电热化学炮内弹道过程无网格法数值模拟

【作者】 朱艳明；

【导师】 李海元；

【作者基本信息】 南京理工大学 ， 热能工程， 2012， 硕士

【摘要】 电热化学炮(ETCG)内弹道过程异常复杂,涉及两相流动力学、传热学、燃烧学、化学动力学、湍流力学、爆轰学等诸多学科,其中还存在多种物理强间断问题,如爆轰波、激波火焰波以及传火孔高速射流等,又由于装药结构和初始装填条件的原因造成药筒间的间隙及弹后自由空间等不连续问题从而形成空间上强间断面。这些物理间断和空间间断给传统的基于网格的数值模拟方法的应用带来了很大的困难。而无网格法最大的优点在于它不需要在问题域中划分网格,这就摆脱了不连续性对问题的束缚(如网格的重构等),保证了求解精度。光滑粒子流体动力学(SPH)数值模拟方法是一种无网格粒子法,它在流体力学和固体力学领域都有广泛的应用,比如在弹性流、磁流体力学、多相流动和金属成型模拟等方面。SPH方法的另外一个重要应用是模拟高能炸药燃烧爆炸现象,是瞬态物理领域新的重要的一种数值模拟方法。本文用SPH方法对固体化学工质电热化学炮的内弹道过程进行数值模拟,这是一个二维轴对称气-固两相流瞬态物理过程。在结合流体力学基本方程组与电热化学炮内弹道基本假设的基础上,用Fortran语言编写了内弹道过程SPH计算程序,对内弹道的一些重要参数,温度、压力和空隙率等随时间、空间的变化进行了模拟分析。计算结果表明,用SPH法编写的内弹道计算程序可行,其结果与实验数据基本吻合。更多还原

【Abstract】 Interior ballistic process of Electrothermal Chemical Guns(ETCG) is extremely complex, which involves two-phase flow dynamics, heat transfer, combustion, chemical kinetics, turbulence mechanics, detonation and many other subjects.There are a variety of physical intensity intermittent problems, such as the detonation wave, shock wave and flame pass the fire-hole high-speed jet, etc. and the gap between the cartridges and discontinuity of playing after the free space which form a strong discontinuity in space is caused by the charging structure and the initial loading condition.Great difficulties is brougth by continuous and intermittent physical space for the traditional method of numerical simulation application based on grid. The biggest advantages of the non-grid method of are that they don’t need mesh in the problem domain,which is free from the shackles of the discontinuity of the problem (such as the reconstruction of the grid, etc.),and ensure the solution accuracy.Smooth particle hydrodynamics (SPH) simulation method is a meshless particle method, which has a wide range of applications in the field of fluid mechanics and solid mechanics,such as the elastic flow, magnetic hydrodynamics, multiphase flow and metal forming simulation and so on.Another important application of The SPH method is simulationing high explosive combustion and explosion phenomena,which is an important new numerical simulation method in transient physics.This dissertation simulates the interior ballistic process of Electrothermal Chemical Guns with medium of solid-state chemistry by means of the SPH method, fluid within the process simulation,which is a transient physical processes of two-dimensional axisymmetric an gas-solid two-phase.The basic equations of fluid mechanics in combination with Electrothermal Chemical Guns interior ballistic assumption, based on written in Fortran computer program within the SPH interior ballistic process, interior ballistics of some important parameters, temperature, pressure, and porosity and other space-time changes in the simulation analysis. The results show that the computer program of trajectory written by the SPH method is feasible,and the results basically accord with experimental data.更多还原