通过求解质点运动方程的数值进行7.62毫米/0.308英寸步枪子弹的弹道模拟
- 作者: Gangopadhyay S.1, Rohatgi R.1
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隶属关系:
- National Institute of Criminology and Forensic Science
- 期: 卷 8, 编号 2 (2022)
- 页面: 23-36
- 栏目: ORIGINAL STUDY ARTICLES
- URL: https://journals.rcsi.science/2411-8729/article/view/122463
- DOI: https://doi.org/10.17816/fm730
- ID: 122463
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背景:在弹道学中,了解弹道动力学对于精确估计各种飞行变量的数值非常重要。本文研究外弹道的基本原理,通过求解质点运动方程的数值,深入研究7颗0.308英寸口径子弹的自由飞行弹道的弹道特性。通过用Python编程语言编写脚本并使用Matplotlib库绘制模拟弹道来进行数值求解。
目的。该研究的三个目的是观察CD随飞行马赫数(Ma)的变化,并计算每颗子弹的平均CD。此外,求解给定子弹的三自由度(3-DoF)质点弹道运动方程(同时观察射程风作为变量对弹道行为的影响)。最后,通过分析侧风的影响来求解平射近似。
材料和方法:通过数值求解运动方程模拟七颗不同的7.62毫米/0.308英寸步枪子弹(指定为B0-B6)的自由飞行弹道。 参照G7标准弹,计算B0-B6的平均阻力系数(CD)随飞行马赫数的变化。 在分别受以及不受射程风影响的情况下,研究质点弹道模型及其平射近似。用Python编程语言编写的脚本进行方程组求解。
结果。观察发现,子弹重量的增加以及因此导致的截面密度的增加使CD降低。正如预期的那样,可以看出,阻力最大的子弹(B0)射程最短,远地点最低,而阻力越小的子弹飞得越高越远。在枪仰角约30°时观察到弹道交叉,这意味着以45°角射击时无法达到最大射程,这与真空弹道相符。质点模型的平射近似也得以解决,以观察子弹在<5°仰角下发射时的弹道和侧风偏转。
结论。本项目提出了通过求解从步枪发射的子弹的质点模型运动方程的数值,对其弹道进行计算模拟。选择了一组7颗7.62毫米/0.308英寸的步枪子弹为样本,模拟其自由飞行弹道。由于编程语言Python内置的函数库有助于编写高效脚本并减少计算负载,Python能够很好地执行微分方程组的数值解。该解决方法可以在适当修改后,应用于法医弹道学重建子弹弹道,并根据犯罪现场的可用证据得出结论。
作者简介
Soham Gangopadhyay
National Institute of Criminology and Forensic Science
Email: rrohatgi2020@gmail.com
Post Graduate Student, MSc Forensic Science
印度, New DelhiRicha Rohatgi
National Institute of Criminology and Forensic Science
编辑信件的主要联系方式.
Email: rrohatgi2020@gmail.com
ORCID iD: 0000-0001-5514-953X
Scopus 作者 ID: 57189091058
MSc, PhD, Assistant Professor, Forensic Science
印度, New Delhi参考
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