Development of New Type Snow Fence with Airfoil Snow Plates for Prevention of Blowing-Snow Disasters. 1st Report. Evaluation of Performance by Blowing-Snow Simulation in Wind Tunnel.

AbstractSnowdrifting processes and the wind-velocity profiles around a collector and a blower snow fence were investigated in a cold wind tunnel. The purpose was to ascertain the effect of wind direction on drift control by snow fences. Three different cases were studied for both types of snow fence, and the resultant snowdrifts were compared. In the first case, the snow fence was perpendicular to the wind direction. In the second and third cases, it was tilted by 30° and 45°. When the collector snow fence was tilted, the amounts of snowdrift were much less than when the fence was perpendicular to the wind direction, because the area with low wind velocity was reduced to half behind the tilted fence. On the other hand, the blowing effect of the blower snow fence increased when it was set up at an angle to the wind direction. It is necessary to investigate the position where the blown snow is deposited by the tilted blower snow fence.

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Investigating Safety Effectiveness of Wyoming Snow Fence Installations Along a Rural Mountainous Freeway

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/2613-02 ◽

2017 ◽

Vol 2613 (1) ◽

pp. 8-15 ◽

Cited By ~ 6

Author(s):

Thomas Peel ◽

Mohamed Ahmed ◽

Noriaki Ohara

Keyword(s):

Empirical Bayes ◽

Winter Season ◽

High Rate ◽

Control Surface ◽

Blowing Snow ◽

Snow Fence ◽

Adverse Weather ◽

Safety Effectiveness ◽

State And Local ◽

Snow Fences

Drifting and blowing snow is a problematic and dangerous aspect of Interstate travel in the state of Wyoming. The control of snow and the maintenance of roadways is an essential and significant task for many state and local agencies. Many significant factors—such as vehicle control, surface conditions, and visibility—can be affected by hazardous winter weather. In areas such as the inspected 19-mi section of Interstate 80, snow fences have become a common and practical method of mitigating the problems caused by large quantities of snow near or on the traveled way. Wyoming deals with a high rate of adverse weather–related crashes during the winter season. Naive before–after analyses of snow fence installations have historically indicated a slight decrease in such crashes. In this study, the safety effectiveness of snow fence installations was investigated; more rigorous quantitative-based approaches were used and included a before–after analysis with empirical Bayes—in which Wyoming-specific safety performance functions were used—and odds ratio analyses. Crash modification factors were estimated for various crash types and severity levels. The results from this study indicate that the installation of snow fences contributes to a significant increase in the safety effectiveness of Interstate use during the winter. Specifically, it was found that during adverse weather conditions, snow fences decreased total crashes and fatal and injury crashes by about 25% and 62%, respectively.

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Development and Practical Application of High-Performance Snow Fence for Prevention of Blowing-Snow Disasters

The Proceedings of Conference of Hokkaido Branch ◽

10.1299/jsmehokkaido.2003.43.74 ◽

2003 ◽

Vol 2003.43 (0) ◽

pp. 74-75

Author(s):

Tomohiro HATANO ◽

Hiroshi SAKAMOTO ◽

Kazunori TAKAI ◽

Yoshihiro OBATA

Keyword(s):

High Performance ◽

Blowing Snow ◽

Practical Application ◽

Snow Fence

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Study on Transient Dynamics and Aerodynamic Characteristics of a New Type of High-Damping Four-Winged Rotating Parachute Inflation Process

Mathematical Problems in Engineering ◽

10.1155/2020/2361534 ◽

2020 ◽

Vol 2020 ◽

pp. 1-20

Author(s):

Yang Li ◽

Chunlan Jiang ◽

Liang Mao ◽

Ming Li

Keyword(s):

Wind Tunnel ◽

Aerodynamic Characteristics ◽

Resistance Coefficient ◽

Fe Model ◽

Wind Tunnel Tests ◽

Development Cycle ◽

Military Background ◽

New Type ◽

Parachute Inflation ◽

The Cost

To decrease the opening shock as well as improve the resistance coefficient and stability of the parachute of aviation weapon under subsonic conditions, a new kind of high-damping four-winged rotating (HFWR) parachute is investigated in this paper. The transient dynamic behavior and aerodynamic characteristics of the parachute during the inflation process are studied. Considering the permeability, the 3D folded finite element (FE) model of the HFWR parachute is established based on the direct folding modeling technique, and the inflation process of the parachute under subsonic flow is simulated using the multimaterial arbitrary Lagrange–Euler (ALE) method. A series of wind tunnel tests are conducted to verify the numerical results. Besides, the opening performances of the HFWR parachute and the round parachute, which includes the inflation process, the dynamic response of the swing angle, and the opening shock load varying with time, are compared under the same conditions. The results show that the opening performance of the HFWR parachute is superior to the round parachute under specific military background. The fluid-structure interaction (FSI) simulation results show good consistency with the wind tunnel tests, which indicates that the numerical modeling can effectively simulate and predict the opening performance and aerodynamic characteristics of the rotating parachute. The modeling method in this paper can help shorten the development cycle, improve the cost effectiveness, and optimize the design of the parachute.

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Snow Control Studies of Elevated Buildings in the Antarctic

Annals of Glaciology ◽

10.1017/s0260305500005450 ◽

1983 ◽

Vol 4 ◽

pp. 188-191

Author(s):

Hiromi Mitsuhashi ◽

Toshio Hannuki ◽

Toshio Sato ◽

Kou Kusunoki

Keyword(s):

Wind Tunnel ◽

Blowing Snow ◽

Wind Tunnel Experiments ◽

Syowa Station ◽

Design Concepts ◽

Drifting Snow ◽

Scale Models ◽

The Difference ◽

Wind Profiles ◽

The Antarctic

To elaborate design concepts of elevated buildings in an area of drifting snow, snow deposition and wind profiles around two buildings at Syowa station, Antarctica, were observed in 1978. To interpret the observed results in detail, wind-tunnel experiments on scale models were carried out. A wind-scooped snow deposit was formed behind the building and a sharp ridge was formed on the lee side. The highest point of the deposit was at a distance of 1 or 1.5 times the floor height (about 1.5 m) and the skirt of the snowdrift extended about 5 times the height of the roof. Wind profiles measured near one of the buildings (ionosphere hut) were expressed in terms of the logarithmic law. Two methods based on wind-tunnel experiments were used to estimate the development of snowdrifts around the building: one is to estimate the deposition from the difference in transport of blowing snow calculated from wind profiles and snowdrift flux profiles, the other is by deduction from the distribution of wind profiles. These experiments together with previous ones indicated that the optimum floor height was about 44Î of the height of the building.

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Wind-Tunnel Experiments on Blowing Snow

Annals of Glaciology ◽

10.1017/s0260305500010004 ◽

1985 ◽

Vol 6 ◽

pp. 63-67 ◽

Cited By ~ 21

Author(s):

N. Maeno ◽

R. Naruse ◽

K. Nishimura ◽

I. Takei ◽

T. Ebinuma ◽

...

Keyword(s):

Wind Tunnel ◽

Pressure Gradient ◽

Blowing Snow ◽

Wind Tunnel Experiments ◽

Complex Dynamic ◽

Turbulent Diffusion Coefficient ◽

Wide Range ◽

The Mean ◽

Cold Wind ◽

Snow Drifting

Blowing snow was produced artificially in a cold wind-tunnel, and various measurements were conducted including particle diameters, concentrations, saltation lengths heat transport and electric charge. The mean diameter of blowing snow particles decreased only slightly with increasing height; in the saltation layer, standard deviation was large and velocities were scattered in a wide range, suggesting the complex dynamic process on taking-off. The mean saltation length ranged from a few cm to 40 cm increasing with wind velocity.When wind blew without snow drifting, the static air pressure on the snow surface was smaller at higher levels, the vertical pressure gradient being negative. The pressure gradient became positive when blowing snow was initiated eg +9.6 Pa/m at 11.2 m/s and -8.3 °C. The magnitude of à downward force acting on a saltating snow partice caused by the pressure gradient was not large enough to explain the downward acceleration found from photographic analyses of particle trajectories.Blowing snow particles were charged negatively the magnitude of charge increased with lowering temperature. Increase in vertical heat transfer was found in blowing snow by measuring the temperature of the air at various levels; the increase is reflected on that in the apparent turbulent diffusion coefficient.

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Wind-Tunnel Experiments on Blowing Snow

Annals of Glaciology ◽

10.3189/1985aog6-1-63-67 ◽

1985 ◽

Vol 6 ◽

pp. 63-67 ◽

Cited By ~ 4

Author(s):

N. Maeno ◽

R. Naruse ◽

K. Nishimura ◽

I. Takei ◽

T. Ebinuma ◽

...

Keyword(s):

Wind Tunnel ◽

Pressure Gradient ◽

Blowing Snow ◽

Wind Tunnel Experiments ◽

Complex Dynamic ◽

Turbulent Diffusion Coefficient ◽

Wide Range ◽

The Mean ◽

Cold Wind ◽

Snow Drifting

Blowing snow was produced artificially in a cold wind-tunnel, and various measurements were conducted including particle diameters, concentrations, saltation lengths heat transport and electric charge. The mean diameter of blowing snow particles decreased only slightly with increasing height; in the saltation layer, standard deviation was large and velocities were scattered in a wide range, suggesting the complex dynamic process on taking-off. The mean saltation length ranged from a few cm to 40 cm increasing with wind velocity.When wind blew without snow drifting, the static air pressure on the snow surface was smaller at higher levels, the vertical pressure gradient being negative. The pressure gradient became positive when blowing snow was initiated eg +9.6 Pa/m at 11.2 m/s and -8.3 °C. The magnitude of à downward force acting on a saltating snow partice caused by the pressure gradient was not large enough to explain the downward acceleration found from photographic analyses of particle trajectories.Blowing snow particles were charged negatively the magnitude of charge increased with lowering temperature. Increase in vertical heat transfer was found in blowing snow by measuring the temperature of the air at various levels; the increase is reflected on that in the apparent turbulent diffusion coefficient.

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Innovative Construction of 3-Component Aerodynamic Balance

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.542.171 ◽

2013 ◽

Vol 542 ◽

pp. 171-177 ◽

Cited By ~ 1

Author(s):

Jan Ryś ◽

Marcin Augustyn

Keyword(s):

Wind Tunnel ◽

Strain Gauge ◽

Aerodynamic Load ◽

Measuring Accuracy ◽

Load Factors ◽

New Type

This paper deals with a description of a new type an aerodynamic balance used in a wind tunnel for measuring forces acting on a model. A concept of the strain gauge balance in which the three component of aerodynamically force can be measured was presented. The tests proved good measuring accuracy of this construction. On the basis of such a solution three component of force and aerodynamic load factors can be easily evaluated.

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