烟幕初始云团半径变化规律理论模型及实验研究

Theoretical model and experiment of radius variation of initial smoke cloud

为了评估烟幕的遮蔽效能,需要对烟幕云团初始参数进行计算,即烟幕云团在爆炸能量下形成的最大半径。本文中基于一种简单烟幕发生装置,把云团的膨胀过程分为2个阶段,分别为等熵膨胀阶段和自由膨胀阶段,建立了烟幕云团膨胀的理论模型,对模型进行分析建立了烟幕云团膨胀过程微分方程组。采用四阶龙格-库塔方法求解得到烟幕云团的半径变化规律。通过实验结果分析可知,该理论模型能够描述给定装置烟幕云团膨胀的基本规律。通过缩比效应,可将其用于爆炸发烟装置初始云团参数的计算。

The radius of the initial smoke cloud is an essential parameter frequently used when evalua- ting the smoke shelter efficiency. In this paper, the expansion process and the initial parameters of the smoke cloud were analyzed using theoretical assumptions based on a smoke generating device. The expansion process of smoke clouds were respectively divided into the isentropic expansion stage and the free expansion stage, and differential equations of the smoke cloud expansion were then estab- lished through analyzing the expansion process. After that the differential equations were solved using the Runge-Kutta method, and the radius variation with time of the initial smoke cloud was presented. The experiment results prove that this method can be adopted to describe the basic law rules in the ex- pansion of the smoke cloud and to calculate the initial parameters of the smoke generator.