论文部分内容阅读
为了得到更准确的飞机鸟撞分析模型,基于显式有限元分析程序PAM-CRASH建立了LY12-CZ铝合金平板的鸟撞数值模型.采用Johnson-Cook方程表述LY12-CZ材料的本构.LY12-CZ铝合金在4种不同应变率下的应力-应变曲线通过电子万能试验机和分离式霍普金森拉杆(SHTB)拉伸试验获得,对曲线进行拟合得到Johnson-Cook方程中的4个常数.基于光滑粒子流体动力学(SPH)方法建立了鸟体模型,引入Monaghan EOS方程来描述鸟体材料.针对所建立的鸟撞数值计算模型,开展相对应的鸟撞试验,获得测试点的应变,并将数值计算结果和试验结果进行对比.结果表明:计算应变与试验测得的应变吻合较好,验证了鸟体、铝合金本构模型以及鸟体高速冲击计算分析模型的合理性、可靠性.
In order to get a more accurate bird strike analysis model, a bird strike numerical model of LY12-CZ aluminum alloy slab was established based on explicit finite element analysis program PAM-CRASH.The Johnson-Cook equation was used to describe the constitutive of LY12-CZ material.LY12 The stress-strain curves of CZ aluminum alloy at four different strain rates were obtained by tensile testing of electronic universal testing machine and separate Hopkinson pull rod (SHTB). The curves were fitted to obtain four of the Johnson-Cook equations Constant.Based on the method of smooth particle hydrodynamics (SPH), the bird body model was established and the Monaghan EOS equation was introduced to describe the bird body material.According to the established bird impact numerical model, the corresponding bird strike test was carried out to obtain the test points The results show that the calculated strain is in good agreement with the measured strain, which verifies the rationality of the constitutive model of bird body, aluminum alloy and the calculation and analysis model of bird body high speed impact. reliability.