长脉宽爆炸波与圆柱壳作用的波系演化与载荷分布特征OA北大核心CSTPCD

The wave propagation and pressure distribution during the interaction between long duration blast waves and structures are important foundations for the large scale explosion protection design and safety assessment.In order to understand the interaction mechanism between long duration blast waves and cylindrical shells,as well as the distribution law of the surface load on the cylindrical shells under their action,the overpressure histories on the cylindrical structure surface were obtained through the 150 ms long duration blast wave shock tube experiment,and the shock wave evolution and the pressure load distribution were investigated numerically using the large eddy simulation and hybrid WENO-TCD(weighted essentially non-oscillatory-tuned centered difference)method.The results show that the overpressure load of the calculation results is in good agreement with the experimental results,and the overpressure load on the cylindrical shell appears a clear angle and height correlation.The pressure on the back shell is higher than that on the side surface or even comparable to the blast on the facing surface,which exhibit different pressure attenuation modes from the traditional short duration blast wave propagation.The sudden expansion on the side surface is the main reason for the initial oscillation of pressure,and has a lower pressure than that at the windward and leeward sides.On the other hand,a series of diffracted shock waves collides and reflects on the symmetry plane of the shell leeward,as well as the stationary and superimposed effects of the series of decelerating shock waves near the 135°phase,which are the main mechanisms that cause the overall increase of the pressure load on the cylindrical shell.In addition,the formation and evolution of wake vortex structures on the leeward side due to the boundary effects is a key factor leading to differences in the load distribution along the height direction.The above analysis methods and related results lay the foundation for the subsequent study of load distribution models for typical structural components under long duration blast waves.