激光点火过程的一维有限差分模型比较

Comparison of One-dimensional Finite Difference Model about the Process of Laser Ignition

建立 4种关于激光点火过程的一维有限差分模型 ,并通过计算对 4种模型的点火延迟时间和药剂表面温度变化曲线进行比较。结果表明 ,这两种因素对点火延迟时间和临界点火阈值的影响不可忽略 ,相比之下 ,化学反应热的影响更大 ,而且随着入射光能量水平的升高两因素对点火延迟时间的影响减小。考虑化学反应热 ,在入射光能量水平较低时 ,药剂表面温度的变化曲线出现双峰现象。

Four one-dimensional finite difference models about the process of laser ignition are developed. Based on the calculations, function time and variation curve of surface temperature of four models is compared. Results show that effect of the two factors on function time and ignition threshold cannot be overlooked, the effect of chemical reaction heat is greater than that of the other factor, and the effect of them on function time reduces along with laser energy rising. If with effect of chemical reaction heat, variation curve of surface temperature of powder appears double peaks while laser energy is lower. The higher laser energy is, the shorter function time is.