轻小型平移式喷灌机研制及其稳定性分析与试验

发布时间：2018-07-23 13:29

【摘要】：随着水资源短缺与社会发展之间矛盾凸显的今天,大力发展节水灌溉是解决我国水资源短缺的根本出路。针对目前国内外喷灌机组的发展中存在的适应性差、设备复杂、结构笨重等问题,研制出一种新型轻小型平移式喷灌机。本文通过对其结构的理论分析、强度计算以及与动力学建模仿真相结合的方法,对自制的轻小型平移式喷灌机进行结构设计并讨论其在不同坡道的通过稳定性。在特定试验条件下对喷灌机组的水力性能进行试验。主要研究内容包括以下几个方面:(1)对自行研制的平移式喷灌机的关键部件的设计,使得喷灌机具有易拆卸、喷头安装高度与间距可调的特点。通过对洒水车的关键部件的受力理论分析,提出提高构件结构强度的方法;对喷灌机自动控制的要求提出简单、方便的控制方法。(2)对轻小型喷灌机在坡地的通过稳定性进行理论受力分析,提出了影响轻小型平移式喷灌机爬坡能力的因素,其中包括机组轮距、质心高度以及附着系数。结果表明:在纵向坡道上匀速行驶,机组前后轮距为3m,质心高度为3.37m时,机组不发生翻倾的极限坡度角约为26°。在湿土路的附着系数为0.5~0.7的条件下,最大滑移角度t为31°。(3)对轻小型平移式喷灌机进行多体动力学建模仿真。运用多体动力学仿真软件ADAMS对该机组进行动力学建模,让建立的整机模型在2D水平路面与不同坡道上分别进行整车通过性能分析,并通过传感器检测质心高度的变化情况。结果表明:该新型喷灌机整车的最大爬坡角度小于等于25°时,能够顺利完成仿真,在大于25°时,机组发生侧倾不能正常工作。同时,运用虚拟样机技术对整机进行仿真与计算,为以后喷灌机组的研发与推广使用提供了一种高效的试验方法。(4)新型平移式喷灌机的喷头在特定的安装高度、安装间距、工作压力下进行水力性能试验;对机组灌水量的影响因子进行单因素方差分析与最小二乘法非线性回归分析,同时对影响其灌水量的主要因素之间进行定量分析。结果表明:在喷头组合间距为3m,安装高度为1m,工作压力为0.07MPa与0.14MPa下,组合喷灌均匀系数均超过了85%,分布均匀性系数也达到了80%。机组运行距离与工作压力对灌水量影响的显著性概率分别为0.74和0.08,运行速度比对灌水量的显著性概率为8.2e-7。
[Abstract]:With the contradiction between water resources shortage and social development prominent today, developing water saving irrigation is the fundamental way to solve water shortage in China. In view of the problems existing in the development of sprinkler irrigation units at home and abroad, such as poor adaptability, complex equipment and heavy structure, a new type of light and small translational sprinkler irrigation machine has been developed. Based on the theoretical analysis, strength calculation and dynamic modeling and simulation of its structure, this paper designs the structure of the self-made light and small translational sprinkler irrigation machine and discusses its stability in different ramps. The hydraulic performance of sprinkler irrigation unit was tested under certain test conditions. The main research contents include the following aspects: (1) the design of the key parts of the self-developed translation type sprinkler irrigation machine makes the sprinkler machine easy to disassemble and the installation height and spacing of the sprinkler head can be adjusted. Based on the analysis of the stress theory of the key parts of the sprinkler, the method of improving the structural strength of the member is put forward, and the requirement of automatic control of the sprinkler is put forward. (2) the theoretical analysis of the stability of the light and small sprinkler irrigation machine on the slope is carried out, and the factors affecting the climbing ability of the light and small translational irrigation machine are put forward, including the wheel spacing, the height of the center of mass and the adhesion coefficient. The results show that the ultimate slope angle of the unit without overturning is about 26 掳when the wheel distance is 3 m and the height of the center of mass is 3.37 m on the longitudinal ramp. The maximum slip angle t is 31 掳under the condition that the adhesion coefficient of wet soil road is 0.5 ~ 0.7. (3) Multi-body dynamics modeling and simulation of light and small translational sprinkler irrigation machine is carried out. The dynamic modeling of the unit is carried out by using the multi-body dynamics simulation software ADAMS, and the vehicle performance analysis is carried out on 2D horizontal road surface and different ramps, and the change of the height of the center of mass is detected by the sensor. The results show that when the maximum angle of climbing is less than or equal to 25 掳, the simulation can be completed successfully, and when the maximum angle of climbing is less than 25 掳, the unit can not work normally when it is larger than 25 掳. At the same time, the virtual prototyping technology is used to simulate and calculate the whole machine, which provides an efficient test method for the later research and development and popularization of the sprinkler group. (4) the nozzle of the new type of translational sprinkler irrigation machine is installed at the specific installation height and the installation distance. Hydraulic performance test was carried out under working pressure, single factor variance analysis and least square nonlinear regression analysis were carried out on the influencing factors of the water quantity of the unit, and quantitative analysis was carried out among the main factors affecting the irrigation quantity. The results show that when the combined nozzle spacing is 3 m, the installation height is 1 m, and the working pressure is 0.07MPa and 0.14MPa, the uniform coefficient of combined sprinkler irrigation exceeds 85 and the distribution uniformity coefficient reaches 80. The significant probability of the influence of the operating distance and the working pressure on the irrigation quantity is 0.74 and 0.08 respectively, and the significant probability of the ratio of running speed to the irrigation quantity is 8.2 e-7.
【学位授予单位】：江苏大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S277.94

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