水下爆炸近场峰值压力的数值模拟

为了研究水下爆炸近场内的压力状态,使用SPH (smoothed particle hydrodynamics)方法,采用C-J爆轰模型,对水下爆炸过程进行了数值模拟。通过与峰值压力规律和中场内经验公式的比较,验证了程序的可靠性。对水下爆炸过程进行了波系分析,与不同维数水下爆炸的数值模拟结果进行了对比研究。结果表明:比距离R/a=6是波形变化的一个分界点,在R/a<6的近场范围内,峰值压力的拟合分为两段更合适。另外,对数值结果的ln Pm-ln(R/a)曲线进行了分段幂次拟合,得到了与数值模拟结果非常吻合的拟合曲线。

Numerical simulation of peak pressure in near-field underwater explosion

In this work, to obtain the pressure state of underwater explosion in near-field, we numerically simulated the whole process of underwater explosion using the smoothed particle hydrodynamics and adopting the C-J detonation model, and following the empirical formulas, confirmed the laws of the peak pressure, thereby verifying the effectiveness of the numerical program. We also analyzed the waves' propagation in underwater explosion and compared it with the numerical results of underwater explosion in various dimensions. The results show that the distance ratio R/a=6 is a demarcation point in the waves structure, and in the R/a＜6 near-field range the fitted peak pressure curve should be divided into two sections. Further, we performed segmented fitting of the numerical results with power function, and found the fitted curve in good agreement with the numerical results.