强爆炸早期火球光辐射能谱的数值计算

基于强爆炸火球光辐射的多群辐射流体力学方法, 采用算子分裂方法将方程组分裂为对流项和刚性源项, 其中源项部分根据方程形式, 进一步分裂为各群内的单独求解。数值计算表明:该方法克服了直接求解过程中辐射与流体耦合所带来的强不稳定性, 时间步长大幅提高, 给出的火球光辐射能谱特征与已有规律一致。可为定量分析光辐射能谱特征提供有效手段。

Numerical calculation of early fireball radiation spectrum in strong explosion

On the basis of multi-group radiation hydrodynamics method of fireball radiation in strong explosion, operator splitting method is used to split the equations into convection items and source items, which are split into radiation groups due to the equation formation and solved individually.Numerical calculations show that the method used here overcomes strong instability when solving the equations directly because of the coupling items between radiation and fluid.In the meantime, the time step in the calculation is increased obviously.Fireball radiation spectrum is obtained in fine accordance with the result in the literature.