新型主动式竖直集沙仪研制

提出了一种新型主动式竖直集沙仪，该集沙仪的最大优点是可以通过调节总抽气量使不同高度取样管同时趋于等动力取样状态．对新型集沙仪和传统被动集沙仪进行了风洞对比实验，并引入一个新的量来反映集沙仪对气流的阻碍程度．实验结果显示，新型集沙仪对气流的阻碍明显减小，在不同风速下也具有很好的适应性．输沙率对比结果表明，新型集沙仪比传统被动集沙仪在近床面区域和高风速下具有更高的收集效率，为风沙流研究提供了一种新的测量工具．

Development of a New Type of Active Vertical Sand Trap

A new active vertical sand trap is designed to implement the performance that airflows in all sampling tubes at different height are allowed simultaneously approach to the isokinetic state. The comparative experiments of the new active sand trap with a traditional passive one are carried out in a wind tunnel, where a new non-dimensional parameter is introduced to evaluate the stagnant effect on airflow of the trap. The results indicate that the new sand trap is able to remarkably reduce the stagnant effect with fine adaptability under different wind conditions, and the vertical mass flux measurements verify the higher efficiency of the new trap, especially in high speed wind and near bed region.