通过分析近年来国内外集沙仪的研究成果,确定了影响集沙仪集沙效率的主要结构参数:集沙仪进沙口的高宽比、进沙通道长度、布袋材质等。根据集沙仪性能试验要求,对不同结构参数的集沙仪进行了风洞性能试验。试验结果表明:在6、9、12、15、18m/s5个风速下,集沙仪对0.15~0.60mm粒径土样的平均集沙效率高于混合土样和0.15mm以下粒径土样的平均集沙效率,说明集沙仪更适合采集以跃移形式运动的土壤颗粒。结构因素对集沙效率影响的主次顺序为进沙口高宽比、进沙通道长度、布袋材质。进沙口高宽比是对集沙效率影响显著的结构因素。通过对试验结果的极差和方差分析,得出集沙仪最优组合的结构参数是高宽比为0.5、进沙通道长度为20cm、白丝布,此时集沙仪的平均集沙效率为80.91%。
By analyzing the research results of scholars overseas and domestic in recent years,the main structural factors which impact sampling efficiency were ascertained. They are the ratio of inlet height to width,the channel length,and material of hop-pocket. According to the sand sampler for performance test requirements,different construction parameter sand samplers were designed and tested in the wind erosion tunnel. The results indicate that the average sampling efficiency to soil particles of 0.15-0.60 mm is higher than intermixed dust and 0.15 mm under 6,9,12,15,18 m/s wind speed. The sampler is applicable to the acquisition of soil particles with the form of jump movement. The order of structural factors that affect sampling efficiency is the ratio of inlet height to width,the channel length,and material of hop-pocket. And the ratio of inlet height to width is the most remarkably factor. By the variance and range analysis,the optimization structure parameter of the sand sampler is as follows:the ratio of inlet height to width is 0.5,the channel length is 20 cm and the material of hop-pocket is falda. Under this situation,the average sampling efficiency of the sand sampler is 80.91%.