蝼蛄前足爪趾三维几何构形的减阻机理  

Drag reduction mechanism of the 3D geometry of foreleg’s claw toe of the mole cricket(Gryllotalpa orientalis)

作　　者：张琰 乔超雄[1,2] 王天琪 曹佳丰 王鹏飞 石磊 Zhang Yan;Qiao Chaoxiong;Wang Tianqi;Cao Jiafeng;Wang Pengfei;Shi Lei(Tianjin Key Laboratory of Integrated Design and On-line Monitoring for Light Industry&Food Machinery and Equipment,Tianjin 300222,China;College of Mechanical Engineering,Tianjin University of Science&Technology,Tianjin 300222,China;Tianjin Limin Condiment Co.,Ltd.,Tianjin 300308,China)

机构地区：[1]天津市轻工与食品工程机械装备集成设计与在线监控重点实验室,天津300222 [2]天津科技大学机械工程学院,天津300222 [3]天津市利民调料有限公司,天津300308

出　　处：《农业工程学报》2021年第19期309-315,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(51405341);天津市自然科学基金(15JCYBJC19300);天津市重点实验室开放基金(2019LIMFE05)。

摘　　要：触土部件的阻力直接影响耕作机械和工程机械的作业效率,该研究利用工程仿生设计方法,基于蝼蛄前足爪趾优异的地下掘进能力,提取前足爪趾的三维几何构形特征用于仿生试件设计,通过土槽切削阻力试验和有限元模拟,分析蝼蛄前足爪趾几何构形的减阻性能和机理。研究结果表明,前足爪趾的构形特征对切削阻力有显著影响(P<0.05),仿生试件的切削阻力较楔状体试件最高可降低56.96%,三维仿生构形的减阻性能优于一维和二维构形。蝼蛄前足爪趾构形能使被切削土壤沿挖掘面顺畅移动,避免了土壤在仿生试件尖部的堆积和对中后部的挤压,实现切削阻力的减小。该基于蝼蛄前足爪趾的工程仿生研究可为耕作和工程机械触土部件的减阻设计提供理论基础。Biological plane geometry has been unable to meet the harsh requirements of bionic design in most soil contacting parts of tillage machinery in recent years, particularly on the operating speed, energy-saving, and emission reduction. In this study, a bionic investigation was performed on the toe of the foreleg claw in the mole cricket using the three-dimensional(3D)geometry. Projection and segmentation were also used to extract the 3D characteristic curves of claw toe in three orthogonal planes. The MATLAB platform was selected to determine the characteristic curves via the polynomial fitting and smoothing processing. An orthogonal experiment of bionic samples was carried out, where three plane configurations were taken as factors, while the different characteristics of configuration as levels. A total of 16 bionic specimens and 1 wedge-shaped comparison specimen were constructed by SolidWorks software and then fabricated using 3D printing(polylactic acid material). A test system of soil groove was utilized to evaluate the cutting resistance of each specimen, where the soil was assumed as the foamed phenolic plastics, the cutting speed was 10 mm/s, the cutting depth was 15 mm, and the cutting time was 20 s. The explicit dynamic Finite Element(FE) software ANSYS LS-DYNA was used to simulate the cutting process of the specimen, in order to determine the relationship between the 3D geometrical toes of the foreleg claw in the mole cricket and the drag reduction performance. It was found that the cutting process of the specimen was divided into the drag increase and stable phase. Furthermore, the drag reduction performance of specimens with 3D biological geometries was significantly better than that with one-and two-dimension, as well as the wedge shape. All configurations in the three planes also presented a significant impact on drag reduction. Correspondingly, the main influencing factor of drag reduction was the cross-sectional configuration perpendicular to the growth direction of claw toes. More importantly, the

关 键 词：农业机械 仿生 设计 优化 减阻 切削阻力试验 蝼蛄 

分 类 号：S220.1[农业科学—农业机械化工程]