梯恩梯/黑索今(35/65)炸药的反应速率函数

REACTION RATES OF TNT/RDX(35/65)explosive

本文采用Lagrange分析方法和冲击引爆实验数据研究了TNT/RDX(35/65)炸药的反应速率函数。在冲击压力4.69GPa(持续时间约1μs)的作用下,采用F4/203A型锰铜压力计测量了样品内六个不同Lagrange位置上的压力历史。以此作为输入量,采用Lagrange分析方法计算了反应流场中的速度、密度和比内能历史。根据这些结果,再使用HOM、JWL和γ律爆轰产物状态方程计算了反应进程和反应速率。在此基础上采用最小二乘法拟合了Forest Fire和Cochran点火-成长速率函数中的待定系数。考察了不同产物状态方程对这些系数的影响。用HOM和JWL方程得到的速率函数,基本一致,但用γ律方程得到的速率比前两者低,这是由于在反应区中有明显熵增的缘故。在较高压力下,本文给出的Forest Fire速率同Mader依据POP关系和反应Hugoniot算出的Comp.B炸药的结果有一定差别。使用得到的这两种速率函数进行了一维数值模拟计算,计算结果同实验基本一致。

The reaction rates of TNT/RDX (35/65) explosive have been studied with the Lagrange analysis and shock initiation data. The explosive samples with diameter of 60mm were initiated under a shock of pressure 4.69GPa and lasting time 1 μs by means of a flyer driven by an explosive plane wave lens and an attenuator consisting of PMMA and steel slabs. The pressure histories at six Lagrange positions (h=0.0mm.3.00mm, 4. 05 mm, 5.05 mm, 6. 30 mm, 8.05 mm) were measured by using the F4/203A type manganin perssure gauges. These histories have been smoothed by the least square cubic B-spline method. With these input data the Lagrange analysis were performed and the histories of velocity, density and specific internal energy in the reactive flow have been obtained. Under the assumptions of pressure and temperature equilibrium, we denote the specific .internal energy and volume of the reacting mix -ture as the weighted averages of those variables of unreacted explosive and detonation products, where the weight is the reaction degree to be calculated. The reaction degree and rates have been yielded by using the HOM, JWL as well as the γ-Law EOS (Equation of state ) of detonation products.Based on the tabular data for the pressure, density, specific internal energy, temperature, reaction degree and rates, some, important empirical reaction rates could be determined. For examples, the coefficients in the Forest Fire rate and the ignition-growth rate suggested by S.G.Cochran and J.Chan were determined by the least square method. The influences of different EOS of detonation products on the rates have been investigated .The rates from HOM and JWL EOS are consistent with each other, however, the rate from γ-Law EOS is less than the above two in a wide range of pressure because the entropy increases considerably in the reaction zone. The Forest Fire rate shows some differences from that of comp. B explosive given by C.L.Mader's approximate calculation with the POP relation and the reaction Hugoniot. The result of the one-dimensional numerical simulation with the above rates are consistent well with the experimental data of shock initiation.