classification for all wind directions, the ground surface will be on the dangerous side (the side where the predicted wind speed increases). It is necessary to set the roughness classification. For example, when the Yokohama Regional Meteorological Observatory is adopted as the representative wind, the surface roughness classification in all wind directions of the Yokohama Regional Meteorological Observatory is assumed to be IV, and the surface roughness classification in Yokohama City in all wind directions is assumed to be approximately III to IV. To do.

  A fluid numerical simulation is executed under such condition settings, and the result is that the dimensions of each part of the wind shielding plate 20a or the windmill 30a in the snow fence 10 that can obtain an effect as close as possible to the initial blow-off effect are found, and the shielding is performed according to the dimensions. By determining the shape of the wind plate 20a or the windmill 30a, the snow fence 10 can be designed appropriately.

  The air flow analysis of the snow fence 10 by the fluid numerical simulation has the following merits. The speed and direction of the wind blowing through the snow fence 10 can be grasped in detail. In the wind tunnel experiment, it was impossible to measure the pressure field, but the method using the fluid numerical simulation can predict the pressure field at the place reproduced by the spatial mesh.

  Further, by predicting such a pressure field, it is possible to estimate a wind load necessary for the structural design of the snow protection plate and the support column. A model of the snow fence 10 as in the wind tunnel experiment is not required. When snow is modeled by fluid numerical simulation, the amount of snow before and after the snow fence 10 can be predicted. For example, it is possible to predict how snow is carried by wind by arbitrarily setting the mass of snow and the adhesion of snow.

  As described above, with regard to wind, various theoretical pursuits have been made that can be applied mutatis mutandis as criteria for the application of fluid numerical simulations, but when such winds are entangled with snow, the theoretical development has not been fully developed. There is no current situation. In other words, it is difficult at present to predict the extent to which the blow-off effect will be improved by applying the calculation formula to what range the variables of the formula fall. The design method proposed in the present invention is proposed in view of the fact that the present situation can be overcome as much as possible.

(Embodiment 4)
In the present embodiment, the effect of blowing off is improved by changing the operation of the existing blow-off type snow fence. In the countermeasures described in the above embodiment, it has been described that the wind-shielding member 20 and the low-pressure field growth member 30 different from the snow protection plate 11 can be provided to improve the blowing effect. However, the present inventor has noticed that the blowing effect can be improved by changing the operation of the existing snow fence 10a.

  That is, although not shown in the drawing, the structure is a blow-off type snow fence 10a having a plurality of snow boards 11 and the topmost snow board 11 is regarded as the wind shield 20a or the low-pressure field growth member 30. By using the snow protection plate 11 so that the weak wind region (low pressure field) can grow substantially on the leeward side, the uppermost snow protection plate 11 can be used. Noticed that can be used as a different configuration and can improve the effect of the blow-off type.

  By adopting such a configuration, it is possible to easily improve the effect of the blow-off type by changing the method of using the uppermost snow protection plate 11 of the existing many snow fences 10a. In order to improve such an effect, the blow-off function is improved by providing the snow protection plate 11 in the range of 60 degrees or more and 90 degrees or less with respect to the horizontal direction with the leeward side lower than the windward side. .

  However, depending on how to stand the uppermost snow protection plate 11, for example, there is a possibility that the entire snow protection fence 10 may vibrate due to a snow-clad wind, so reinforcement may be necessary.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  The present invention can be effectively used in the field of snow fences, particularly in the field of blown snow fences.

(A) is sectional drawing which shows typically a mode that the structure of the blow-off-type snow fence of one embodiment of this invention was seen from the side, (b) is a state typically seen from the leeward side front FIG. It is explanatory drawing which shows the improvement effect of the blowing off effect of this invention. (A) is sectional drawing which shows typically a mode that the structure of the conventional blow-off-type snow fence was seen from the side surface, (b) is a front view which shows typically a mode seen from the leeward front. It is explanatory drawing which shows the conventional blow-off effect. (A), (b) is the front view and side view which show the model dimension in the case of performing the fluid numerical simulation of the blow-off type snow fence of this invention, (c), (d) is the snow fence of the conventional structure. It is the front view and side view which show the model dimension in the case of performing fluid numerical simulation. It is a figure which shows the mode in the space mesh in the fluid numerical simulation of the conventional blow-off type snow fence. It is explanatory drawing which shows the specification of Wind Perfect which is the fluid numerical simulation software. It is explanatory drawing which shows the mode of the wind speed vector in the fluid numerical simulation in the blow-off-type snow fence which provided the windshield. It is explanatory drawing which showed the mode shown in FIG. 8 with the diagram. It is explanatory drawing which shows the mode of the pressure distribution and wind speed vector in the fluid numerical simulation in the blow-off-type snow fence which provided the windshield. It is explanatory drawing which showed the mode shown in FIG. 10 with the diagram. It is explanatory drawing which shows the mode of the wind speed vector in the fluid numerical simulation of the conventional blow-off-type snow fence which does not provide a windshield. It is explanatory drawing which showed the mode shown in FIG. 12 with the diagram. It is explanatory drawing which shows the mode of the pressure distribution and the wind speed vector in the fluid numerical simulation of the conventional blow-off-type snow fence which does not provide a windshield. It is explanatory drawing which showed the mode shown in FIG. 14 with the diagram. It is explanatory drawing which shows the mode of the wind speed vector in the fluid numerical simulation in the modification of the blow-off-type snow fence which provided the windshield. It is explanatory drawing which showed the mode shown in FIG. 16 with the diagram. It is explanatory drawing which shows the mode of the pressure distribution and the wind speed vector in the fluid numerical simulation in the modification of the blow-off-type snow fence which provided the windshield. It is explanatory drawing which showed the mode shown in FIG. 18 with the diagram. (A)-(d) illustrates the modification of a windshield, (e), (f) is explanatory drawing which each showed the modification of the method of installation of a windshield. (A) is the front view which showed the structure of the windmill provided in a snow fence, (b) is a side view. (A)-(d) is a figure which shows typically the example which used LED for the illumination of the snow fence by windmill electric power generation. It is explanatory drawing which shows the electric power generation amount measuring circuit of a windmill. It is explanatory drawing which shows the charging / discharging circuit of a windmill. It is a circuit diagram which shows control of the pulse light emission of LED. (A), (b) is the front view and side view which show the model dimension in the case of performing the fluid numerical simulation when a windmill is provided in the snow fence. (A), (b) is a figure which shows the mode in the space mesh in the fluid numerical simulation of the snow fence of the structure which provided the windmill. It is explanatory drawing which shows the mode of the wind speed vector in the fluid numerical simulation in the blow-off-type snow fence which provided the windmill. It is explanatory drawing which showed the mode shown in FIG. 28 with the diagram. It is explanatory drawing which shows the mode of the pressure distribution and the wind speed vector in the fluid numerical simulation in the blow-off-type snow fence which provided the windmill. It is explanatory drawing which showed the mode shown in FIG. 30 with the diagram. It is explanatory drawing which shows the ground surface roughness division used with the design method concerning this invention. It is explanatory drawing which shows the wind speed condition on the ground surface corresponding to the ground surface roughness classification used with the design method concerning this invention. It is explanatory drawing which shows the strength of the disorder on the ground surface corresponding to the ground surface roughness classification concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Snow fence 10a Snow fence 11 Snow barrier 12 Frame 12a Horizontal rail 12b Post 20 Wind shield member 20a Wind shield plate 30 Low pressure field growth member 30a Wind turbine 31 Wing 32 Wind turbine attachment member 40 Generator 50 Illumination lamp 50a LED
GL installation surface

Claims (17)

A snow fence that is provided with the leeward side of the snow protection plate facing downward from the windward side during snow prevention,
The snow fence, wherein the snow fence is provided with a low-pressure field growth member that enlarges the low-pressure field formed on the leeward side above the snow board. In the snow fence according to claim 1,
The said low-pressure field growth member is formed in the wind-shielding member which shields the wind which flows to the leeward side, The snow fence which is characterized by the above-mentioned. In the snow fence according to claim 1,
The low-pressure field growing member is a windmill, and is a snow fence. A snow fence that is provided with the leeward side of the snow protection plate facing downward from the windward side during snow prevention,
The snow fence is characterized in that a wind shield member for blocking wind flowing on the leeward side is provided on the snow fence above the snow board. In the snow fence according to claim 4,
The snow shield fence is characterized in that the wind shield member is a wind shield plate that blocks wind on a plate surface. In the snow fence according to claim 4,
The snowbreak fence, wherein the windbreak member is a windmill. In the snow fence according to claim 3 or 6,
A snow fence, wherein power is generated by the windmill and an illumination lamp provided on the snow plate is turned on. In the snow fence according to claim 7,
The snow fence is characterized in that the illumination lamp is intermittently lit. In the snow fence according to claim 8,
The snow fence is characterized in that the illumination lamp is an LED. In the snow fence according to any one of claims 1 to 9,
The snow fence is designed by a fluid numerical simulation. In the snow fence according to claim 1 or 2,
The snow fence, wherein the uppermost one of the plurality of snow protection plates is used for the low pressure field growth member provided above the snow protection plate. In the snow fence according to claim 4 or 5,
The snow fence, wherein the top of the plurality of snow protection plates is used as the wind shielding member provided above the snow protection plate. It is a method for improving the effect of blowing off in the blow-off type snow fence,
When a low-pressure field growth member that enlarges the low-pressure field formed on the leeward side, which is different from the snow protection plate, is provided above the blow-off type snow fence, and the low-pressure field growth member is not provided on the leeward side. The improvement method of the blowing-off effect of the snow fence characterized by improving the blowing-off effect by making it larger than. It is a method for improving the effect of blowing off in the blow-off type snow fence,
Using the snow protection plate at the top of the blow-off type snow protection fence having a plurality of snow protection plates as a low pressure field growth member for increasing the low pressure field formed on the leeward side, A method for improving the blowing effect of a snow fence, wherein the snow blowing plate is made larger than when not used as a low pressure field growth member to improve the blowing effect. It is a method for improving the effect of blowing off in the blow-off type snow fence,
Provide a wind-shielding member that blocks wind that flows on the leeward side, which is different from the snow-prevention plate, above the blow-off type snow fence, and make the leeward side weaker wind area larger than when the wind-shielding member is not provided. And improving the blowing effect of the snow fence, characterized by improving the blowing effect. It is a method for improving the effect of blowing off in the blow-off type snow fence,
Using the snow protection plate at the top of the blow-off type snow protection fence having a plurality of snow protection plates as a wind shielding member that blocks the wind flowing to the leeward side, the weak wind area on the leeward side is used as the snow protection plate at the uppermost stage. The improvement method of the blowing off effect of the snow fence which improves a blowing off effect by making it larger than the case where it does not use as a wind-shielding member. In the improvement method of the blowing off effect of the snow fence according to claim 14 or 16,
The method for improving the blowing effect of the snow fence is applied to an existing snow fence already installed.

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