Numerical Simulation of Bolide Entry with Ground Footprint Prediction
Numerical Simulation of Bolide Entry with Ground Footprint Prediction
复制标题
具有地面足迹预测的火流星进入数值模拟
DOI：
--
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
M. Berger
中科院分区：
文献类型：
--
作者：
M. Aftosmis;M. Nemec;D. Mathias;M. Berger
当流星在大气层中减速时，它们以惊人的速度将质量、动量和能量存款到周围的空气中。这种火流星进入地球时产生的创伤会产生强烈的冲击波，即使没有发生地面撞击，冲击波也能传播数百公里，对地球造成重大破坏。我们提出了一种新的模拟技术，空爆预测使用完全保守的，笛卡尔网格，有限体积求解器，并调查这种方法的能力，以模拟远场传播超过数百公里。这项工作建立了质量、动量和能量在大气中沉积的数学模型，并通过典型问题以及表面超压和爆炸到达时间与已知火流星文献中的实际结果的比较进行了验证和确认。讨论还检查了各种近似的影响，可以大大减少这些模拟的计算费用的物理火流星进入。我们提出了参数的研究，以量化的影响，进入角，爆炸高度和其他参数的地面足迹的空中爆炸，这些值是相关的预测分析和手册的方法。
As they decelerate through the atmosphere, meteors deposit mass, momentum and energy into the surrounding air at tremendous rates. Trauma from the entry of such bolides produces strong blast waves that can propagate hundreds of kilometers and cause substantial terrestrial damage even when no ground impact occurs. We present a new simulation technique for airburst blast prediction using a fully-conservative, Cartesian mesh, finite-volume solver and investigate the ability of this method to model far- field propagation over hundreds of kilometers. The work develops mathematical models for the deposition of mass, momentum and energy into the atmosphere and presents verification and validation through canonical problems and the comparison of surface overpressures, and blast arrival times with actual results in the literature for known bolides. The discussion also examines the effects of various approximations to the physics of bolide entry that can substantially decrease the computational expense of these simulations. We present parametric studies to quantify the influence of entry-angle, burst-height and other parameters on the ground footprint of the airburst, and these values are related to predictions from analytic and handbook-methods.