双锥药型罩射流成型的理论建模与分析

Theoretical Modeling and Analysis on Jet Formation of Biconical Liner

为了提高射流在侵彻全过程的破甲效率,设计了一种顶部小锥角、口部大锥角的双锥形药型罩;基于PER理论,利用Gurney公式和Chanteret公式联合求解药型罩压垮速度,建立了封闭的射流成型理论模型;利用理论模型和数值模拟计算并分析了40°和80°锥角单锥罩与上、下锥角分别为40°、80°双锥罩射流的成型形状和成型参数,通过数值模拟研究了双锥罩结构参数(双锥罩上锥角、上锥高占罩高的比例、罩高和壁厚)对射流头部速度和拐点速度的影响,并通过X光试验获得了双锥罩射流的成型效果。结果表明,在头部颗粒堆积点之后,单锥罩与双锥罩射流分别呈线性与双线性分布,双锥罩射流兼顾了上锥高头部速度、下锥射流直径较大的优点;当上锥角从18°增大到34°时,头部速度降低了10.4%,而拐点速度降低了25%;当双锥罩上锥高占罩高比例从30%增大到70%,头部速度增加了11.8%,拐点速度降低了19.9%;当罩高从125 mm增大到155 mm,头部速度增加了4.2%,拐点速度降低了11.4%;当壁厚从1.8 mm增大到3.4 mm,头部速度降低了8.4%,而拐点速度降低了18.4%。通过理论分析、数值模拟和X光试验结果的对比,得到三者的射流成型吻合较好。

In order to improve the efficiency of the jet during the whole penetration process of the armor,a biconical liner with a small conical angle at the top and a large conical angle at the bottom was designed.Based on PER theory,using Gurney formula and Chanteret formula to solve the collapsing velocity of liner,a closed theoretical model of jet formation was established.Based on the theoretical model and numerical simulation,the jet shape and formation parameters corresponding to the single conical liner with 40°and 80°and the biconical liner with the top angle 40°and the bottom angle 80°were calculated and analyzed,respectively.The numerical simulation was carried out to study the structural parameters of a biconical liner including the top conical angle,height ratio of top cone,the height and liner thickness of the biconical liner,which influence the tip velocity and inflection velocity.Also the jet formation effect of the biconical liner are obtained by means of the X-ray test.The results show that the jet of single conicale liner and biconical liner are linear and bilinear after the accumulation point of particles in the head.The biconical liner jet integrates the advantages of high head velocity of upper cone and large jet diameter of lower cone.When the upper conical angle increases from 18°to 34°,the head velocity decreases by 10.4%,and the inflection point velocity decreases by 25%.When the ratio of the upper conical height to the liner height increases from 30%to 70%,the head velocity increases by 11.8%,and the inflection point velocity decreases by 19.9%.When the liner height increases from 125 mm to 155 mm,the head velocity increases by 4.2%,and the inflection point velocity decreases by 11.4%.When the liner thickness increases from 1.8 mm to 3.4 mm,the head velocity decreases by 8.4%,and the inflection velocity decreases by 18.4%.Through the comparison among theoretical analysis,numerical simulation and X-ray test results,the results are in good agreement.