新型农田风蚀集沙仪排沙口降速问题研究

农田土壤风蚀会导致土壤质量退化,甚至出现荒漠化。防止农田土壤退化,研究其风蚀机理是关键,而集沙仪是研究土壤风蚀的必需仪器。随着自动控制理论在各行业的广泛应用,为集沙仪配备自动采集系统是一个发展趋势。由于集沙仪排沙口气流对称重天平的冲击是引起数据波动的主要来源,所以降低集沙仪排沙口气流速度是很关键的。为此,提出了设计一台新型农田风蚀集沙仪以解决排沙口降速问题的新思路。首先,阐述了新型农田集沙仪的设计原理;随后,通过数值模拟方法对其关键部件风沙分离器进行了数值模拟,得出了其内部速度矢量场模拟图;最后,通过烟流试验和风洞试验对数值模拟结果进行了验证。结果表明:数值模拟结果是可靠的;当新型农田集沙仪受强风环境影响时,其排沙口气流的降速幅度达84%,可较好地缓解排沙口气流对称重天平的冲击。该研究也可为新型农田集沙仪的后续研究提供理论支持。

Study on the Deceleration Issue of a New Sand Sampler for Farmland Erosion

Farmland soil erosion would lead to degradation of soil quality , even desertification , preventing degradation of farmland soil , the key was to study the erosion mechanism ,a sand sampler was the essential equipment .With the auto-matic control theory was widely used in various industries ,Equiping a sand sampler with automatic collection system was a trend, Due to the attacking of flushing-port flow on weighing scales was the main source of data fluctuations caused ,so it was the critical to reduce flushing-port flow rate .For this reason , this paper proposed a new way to resolve a flushing-port deceleration problem though designing a new sand sampler for farmland erosion .First,expounding the design prin-ciples of a new sand sampler for farmland erosion ,then carryed out a numerical simulation on a wind-sand separator that was its key part , obtained a drawing simulation of its internal velocity vector , Finally ,carried out a test verify on the sim-ulation results though a smoke flow test and a wind tunnel test .The conclusion was that the simulation results were relia-ble.When a new sand sampler for farmland erosion affected by windy conditions , spin-down rate of flushing-port flow was up to 84%,could better alleviate the attacking of flushing-port flow on weighing scales,This study also provided theoretical support for the new follow-up study on a new sand sampler for farmland erosion .