多孔聚氨酯基复合削爆屏障的防护性能

In view of the hot problem of reducing the harm of explosive terrorist attacks in public security field, the research on explosion-proof structures is urgent. Polyurethane foam has the advantages of being lightweight, has excellent mechanical properties, and can avoid secondary debris damage. It has a good application prospect in the new explosive disposal equipment. Based on the research background of explosion hazard reduction, the mechanism and effectiveness of shock wave weakening of polyurethane foam and polyurethane-based composite barriers need to be investigated. The microstructure and mechanical properties of porous polyurethane were tested firstly. It was to obtain the basic parameters and contribute to construct the simulation model of the samples with different densities (100-300 kg/m³). A directional flow field device was set up to impact the polyurethane plate and the feasibility of the corresponding numerical model was analyzed to study its protective performance against the plane shock wave. On this basis, the weakening effect of the polyurethane-water annular composite barrier under internal explosive loading was analyzed numerically by using the verified numerical model. The design premise was that the total volume of barriers was equal, and the shockwave weakening performances of PU/water, pure water and water/PU barriers were compared. The influence of polyurethane density on shock wave weakening performance was analyzed. The results show that the existence of a barrier forces the shock wave to reflect, diffract, transmit and interact with each other. Compared with a pure water barrier, the PU/water barrier can effectively reduce shock wave peak (up to 13.3%) when the total mass decreases by 32%. This is mainly because of the lower impedance of the inner polyurethane foam, which can reduce the strength of the shock wave reflected back from the barrier wall. Under current simulation conditions, it is more effective for the protection of corresponding barrier when the density of PU is 200 kg/m³ in the PU/water barrier.