介绍了基于上面核爆炸偏转小行星的基本原理,建立了计算模型,采用有限元方法以及能够描述气化反冲的PUFF物态方程进行了数值模拟。假定小行星是由花岗岩构成的密实球体(密度为2.63g/cm3,直径取300m,质量为3.7×1010 kg),核爆炸装的TNT当量取100万吨,核爆炸X射线能谱为1.5keV黑体谱,爆炸距离小行星表面1000m,可在小行星表面产生约1.4×1010N·s的气化反冲冲量,该冲量可以使小行星产生0.38m/s的附加速度。若小行星速度取为20km/s,且冲量方向与小行星速度垂直,可以产生1.1×10-3度的最大偏转角。结果表明,利用核爆炸是完全可以对小行星进行有效偏转的。此外,由于影响因素较多,本文对后续研究进行了展望。
In this paper we introduce the basic theory of asteroid deflection via standoff nuclear explosion.The simulation model is established involving FEM method and PUFF equation-of-state.In the simulation scenario we display,the diameter of the dense spherical asteroid is 300m and it consists entirely of granite(density is 2.63g/cm3)with a mass of 3.7×1010 kg.The standoff nuclear TNT equivalent is 1 million tons and the X-ray spectrum is 1.5keV.The burst height is set as 1000m and this nuke explosion could produce a 1.4×1010 N·s blow-off impulse,which may generate an 0.38m/s extra speed for the asteroid.Assuming the axial speed of asteroid is 20km/s,this vertical extra speed could lead to a 1.1×10-3degree deflection angle.The results show that the asteroid can be deflected effectively by using a standoff nuclear explosion.In addition,due to many influencing factors,we make an outlook for the follow-up research.
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