摘要
船式拖拉机是深泥脚水田耕整作业的新型拖拉机,其船壳阻力是影响性能的重要因素。为此,通过测量水田土壤流变特性、简化实际的船体结构,考虑空气、水、泥浆3种介质,构建船式拖拉机船体多相流数值仿真模型,研究了工况速度与船体粘性阻力、兴波性能之间的关系及水层的减阻性能,并开展船模实验。结果表明:船底不完全满足动压润滑条件,导致水层减阻效果不明显,在船体底部安装侧挡板的方法可以提高动压润滑的能力,降低船体行驶阻力。
The ship type tractor is a new type of tractor which is used in deep mud foot water field,the hull resistance is an important factor affecting performance.In this paper,by measuring the rheological properties of paddy soil,simplifying the actual hull structure,and considering air,water and mud,a numerical simulation model of ship tractor hull multiphase flow is constructed. The relationship between the working condition velocity and the ship's viscous resistance and wave-making performance is studied,The anti-drag performance of water layer is studied and ship model experiment is carried out.It is concluded that the bottom of the ship does not fully meet the dynamic pressure lubrication condition,resulting in the inconspicuous anti-friction effect of water layer.
引文
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