基于LS-DYNA的枝条锯切过程研究

Research on sawing process of hedge branches based on LS-DYNA

圆锯片在锯切绿篱枝条的过程中,需要保持高速旋转且会发生复杂变形,常规方法很难对锯切过程中圆锯片和绿篱枝条之间的相互作用进行观察和分析。为了能够安全获得锯切过程中圆锯片瞬态变形和受力,更加细致地研究其锯切机理,尝试采用有限元法进行研究。在ANSYS/LS-DYNA模块中对锯切过程进行显式动力学模拟,可以清晰观察整个锯切过程并得到圆锯片受力大小随时间的变化图像,与实验数据对比的误差未超过5%。对圆锯片齿尖上一点的位移进行测量,x、y方向的位移变化规律符合圆锯片的运动情况,z方向的最大振幅不足1 mm,说明在锯切过程中圆锯片的动态稳定性较好。对整个过程的研究表明,利用LS-DYNA对圆锯片锯切枝条过程进行显式动力学模拟,可以克服常规方法的不足,清晰地展现整个锯切过程,并得到每个时刻的圆锯片受力及变形情况,对今后的相关研究提供了一种有效途径。

In the process of cutting branches of a hedge, the circular saw blades rotate at a high speed and will deform. It is difficult to observe and analyze interactions between circular saw blade and hedge branches in the cutting process by conventional methods. The finite element method was chosen to study the details of the sawing mechanism and to the transient deformation and stress of the saw blade safely. By dynamics simulations of the cutting process in the ANSYS/LS-DYNA module, the cutting process was clearly observed and the force of the circular saw blades change over time was showed. Error of the force compared with the experimental data does not exceed 5%. By measuring the displacement of a point on the circular saw blade sharp it was showed that the displacement variations of x, y direction complies with the movement of circular saw. The maximum amplitude of z direction is less than 1 mm, suggesting that the dynamic stability of the sawing process is good. This research shows that the dynamic simulation of cutting process by using LS-DYNA could overcome the deficiencies of conventional methods, the whole cutting process can be revealed showed, and the force arid deformation of the circular saw blades of each time can be obtained. This work can serve as a reference for the related research in the future.