栅栏最佳疏透度的空气动力学评价

摘要/Abstract

摘要： 为研究栅栏防沙的动力学机制,运用风洞中PIV所测风速资料,从空气动力学角度对直立栅栏的最佳疏透度范围进行了讨论与评价。结果表明,不同研究者所得栅栏的最佳疏透度范围不尽相同,大致范围在0.2～0.6之间,结果非常分散。PIV资料评价的栅栏最佳疏透度在0.2～0.3之间,该疏透度范围的栅栏周围气流湍流度较低,对风能的耗散较大,能有效抑制过境风沙流,理论上属于防沙的最佳疏透度,但实践操作中为了降低成本,阻沙栅栏的实际疏透度可适度增大,放宽到0.3~0.4左右。栅栏绕流的复杂性,使得众多研究都运用了过多的简化与假设,而且研究者们对于栅栏防护过程的不同理解以及所强调的保护侧重点不同导致评判的标准也各不相同,最终得到的最佳疏透度范围也有所差异。

关键词: 阻沙栅栏, 最佳疏透度, PIV, 空气动力学评价

Abstract: In order to study the dynamical mechanism of sand fences sheltering effect, the optimal porosity of fences was discussed and evaluated from aerodynamic angle and based on the measured velocity data by PIV technology in the wind tunnel. Although the ranges of the optimal fence porosity are diversified among different research results, most ranging between 0.2~0.6, the reevaluated optimal fences porosity by PIV technology is 0.2~0.3. Fences with this range of porosity (between 0.2 and 0.3) have lower turbulence intensity in the leeside, the larger dissipation of wind energy, which can effectively controlled sand current. This belongs to the optimal fence porosity in theory, however, the fence porosity can always be broaden to 0.3~0.4 in practice to reduce its cost and without significant expense of shelter efficiency. Nevertheless, the complexity of flow over sand fences made the research of this problem use more simplification and hypothesis usually. Furthermore, peoples different comprehension and emphases on fences' sheltering degree made the standard of judges to be different, which led to the variety of optimal porosity of sand fences reported by investigators.

Key words: upright sand fences, optimal porosity, PIV, aerodynamic evaluation

中图分类号:

X169

罗万银;董治宝;钱广强. 栅栏最佳疏透度的空气动力学评价[J]. 中国沙漠, 2009, 29(4): 583-588.

LUO Wan-yin;DONG Zhi-bao;QIAN Guang-qiang. Aerodynamic Evaluation of the Optimal Porosity of Sand Fences[J]. JOURNAL OF DESERT RESEARCH, 2009, 29(4): 583-588.

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