发布时间：2015-09-05

文章标题：【学术成果】一篇第一作者文章在国际学术期刊Sedimentology上发表

内容：

http://onlinelibrary.wiley.com/doi/10.1111/sed.12232/full

ABSTRACT

The characterisation of aeolian sand creep motion remains incomplete. In this study, a top-view imaging system was constructed in a wind tunnel experiment to record sand creep motion on a flat sand bed. In addition, a set of ‘mesoscopic’ parameters was defined based on the creep trajectory that was reconstructed by a particle tracking algorithm. Statistical results show that the parameters representing the lifespan of the creep motion follow a lognormal distribution, whereas those representing the sideways grain motion deviate from the lognormal distribution. As the wind velocity increases, the sideways motion is strengthened and the lifespan of the creep motion is shortened, indicating a stronger transition from creep to saltation. Furthermore, under a ‘pure rolling’ hypothesis, the creep trajectory can be transformed into two numbers of rolling cycles from the perspectives of space and time. The ratio of the two numbers is useful in identifying the specific mode of the creep motion.

Keywords: sand creep motion, wind tunnel experiment, particle tracking, creep trajectory, mesoscopic parameter