光面爆破椭圆双极线性聚能药柱有效功及不耦合系数模拟研究

基于动力学仿真软件AUTODYN,对椭圆双极线性聚能药柱(EBLSC)进行了数值模拟。采用二维面对称计算方法,花岗岩岩体,空气夹层不耦合装药条件,研究了EBLSC结构及不耦合系数对光面爆破效果的影响,并建立有效体积功模型以评价爆破效果。结果表明,炮孔连线方向和垂直方向上的比冲量相近,偏差10%,故总能量沿周向近似均匀分布,但炮孔连线方向产生明显侵彻裂隙,且粉碎圈厚度和腔体扩张程度要小得多,表明该装药结构能够明显提高炸药能量的利用率和爆破效果;随着不耦合系数增大,炮孔连线方向上的损耗体积功先减小后增大,存在最大有效功。利用曲线拟合,得到最优不耦合系数约3.62,与相关文献的试验结果相近。

Simulation Study on Effective Work and Non-coupling Coefficients of Elliptic Bipolar Linear Shaped Charge for Smooth Blasting

Numerical simulation was done on the elliptic bipolar linear shaped charge (EBLSC) based on dynamics simulation software AUTODYN. First, through two-dimensional planar symmetric method and considering granite characteristics, air sandwich and decouple condition, the effects of EBLSC structure and decouple coefficient for smooth blasting were studied. Then, the effective volume work model was established to evaluate blasting results. The results indicated that the specific impulses on blasthole line connecting direction and in vertical direction were similar with deviation below 10%, so the whole energy of charge uniformly was distributed along the circumferential direction approximately. However, there were obvious penetration cracks in blasthole connecting direction with lower crushing and expanding degree of the rock. It indicated that EBLSC could improve significantly the charge energy efficiency and blasting result. In addition, with the decouple coefficient increasing, the loss or waste volume work in blasthole connection direction first decreased and then increased with the existence of maximum effective power. Through curve fitting, the optimal decouple coefficient of about 3.62 was obtained, which was similar to the result of relevant experiments.