Confined Space Blast Wave Pressure Test And The Inner Wall Of The Pressure Distribution Studies

In this paper, experimental and numerical study were conducted to obtain the overpressure distribution on the inner wall after an explosion of a high explosive charge in the center of confined space, the main contents and conclusions include:1) A micro pressure test system was designed, the main functional modules of the circuit were analyzed and the mathematical model of the test system was obtained. Several field tests indicated that the pressure tester can be a good acquisition to the blast wave pressure signal, and the reliability, ease of operation have been fully reflected.2) Experimental study was conducted on charge explosion in a cylindrical explosion container. Overpressure time history of the same point with different charge weights and different points with the same charge weight were analyzed and compared, impulse corresponding to the first peak of each measuring point were also calculated. Results indicate that superposition and multiple reflections of shock wave front are the most significant features that differ from the free-field blast. The first peak reflected overpressure on each measuring points increases as the charge weight increases, Impulse corresponds to the first peak of measuring point is relate to the distance from the explosive charge and its location of the structure.3) Charge explosion in cylindrical explosion vessel is simulated. Images displayed propagation, reflection and superposition process of the blast wave at real-time. Numerical and experimental results agree well with each other. Points of the inner wall with the maximum peak overpressure after an explosion of a high explosive charge at the center of chamber were obtained by selecting feature points. The impact on overpressure of measuring points due to the variation of charge shape and a small deviation of charge position was studied and the feasibility of treating inner wall as rigid was analyzed.4) Charge explosion in reinforced concrete box structure is simulated. Points of the inner wall with the maximum peak overpressure after an explosion of a high explosive charge at the center of rectangular and cubic structure were obtained by selecting feature points at the same way. The clustering effect will get stronger at Areas of intersection of two planes and intersection of three planes, and make positive time and impulse longer and larger.5) The explosion similarity in confined space was analyzed. Results indicated that, similar to an explosion in free field, when two charges exploded at the center of a confined structure and a scaled one each, the peak overpressures on corresponding measuring points have the same value if the scaled distance (?) is the same to each other,and the positive time meets the equation (?)...