The Calculation Of Thermal Parameters And The Characterization Of Energy Release In Themobaric Explosions

Objective to formulation design of of Thermobaric Explosive (TME) and reasonable distribution of energy release, this dissertation has made a systematic research of thermal parameters and energy release of TME by theoretical analysis, experiment study and numerical simulation. The main research contents and results are as follows:1.Research on representation and calculation of TME thermal parameters. Not only the energy release characteristics of TME and its action principle have been explained, also the three stages reaction mechanism and thermal parameters have been proposed. In order to improve the calculation accuracy of the explosion heat and detonation heat of composite explosives with high aluminized content, a suit of new empirical method was established. The calculation results are in good accord with experimental data. Compared with commonly used methods, the calculation accuracy has been significantly improved. Two computational programs were compiled for calculating the parameters of afterburning energy and products, by using an aluminum particle diffusional combustion model and complex chemical equilibrium method respectively. Furthermore, the influence factors of afterburning reaction were computationally studied.2.TME energy calculation software was programed, through which the afterburning performance influence factors of main components has been computationally studied, and we have proposed a new formulation design method based on energy. Optimization design on the aluminum content of 20% to 60% RDX-AP-Al three components TME, and the result shows that when the aluminum content is from 20 to 30%, the RDX/(RDX+AP) ratio from 0.55 to 0.70 is more appropriate, when the aluminum content is from 40 to 50%, the RDX/(RDX+AP) ratio from 0.65 to 0.8 is more suitable when aluminum content reaches 60%, RDX/(AP+RDX) ratio is from 0.75 to 0.9.Six kinds of TBE series optimization formulation were finally made.3.The aluminum content and of aluminum particle diameter impact on the energy release of TBE series TME formulation were studied by the method of static detonation in opened space, and the laws of energy release were characterized by shock wave overpressure and impulse and the maximum temperature and maximum diameter of explosion fireball. The different aluminum content experimental results indicate that the charge with 40% aluminum content achieves the best performance with overpressure and impulse. Furthermore, the higher overpressure performance of explosion field was reflected by low aluminum content formulation, the higher afterburning performance, and the high content formulation was embody on shock wave impulse and explosion fireball parameters; The different diameters of aluminum particle experimental result shows that the shock wave were significantly strengthened with small particles of aluminum powder in near field, and the better performance by moderate burning rate of large particles in far field, and the gradation formulation which mixed with different particle size aluminum powder has achieved the best performance. The energy software calculation results show that the charge with 40% aluminum content achieves the maximum afterburning energy. The Al reaction degree has sharply declined when the aluminum content exceeds 40%, and huge potential energy would not be released.4. The aluminum content effect on the energy release of TBE series charges were determined by using the blast chamber in confined space, and the laws of overpressure and impulse of shock wave were analyzed. The result shows that the charge with 30% aluminum content achieves the best performance. The numerical simulation of TBE-30 shock wave propagation has been carried out by using the AUTODYN hydro-codes, and the JWL-Miller EOS parameter of TBE-30 was calculated by software. The numerical simulation result shows that the shockwave curve is in good accord with the experimental result, and the maximum error of overpressure and impulse is less than 10% or 5% respectively.5. The energy release of TBE series charges were measured in underwater explosion, and the laws of aluminum content, particle size, the atmosphere type and pressure of the atmosphere influence on the shock wave energy, bubbles energy and total energy were studied through bi-layer inflatable reaction tank. The result indicates that, with the aluminum content increased, shock wave energy, bubbles energy and total energy were increased at first and then decreased. When Al content reaches 40%, shock wave energy of charge can be maximal (1.702 times TNT equivalent). When Al content was around 50%, bubbles energy and total energy of charge were maximal,(1.702 times TNT equivalent). With the increased oxygen content in tank increased, shock wave energy, bubbles energy and total energy were increased as well. And, the aluminum particle size have little effect on the underwater energy release.