摘要
为了解2,4-二硝基苯甲醚(DNAN)的凝固过程,用布拉格(Bragg)光栅对其凝固过程的中心轴线温度场进行了测试。考虑了液相自然对流的微观现象。用控制容积法计算了DNAN凝固过程的温度场、流场和相界面位置。用临界固相率和补缩距离结合法预测了缩孔编松的生成。结果表明,DNAN在96℃附近出现温度滞后现象,中心部位最明显。前期液相自然对流的最大速度可达10-3量级(m·s-1),其作用为传质和加速凝固进程。无冒口补缩条件下,DNAN凝固过程中相界面呈"V"字型向顶部迁移、收缩,凝固后中心轴线上有连续的缩孔分布,中心处的最大孔隙率为0.38。
o understand the solidification process of 2,4-dinitroanisole（ DN AN）,the temperature field in the central axis in the solidification process w as tested by Bragg gratings. T he microscopic phenomenon of natural convection of liquid phase w as considered. T he temperature field,flow field and phase interface position for the solidification process of DN AN w ere calculated by volume-control method. T he formation of shrinkage holes and shrinkage porosities w ere predicted by considering both critical solid phase fraction and feeding length. R esults show that the temperature hysteresis appears at about 96 ℃ and most obvious in the center. T he maximum velocity of natural convection of the early stage of liquid reaches 10-3magnitude（ m·s^-1）. This natural convection helps to transfer mass and to accelerate the process of solidification. U nder no feeding conditions,the phase interface in the solidification process of DN AN is V-shaped,it shrinks and transfers from bottom to top. After contraction and solidification,the shrinkage holes distribute continuously in the central axis of explosive,and the maximum porosity in the center is 0. 38.
出处
《含能材料》
EI
CAS
CSCD
北大核心
2014年第2期240-244,共5页
Chinese Journal of Energetic Materials
基金
火炸药青年基金(08020401-4)
