防风网作用效果的风洞实验评估

Evaluation on Shelter Effect of Porous Windbreak Fence through Wind Tunnel Test

以某钢铁集团即将建设的大型堆料场为背景,运用平面风速传感器和丝线流动显示方法对料场防风网的作用效果进行了评估,得到了料场在3个主导风向下的基本流动形态。实验结果表明建设防风网将使来流风速明显降低,最多可达80%。但由于开孔率偏低,在料场内部会造成大尺度的涡结构。因此有必要对防风网的设计做进一步的优化。本文结果同时也说明由于地形等因素的影响,防风网的实际效果应结合堆料场的具体条件进行讨论。

The flow field of a large storage yard with windbreak was investigated in the wind tunnel under three dominant wind directions. The wind speed was measured by the so-called ＂omnidirectional surface wind sensor＂, and the qualitative flow pattern was visualized by tuft method. According to the experimental results, the shelter effect of the porous windbreak fence was evaluated. It was found that the wind speed significantly decreased behind the windbreak, by 80% at most. However, at some wind direction a large bubble appeared behind the fence due to the low porosity of 30%. Thus it＇s necessary to improve the design of the windbreak fence. In addition, it was verified that the shelter effect for a certain storage yard was related to the local terrain and accordingly the given conditions should be taken in consideration.