可拓学在采矿工程中的应用及展望

可拓学采用形式化的工具,从定性和定量的共同角度研究和解决现实中的矛盾不相容问题,目前已形成了自己的理论框架,并通过与各工程应用领域的相结合,形成了可拓学工程应用,取得了一定的成果。本文简单介绍了可拓学的发展历史和可拓学基本原理,对可拓学在采矿工程领域中的应用进行了分类,阐述其在解决采矿工程问题的一般方法,指出了应用中存在的一些问题,最后展望了可拓学在采矿工程中的应用前景。     

立方体预制破片战斗部破片初速计算模型

为了建立立方体破片的初速计算模型,运用AUTODYN软件分析已有试验的爆炸驱动过程,将其分为爆炸产物不泄露和泄露两阶段,基于系列假设、冲量定理和修正的爆炸产物压强公式建立了全过程的立方体破片速度计算模型。该模型给出的破片初速值与试验结果吻合较好,并反映出立方体预制破片的初速还与周向破片数量及驱动过程中破片的最大周向形变量有关。     

小口径榴弹自然破片形成过程的数值模拟

采用AUTODYN软件中基于Mott分布生成自然破片的Stochastic材料破坏模型,对30mm小口径榴弹壳体膨胀和自然破碎过程进行了数值模拟,获得了破片初速、飞散角沿轴向曲线分布及破片质量分布,仿真结果与破碎性试验回收破片的统计结果吻合较好。     

Analysis Model on Penetration Depth of Concrete by Eroding Long-Rod Projectiles

Mass loss should be considered while calculating the penetration depth of concrete by eroding long-rod projectiles of high velocity.The penetration process is divided into two phases:eroding phase and rigid phase.During eroding phase,a model to predict the penetration depth is established on the assumption that there is a chipping region in the bottom of crater.During rigid phase,Forrestal formula is adopted to calculate the penetration depth.Using this model,the depth of concrete penetration by a tungsten alloy long-rod projectile is calculated.When the critical eroding velocity is between 950 m/s and 1 000 m/s,the result is in good agreement with the experimental data.     

Study on fragmentation of PELE against thin targets

The fragments mass and size from penetrator with enhanced lateral effect (PELE) perforating thin rolled homogenous armor (RHA) target was characterized through theoretical and numerical methods. An analytical model based on energy-limited spall (ELS) was proposed to predict fragments mass distribution of PELE with different cores and impact velocities. For different cores the expansion can be represented by a scaling factor l in the analytical calculation. The explicit finite-element (FE)-analysis of PELE f...     

EFP的气动及终点弹道优化设计新方案

本文针对常规EFP的飞行阻力大、稳定性差的缺点,以提高其侵深为目标,在综合研究轴对称裙式EFP弹形参数对气动性能及终点弹道影响规律的基础上,提出一种新的具有工程实现可能性的EFP气动优化方案:对于前体,根据杆式头部破甲弹的气动原理,通过增加一尖锥,改善其气动特性;对后体,仍采用简便的裙式,优化裙体参数.经初步分析,综合优化的EFP侵彻性能有显著提高,为其优化设计提供了一条新思路.其工程实现有待进一步研究.     

Numerical study on the shock responses of submunition drop on various mediums

The shock responses of submunition drop on various ground-mediums are modeled and investigated by numerical simulation in this paper. Submunition impacts on concrete surface, gravel ground or sand with various drop velocities, different drop angles and attack angles are calculated in a finite element program. The loads and dynamic responses of submunition are analyzed, curves of various drop velocities, drop angles and attack angles related to peak overload are calculated and law of interaction time on different ground mediums is obtained.     

光面爆破技术在某铜矿回采出矿中的应用

光面爆破技术主要应用在巷道掘进中,且在倾斜矿体难以靠自重出矿的回采过程中其应用效果也很显著。某铜矿结合矿体赋存条件、矿岩界限和出矿方式等因素,将光面爆破技术运用于采场回采,本文对影响出矿效率的因素作了分析。现场应用效果表明:基于光面爆破技术的爆力运搬方式提高了采场综合生产能力,加快了出矿进程,提高了出矿效率,减少了辅助工作量,并降低了倾斜矿体的矿石损失率和贫化率,应用效果显著。     

钨铜射流成形的细观数值模拟分析

为研究钨铜复合材料聚能射流成形的细观机理及材料细观结构对射流成形的影响,基于随机投放原理编制了钨铜复合材料细观离散化模型生成程序,建立了不同两相配比及钨颗粒尺寸的钨铜药型罩细观离散化模型。应用动力学仿真AUTODYN-2D软件中的欧拉算法,对钨铜细观模型及其等效均质药型罩开展了聚能射流成形的细观尺度有限元数值模拟分析。研究结果表明,钨铜材料在爆炸载荷驱动下铜相与钨相速度有显著差异,钨颗粒含量沿射流尾部至头部分布不均匀,呈现依次递减的趋势。在一定钨颗粒尺寸下,射流中钨含量相对变化量随着原始药型罩中钨含量降低而增大,钨体积含量30%的钨铜材料形成射流中平均钨含量降低65%,其中头部钨含量下降达90%;在给定罩材两相配比时,射流中钨含量随着钨颗粒尺寸的增大而降低,高钨含量的钨铜射流成分分布不均匀性对颗粒尺寸的变化更加敏感。     

Simplified Approach to Velocities of Axial Forward Projection Fragments from the End of a Warhead

A warhead with axial forward projection fragments is one of the most important forms of aimable warheads. For such warheads the axial forward projection fragments are placed at the end of the explosive charge and form a fragment beam with high fragment density and high speed by the blast, which will obviously increase the damage to the targets. Experimental data showed that the velocities of the forward projection fragments on the convex end of a warhead which was initiated at the opposite end do not match that predicted by the Gurney equation for cylindrical warheads. A new approach for addressing the velocities of fragments of this kind of warhead is proposed. Two limiting conditions are defined, i.e. for fragment on the circumference of a cylindrical charge and fragments on the end of cylindrical charge, respectively.