大空间柱壳结构爆炸动力响应的Ritz-POD数值模拟

应用ANSYS/LS-DYNA建立大空间柱壳结构在内爆炸荷载作用下的数值模拟实验,在验证模型及参数选取的正确性及可靠性的基础上,建立了大空间柱壳结构在内爆炸作用下进行动力响应计算的合适模型。将Ritz振型叠加法与POD法结合,解决了冲击波荷载的时空差异性和结构表面压力场分布问题,大大减少了大空间结构爆炸动力响应分析的计算量。对大空间柱面网壳结构在内爆炸冲击荷载作用下的动力响应进行了数值模拟计算与分析,研究了矢跨比和爆炸点位置等因素对结构动力响应的影响。结果表明,计算模型适合于大空间柱壳结构的爆炸动力响应分析,矢跨比大的结构防（抗）爆炸冲击波的能力较强。偏心爆炸比中心爆炸对大空间结构构件的损害大,对结构的边跨构件最为不利,设计中应更注重支座附近和边跨结构的防爆能力。

Numerical Simulation for Dynamic Response of Large-Space Cylindrical Reticulated Shell under Internal Explosion by Ritz-POD Method

A numerical simulation test of the internal explosive loading on large-space structure was carried out by employing algorithm ANSYS/LS-DYNA.An appropriate model was established for calculating the dynamic responses of the large-space cylindrical reticulated shell under inner-blast loading based on the proof of correctness and reliability of the model and parameters selection.Combining the Ritz vibration mode superposition method with the Proper Orthogonal Decomposition（POD） method,the problems of spatiotemporal asynchrony of shock waveforms and pressure distributions on large-space structure surface were solved and the calculation for dynamic response of large-space structure was reduced and simplified.Furthermore,the numerical simulation of dynamic responses was carried out.And the influence of the ratio of rise to span and the explosive position on the dynamic responses of the structure was studied.It was found that the calculation model was suitable for the dynamic response analysis of the large-space cylindrical reticulated shell under internal explosion and the cylindrical reticulated shells with bigger ratios of rise to span were stronger in the capacity of anti-explosion.In general,the damages to the large-space structure caused by eccentric blast shock waves were more serious than that caused by central explosion.And it was the most disadvantageous to the edge components of the structure.The more attention should be paid to the anti-explosion capacity of the support areas and the edge components while designing the shells.