Contributions of Heat from Traffic Vehicles to Snow Melting on Roads
Contributions of Heat from Traffic Vehicles to Snow Melting on Roads
复制标题
交通车辆的热量对道路积雪融化的贡献
DOI：
10.3141/1672-05
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
Y. Kajiya
中科院分区：
文献类型：
--
作者：
N. Ishikawa;H. Narita;Y. Kajiya
对道路积雪的热平衡进行了分析，以研究冰膜的形成，并确定自然积雪的热平衡特征。融化自然积雪的主要热源是太阳辐射。然而，分析结果表明，由于雪的高反射率，吸收的太阳辐射减少，因此不能补偿长波辐射的热量损失。这种情况导致冬季净辐射为负。为了评价道路积雪的热平衡，通过测量车辆温度来估算车辆的红外辐射。这些测量结果表明，施加到雪的热输入随着车辆速度的降低和交通量的增加。提出了一个新的指标--阴影时间，它被定义为一段道路被车辆遮挡的时间。据确定，在20分钟的遮光时间内，入射长波辐射增加了50%，净辐射变为正值，这表明即使在冬季，在交通流量大的道路上也会发生积雪融化。
The heat balance of road snow was analyzed to examine ice-film formation and to determine the characteristics of heat balance on a natural snow cover. The main heat source used to melt natural snow cover is solar radiation. However, the results of the analysis indicated that the absorbed solar radiation is reduced due to the high albedo of snow and therefore cannot compensate for the heat loss by long-wave radiation. This occurrence results in negative net radiation during winter. To evaluate the heat balance on road snow, the infrared radiation from vehicles was estimated by measuring vehicle temperatures. These measurements indicated that heat input applied to snow decreased with vehicle speed and increased with traffic volume. A new index—the shading time—was developed and is defined as the amount of time a section of road is shadowed by vehicles. It was established that incoming long-wave radiation increased by 50 percent during 20 minutes of shading time and that the net radiation became positive, suggesting that snow melting occurred on roads with heavy traffic flow, even in winter.