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Characteristics of wind velocity and temperature change near an escarpment-shaped road embankment.

Kim YM, You KP, You JY - ScientificWorldJournal (2014)

Bottom Line: Artificial structures such as embankments built during the construction of highways influence the surrounding airflow.The construction of the embankment influenced surrounding temperatures.The degree of temperature change was large in locations with large level differences from the embankment at daybreak and during evening hours when wind velocity changes were small.

View Article: PubMed Central - PubMed

Affiliation: The Department of Architectural Engineering, Chonbuk National University, Jeonju 561-756, Republic of Korea.

ABSTRACT
Artificial structures such as embankments built during the construction of highways influence the surrounding airflow. Various types of damage can occur due to changes in the wind velocity and temperature around highway embankments. However, no study has accurately measured micrometeorological changes (wind velocity and temperature) due to embankments. This study conducted a wind tunnel test and field measurement to identify changes in wind velocity and temperature before and after the construction of embankments around roads. Changes in wind velocity around an embankment after its construction were found to be influenced by the surrounding wind velocity, wind angle, and the level difference and distance from the embankment. When the level difference from the embankment was large and the distance was up to 3H, the degree of wind velocity declines was found to be large. In changes in reference wind velocities around the embankment, wind velocity increases were not proportional to the rate at which wind velocities declined. The construction of the embankment influenced surrounding temperatures. The degree of temperature change was large in locations with large level differences from the embankment at daybreak and during evening hours when wind velocity changes were small.

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Distribution between wind velocity and temperature by time zone.
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fig14: Distribution between wind velocity and temperature by time zone.

Mentions: The distribution chart of wind velocities and temperatures following the construction of the embankment was examined. Figure 14 shows the distribution chart of hourly wind velocities and temperatures by experiment site. Based on geographical characteristics, 18 days' worth of data from a high-level site (+1.2 m based on the embankment site) and a low-level site (−13.6 m based on the embankment site) were used. To understand the characteristics of wind velocities and temperature changes, an hourly analysis (18 pm–6 am and 6 am–18 pm) was performed. Wind velocity changes at dawn and during evening hours were very low at below 0.3–0.5 m/s. The low-level site (temperature 1) below the embankment showed temperature changes in the range of 0 to −4°C, while the high-level site showed temperature changes ranging from 0.4 to −0.4°C. The low-level site revealed a larger range of temperature changes than the high-level site. During the hours when the measured wind velocity was very low at 0.5 m/s, the low-level site recorded below-zero temperatures in all temperature ranges. The low-level site's minimal temperature of −4°C showed a temperature difference over ten times that of the high-level site within the same range of wind velocities. During the morning and afternoon hours when the wind velocity was measured at 2.4 m/s or lower, the difference between the maximum and minimum temperatures in the low-level site was 10°C. However, the difference in the high-level site was 5°C. Regarding the characteristics of hourly temperatures, it was confirmed that the embankment reduced the wind velocity and lowered the temperature to the below-zero range. It was also determined that stagnant regions without wind velocity changes due to the embankment influenced the temperature.


Characteristics of wind velocity and temperature change near an escarpment-shaped road embankment.

Kim YM, You KP, You JY - ScientificWorldJournal (2014)

Distribution between wind velocity and temperature by time zone.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4127258&req=5

fig14: Distribution between wind velocity and temperature by time zone.
Mentions: The distribution chart of wind velocities and temperatures following the construction of the embankment was examined. Figure 14 shows the distribution chart of hourly wind velocities and temperatures by experiment site. Based on geographical characteristics, 18 days' worth of data from a high-level site (+1.2 m based on the embankment site) and a low-level site (−13.6 m based on the embankment site) were used. To understand the characteristics of wind velocities and temperature changes, an hourly analysis (18 pm–6 am and 6 am–18 pm) was performed. Wind velocity changes at dawn and during evening hours were very low at below 0.3–0.5 m/s. The low-level site (temperature 1) below the embankment showed temperature changes in the range of 0 to −4°C, while the high-level site showed temperature changes ranging from 0.4 to −0.4°C. The low-level site revealed a larger range of temperature changes than the high-level site. During the hours when the measured wind velocity was very low at 0.5 m/s, the low-level site recorded below-zero temperatures in all temperature ranges. The low-level site's minimal temperature of −4°C showed a temperature difference over ten times that of the high-level site within the same range of wind velocities. During the morning and afternoon hours when the wind velocity was measured at 2.4 m/s or lower, the difference between the maximum and minimum temperatures in the low-level site was 10°C. However, the difference in the high-level site was 5°C. Regarding the characteristics of hourly temperatures, it was confirmed that the embankment reduced the wind velocity and lowered the temperature to the below-zero range. It was also determined that stagnant regions without wind velocity changes due to the embankment influenced the temperature.

Bottom Line: Artificial structures such as embankments built during the construction of highways influence the surrounding airflow.The construction of the embankment influenced surrounding temperatures.The degree of temperature change was large in locations with large level differences from the embankment at daybreak and during evening hours when wind velocity changes were small.

View Article: PubMed Central - PubMed

Affiliation: The Department of Architectural Engineering, Chonbuk National University, Jeonju 561-756, Republic of Korea.

ABSTRACT
Artificial structures such as embankments built during the construction of highways influence the surrounding airflow. Various types of damage can occur due to changes in the wind velocity and temperature around highway embankments. However, no study has accurately measured micrometeorological changes (wind velocity and temperature) due to embankments. This study conducted a wind tunnel test and field measurement to identify changes in wind velocity and temperature before and after the construction of embankments around roads. Changes in wind velocity around an embankment after its construction were found to be influenced by the surrounding wind velocity, wind angle, and the level difference and distance from the embankment. When the level difference from the embankment was large and the distance was up to 3H, the degree of wind velocity declines was found to be large. In changes in reference wind velocities around the embankment, wind velocity increases were not proportional to the rate at which wind velocities declined. The construction of the embankment influenced surrounding temperatures. The degree of temperature change was large in locations with large level differences from the embankment at daybreak and during evening hours when wind velocity changes were small.

Show MeSH
Related in: MedlinePlus