多通道自动集沙仪优化设计与试验研究

发布时间：2019-05-18 02:51

【摘要】：土壤风蚀是土壤在风力作用下剥蚀、分选、搬运的过程,是干旱、半干旱地区面临的一个重大环境问题,土壤风蚀会导致土壤质地变粗,结构变坏。集沙仪是一种研究农田土壤风蚀的重要装置,是观测风沙流结构和研究风沙运动规律的关键设备,为获得大量而精确的风蚀数据,需要不断地对集沙仪进行创新和优化设计。以FLUENT软件和微型风洞为试验平台,对分流对冲式多通道自动集沙仪风沙分离器的排气管直径、排气管长度、排沙口直径、排沙口收缩高度进行了优化设计。数值模拟和风洞试验的结果显示:改进型风沙分离器排气口和排沙口的降速性能与原风沙分离器相比有了明显的提高,强风条件(13.8m/s)下排气管直径为25mm、排气管长度为25mm、排沙口直径为75mm、排沙口收缩高度为15mm时,气流对集沙仪自动采集传感器的冲击力最小,排气口最高风速为2.23m/s,比原风沙分离器降低了 7.47%,平均风速为0.68m/s,比原风沙分离器降低了 8.11%,排沙口最高风速为1.52m/s,比原风沙分离器降低了 35.59%,平均风速为0.23m/s,比原风沙分离器降低了 28.13%,气固分离效率平均值为99.82%,与原风沙分离器相比略有提高,大约提高了 0.02%。在满足等动力性、高效率性和非选择性三条基本原则下,对多通道自动集沙仪的导向板,集沙仪外壳,旋转装置,集沙仪支架,集沙单体进行了优化设计,并对集沙仪的降速和集沙性能进行了试验验证。结果表明,优化后的多通道自动集沙仪具有较好的降速性能和集沙性能,平均集沙效率为91.98%,等动力性为92.06%,在野外环境中工作情况良好。
[Abstract]:Soil wind erosion is the process of soil denudation, sorting and transportation under the action of wind. It is a major environmental problem in arid and semi-arid areas. Soil wind erosion will lead to thicker soil texture and worse structure. Sand collector is an important device to study soil wind erosion in farmland. It is the key equipment to observe the structure of wind sand flow and study the movement law of wind sand. In order to obtain a large number of accurate wind erosion data, it is necessary to continuously innovate and optimize the design of sand collector. Using FLUENT software and micro wind tunnel as the test platform, the diameter of exhaust pipe, the length of exhaust pipe, the diameter of sand outlet and the shrinkage height of sand outlet are optimized. The results of numerical simulation and wind tunnel test show that the speed reduction performance of the improved air sand separator outlet and sand outlet is obviously improved compared with the original air sand separator, and the diameter of the exhaust pipe is 25mm under strong wind condition (13.8m/s). When the length of exhaust pipe is 25mm, the diameter of sand outlet is 75mm, and the shrinkage height of sand outlet is 15mm, the impact force of air flow on the automatic acquisition sensor of sand collector is the smallest, and the maximum wind speed of exhaust port is 2.23m / s, which is 7.47% lower than that of the original wind and sand separator. The average wind speed is 0.68 m / s, which is 8.11% lower than that of the original wind and sand separator, and the maximum wind speed of the sand outlet is 1.52 m / s, 35.59% lower than that of the original wind sand separator, and the average wind speed is 0.23 m / s. Compared with the original wind-sand separator, the average gas-solid separation efficiency is 99.82%, which is slightly higher than that of the original wind-sand separator, which is about 0.02% higher than that of the original wind-sand separator. Under the three basic principles of isodynamic, high efficiency and non-selectivity, the guide plate, sand collector shell, rotating device, sand collector support and sand collecting monomer of the multi-channel automatic sand collector are optimized. The speed reduction and sediment collecting performance of the sand collector are verified by experiments. The results show that the optimized multi-channel automatic sediment collector has good speed reduction performance and sediment collection performance, the average sediment collection efficiency is 91.98%, the isodynamic performance is 92.06%, and the working condition is good in the field environment.
【学位授予单位】：内蒙古农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S157;S237

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