PBX药柱温升过程中的性能变化研究

为全面了解温升过程中PBX药柱温度、应力和尺寸变化情况,利用瞬态-应力耦合有限元法对药柱温升过程进行模拟。结果显示:药柱温升过程中,热量逐渐向内部传递,初始升温阶段应力增大很快,最大达到2.37MPa,随着内外温差的减小而逐渐减小;药柱尺寸增大,密度减小约0.008g.cm-3。通过模拟可以初步确定药柱温升过程内部应力变化规律,预估尺寸和密度变化量,优化设计了一种炸药加热工艺,即将加热分四段进行,尽量降低升温速率,保证至少1800s的恒温时间。

Properties for PBX cylinder during temperature rising

Finite element numerical simulation based on transient thermal stress coupled analyses was conducted to understand the temperature, stress and dimensions for PBX cylinder during temperature rising. Results show that with temperature rising, heat transfers from surface to inner; stress augments rapidly at beginning, even arrives to 2.37 MPa, then reduces with temperature difference decreasing, the size of PBX cylinder is grown and its density is decreased by about 0.008 g·cm^-3. Numerical simulation can preliminary determine the regularity of stress distribution. And heating process has been optimized to try to decrease the rate of temperature rising and ensure at least 1800 s temperature constant time.