Variation of tree crown height effects on flow behavior around finite vegetation
Variation of tree crown height effects on flow behavior around finite vegetation
复制标题
树冠高度变化对有限植被周围流动行为的影响
DOI：
10.1080/23249676.2022.2110165
复制
发表时间：
2022
影响因子：
1.2
通讯作者：
N. Tanaka
中科院分区：
文献类型：
--
作者：
Amina;N. Tanaka
先前已经研究了长形植被仅利用树木结构的树干部分来抵抗海啸的能力。然而，调查植被的恢复力，同时考虑到树冠部分是未知的。利用有限植被模型（EVM），研究了树冠高度变化对植被与其周围林隙之间的水流结构行为的影响。实验变量包括，如树冠高度（其中是从地面的冠高，是总树高），植被的宽度与长度比（W/L），和初始弗劳德数的条件，其范围在0.67和0.76之间。结果表明，当植被宽长比较小时，冠高比（< 0.3）与无冠（NC）和最高冠高比（> 0.3）相比，显著降低了植被斑块区后的流速和流体力。另一方面，与NC相比，小植被斑块中的冠状壳的影响并没有增加差距区域的速度和流体力。而随着冠高比的减小（< 0.4），植被片沿着宽度的增加，植被片后的流速和流体力进一步减小，但随着冠高比的减小，植被片宽度的增加，周围间隙区域的流速和流体力增加。
Finite-length vegetation has been previously studied for its ability to provide resistance against the tsunami by using just the trunk section of the tree stand structures. However, investigating the resilience of the vegetation while taking the crown section into account is yet unknown. Using a limited emergent vegetation model (EVM), this research examined the impact of changing the tree crown heights on the flow structure behavior between the vegetation and its surrounding gap region. Experimental variables included such as tree crown height ( in which is the crown height from the ground surface and is the total tree height), vegetation width to length ratio (W/L), and the initial Froude number condition , which ranged between 0.67 and 0.76. The outcomes demonstrated that, when the vegetation width to length ratio was small, the crown height ratio ( < 0.3) significantly reduced the velocity and fluid force behind the vegetation patch region as compared to no crown (NC) and highest crown height ratio ( > 0.3). On the other hand, the effect of crown cases in the small vegetation patch did not increase the velocity and fluid force in the gap region in comparison with NC. Whereas the increased width of the vegetation patch along with the lower crown height ratio ( < 0.4) further decreased the velocity and fluid force behind the vegetation patch but the increased width of the vegetation patch in combination with the lower crown height ratio increased the velocity and fluid force in the surrounding gap region as compared to its NC case.