Range of the Applicability of the Wilkins Method to the Investigation of the Dynamic Stress-Strain State of Anisotropic Elastic Axisymmetric Shells

The exactness and stability of the Wilkins method in the investigation of the stress-strain state of axisymmetric anisotropic elastic shells, including thick-walled ones, have been studied for different values of artificial viscosity, pulse load rise and fall time, and different deformation process durations. A comparison of numerical calculations, performed by means of an application software package developed by V. A. Romashchenko on the basis of the Wilkins method, with experimental results, known numerical data, and with calculations using the computation kernel LS-DYNA 3D has been carried out.     

Efficient modeling of panel-like structures in perforation simulations

This paper presents results of numerical simulations for impact effects in panel-like structures using solid and shell element modeling techniques. Three examples from experiments in literature have been numerically analyzed. The nonlinear transient dynamic analysis code, LS-DYNA is used in the simulations to model projectiles and panel-like targets. It is found that models established for panel-like targets using solid shell elements cannot only save significant computational effort, but also produce good results as long as the panel-like targets satisfy certain conditions. A criterion that governs the validity of modeling panel-like targets with shell elements is proposed in the paper.     

Numerical Simulation of Deforming Manufacture Process for Automobile Bevel Gear Blank

1 Introduction Rear axle bevel gearis a vital kind of annular accessory with high precision and hugeload availablefeatures ,andit is widely used as the differential drive in automobiles and tractor .In China ,the traditional manufactureapproach of producing the rear axle bevel gear blankis die forging,which not only requires a highinvestment ofproduct equipments , but also involves a low material utilization and great noise .In order to overcome thesedrawbacks , manyresearchers have done a gre…     

预控破片形成过程的数值模拟与分析

为了获得预控破片战斗部破片的飞散规律,利用ANSYS／LS-DYNA有限元软件对某榴弹壳体膨胀和破片破碎过程进行数值模拟,得到破片初速和飞散方向角沿弹轴曲线分布,与破碎性试验回收破片的统计结果和经验公式都基本一致,这说明模型简化及计算参数的正确性．     

用LS-DYNA模拟柱状弹丸侵彻薄钢板过程

根据破片模拟弹侵彻钢板的理论研究,采用ANSYSLS—DYNA对破片模拟弹侵彻钢装甲的侵彻过程、钢板的破坏模式以及弹体的侵彻速度进行有限元分析,并将分析结果与理论结果进行比较．分析结果表明,有限元分析的破片模拟弹侵彻特性及刚装甲破坏模式与理论结果有较好的一致性,讨论了弹丸侵彻装甲的作用过程,有限元分析结果表明,采用适当的模型,有限元法能较好地模拟破片模拟弹侵彻钢板的侵彻过程、侵彻特性以及钢板的破坏模式．     

海浪对导弹出水姿态影响数值分析

基于LS-DYNA有限元软件建立了导弹出水过程的有限元模型,应用数值仿真方法分析了海浪对导弹出水姿态的影响,获取了导弹在不同海浪等级条件下出水姿态的变化规律,为获取极限海浪等级对导弹出水姿态影响的运动规律,提供了有效的数值仿真手段。     

城镇闹市区地铁车站基坑的控制爆破?

为确保某市地铁车站基坑爆破的成功实施,以爆破危害和块度控制为重点内容,通过优化爆破设计,综合采取多种安全有效、经济环保的防护措施,成功将爆破施工过程中的安全危害(爆破振动、飞石、有害气体、外来电流等)和环境危害(爆破噪音、粉尘等)控制在许可范围内;同时,运用LS-DYNA模拟岩石破碎效果,成功控制了大块率。实际爆破效果符合预期,工程效益显著。     

益新矿中心大空孔掏槽爆破扩腔过程数值分析

为了更好的应用中心大空孔掏槽爆破技术,根据益新煤矿爆破工况,运用有限元软件LS-DYNA,深入分析爆破过程中应力波的传播、有效应力和应力场的变化,研究其扩腔过程及岩石破碎机理。结果表明:爆炸应力波首先在炮孔连线方向相遇叠加并形成一条直线型的加强带,然后传至空孔并发生复杂的反射和叠加,最后在岩体中扩散;空孔外围的应力场分布呈现"圆形-菱形-圆形-方形"的变化规律;中心大空孔掏槽爆破有利于炸药能量的均匀分布和槽腔的形成与扩展。现场验证表明:该项技术大大提高了煤矿巷道的掘进速度,取得了较好的经济效益。     

基于ANSYS/LS-DYNA的返回舱海面撞水动力研究

在理论分析刚形体垂直撞水动力特性的基础上,分别推导出基于von Karman理论和通用Wagner理论的圆球底返回舱撞水冲击过载公式.然后借助ANSYS/LS-DYNA动力显式程序中ALE算法的优势,进行返回舱海向垂直撞水动力数值仿真;针对数值仿真结果和理论分析预报结果的比较分析来验证数值仿真的可行性,同时给出数值计算弹性体模型垂直撞水的撞水冲击过载;结果表明:采用ANSYS/LS-DYNA的ALE算法可以有效地数值模拟返回舱撞水动力特性,为进一步控制返回舱海面回收以及数值分析撞水动力特性提供有力的技术支持,且大大节约了试验经费.     

热连轧圆钢成品孔型的有限元分析

根据ф16 mm圆钢的轧制规程,运用有限元分析软件ANSYS中的LS-DYNA大变形弹塑性显式分析动力学模块,对终轧机架在分别采用双半径圆弧和切线扩张角两种成品孔型条件下的热连轧过程进行有限元模拟。对比分析了同一轧件在不同孔型中的金属流动特性和应力应变分布规律。结果表明,有限元模拟结果与实际生产过程相吻合;对同样采用30°扩张角的两种孔型而言,轧件在双半径圆弧成品孔型中的表面受力和总体应变分布更为均匀;轧件在成品孔型的圆弧扩张部位受到的应力较大,使轧辊轧槽表面磨损不均;采用材质硬度更高的成品轧辊,可以降低轧槽表面的磨损程度,延长轧辊孔型的使用寿命,节约生产成本。