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由于传统的轴对称和平面对称聚能装药切割器应用的局限性,本文根据Birkhoff经典的射流理论以及数值模拟结果,从理论上对聚能圆形切割器进行了研究,提出了一种理想的设计方法,讨论了影响聚能效果的基本参数,得到了药型罩壁厚与顶角、装药半径之间的关系,为圆形切割器的研究有较大的参考价值. 相似文献
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在简述环爆切割器的工作原理的同时,提出了环状聚能切割的设计方法,并着重对环状药型罩的结构、制作工艺以及参数确定作了说明,还提供环爆切割器在水下进行了爆破威力的验证. 相似文献
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利用ANSYS/LS-DYNA有限元大型工程分析软件,对某军用战斗部线型聚能装药切割器进行聚能装药射流形成、侵彻靶板过程的数值仿真,得到与试验结果相近的聚能射流形成和侵彻的物理现象和规律,侵彻深度误差为8.74%,验证了该模型和数值算法的合理性。在战斗部的设计中有一定借鉴意义。 相似文献
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往复式切割器切割图的计算机辅助分析 总被引:3,自引:0,他引:3
切割器是收获机械中重要的组成部件,其性能的好坏直接影响收割机的效率。在切割器设计过程中,对切割图的研究又尤为重要,因此利用VB开发了一个操作界面简单、交互功能强的往复式切割器切割图分析软件,通过计算机辅助分析,对切割器进行研究,避免了参数改变后对切割图的重新绘制。研究结果表明往复式切割器切割图的计算机辅助分析能为切割器的设计提供可靠的参数分析,减轻设计人员的劳动强度,提高设计效率。 相似文献
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线型聚能装药切割钢板过程的数值模拟 总被引:1,自引:0,他引:1
利用ANSYS/LS—DYNA对线型聚能装药射流的形成和侵彻铜板过程进行数值模拟,并对切割效果加以考察。通过其结果说明,数值模拟方法可用于聚能装药的优化设计和切割其他材料的研究。 相似文献
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In the present paper, in the framework of the three-dimensional linearized theory of stability the rotationally symmetric stability loss problems of the elastic and viscoelastic composite rotating thick circular and annular discs are investigated. The method for solution to these problems is developed by employing Laplace transform and finite element method. It is supposed that the disc and annular disc have an insignificant rotationally symmetric initial imperfection and as a stability loss criterion, the case where this imperfection starts to increase and grows indefinitely, is taken. Numerical results related to the critical angular velocity for elastic problems and to the critical time for viscoelastic problems are presented. 相似文献
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The stiction force strongly depends on the bump parameters. Numerical simulation has been used to estimate the stiction force. Several schemes have been proposed. In these schemes, the relation between the elastic deformation of bumps and the load plays a very important part. To estimate the stiction force of annular shaped bumps, the solution of the cylindrical contact problem of Hertz theory is used. But this solution doesn't converge so that it may not give the correct solution for the annular contact problem. This paper presents an exact solution of elastic deformation of laser textured bumps for the annular type. The exact and precise solution is obtained numerically and analytically. The contact problem is reduced to a pair of integral equations of the Fredholm type. It can be solved by a simple numerical method. The solution can be used for the numerical estimation of the bump deformation during the CSS process. The results are compared with former researches. 相似文献
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车削切削力不确定性的模糊—灰色预测 总被引:2,自引:0,他引:2
为了定量预测车削力的不确定性范围 ,基于对称模糊数、线性规划理论和灰色理论 ,提出了一种切削力不确定性的模糊—灰色预测方法 ,建立了用于获取评价数据的车削力测量系统以验证该方法的有效性。预测与实测结果的对比分析表明 :对于给定的切削条件 ,预测值是可变力的一个范围 ,而不是用传统方法所得的一个确定点 ,实测力以较小的相对误差落在预测范围内 相似文献
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镍基高温合金工件异形孔加工工艺的研究 总被引:2,自引:0,他引:2
根据航空发动机涡轮盘上异形孔结构复杂及镍基高温合金材料难加工的特点 ,采用钻削、铣削与磨削工艺的不同组合、选用新型涂层刀具和相应的切削参数进行了工艺试验。通过分析试验过程中刀具、砂轮的磨损(破损 )情况及其对异形孔加工精度和表面粗糙度的影响 ,探讨了铣削、磨削加工镍基高温合金涡轮盘异形孔的可行性。研究结果表明 ,通过优化加工参数 ,涡轮盘异形孔钻削 铣削工艺可有效替代常用的电火花加工工艺。 相似文献
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Xiaobin Cui Jun Zhao 《The International Journal of Advanced Manufacturing Technology》2014,71(9-12):1811-1824
In the present study, high-speed face milling of AISI H13 hardened steel was conducted to investigate the cutting performance of coated carbide tools. The characteristics of chip morphology, tool life, tool wear mechanisms, and surface roughness were analyzed and compared for different cutting conditions. It was found that as the cutting speed increased, the chip morphology evolved in different ways under different milling conditions (up, down, and symmetric milling). Individual saw-tooth segments and sphere-like chip formed at the cutting speed of 2,500 m/min. Owing to the relatively low mechanical load, longest tool life can be obtained in up milling when the cutting speed was no more than 1,000 m/min. As the cutting speed increased over 1,500 m/min, highest tool life existed in symmetric milling. When the cutting speed was 500 m/min, owing to the higher mechanical load, the flaked region on the tool rake face in symmetric milling was much larger than that in up and down milling. There was no obvious wear on the tool rake face at the cutting speed of 2,500 m/min due to the short tool-chip contact length. In symmetric milling, the delamination of tool material, which did not occur in up and down milling, was caused by the relatively large cutting force. Abrasion had great effect on the tool flank wear in symmetric milling. With the increment of cutting speed, surface roughness decreased first and then increased rapidly. Lowest surface roughness can be obtained at the cutting speed of about 1,500 m/min. 相似文献