中文摘要：

SPH方法是一种拉格朗日型无网格粒子方法.本文针对传统SPH方法核近似精度较差的特点,介绍二阶核近似SPH方法（K2_SPH）.通过与传统SPH方法和移动最小二乘法的对比分析,得到K2_SPH方法核近似的精度特点,然后应用K2_SPH方法对无网格计算方法经典算例之一的平板流体问题进行研究.结果表明,随着核近似精度的改进,K2_SPH方法的计算结果较传统SPH方法在计算精度和稳定性上都有大幅提高.

英文摘要：

SPH is a Lagrangian mesh-free particle method.According to the low accuracy characteristics of kernel approximation for traditional SPH,a second order kernel approximation SPH（K2_SPH） was introduced.After the comparison of traditional SPH and the moving least square method,the accuracy characteristics of K2_SPH were obtained.Then K2_SPH was applied to simulate the flat plate flow,which is one of typical benchmarks for the meshless particle method.With the improvement of kernel approximation,the results of K2_SPH show higher accuracy and more stability compared with traditional SPH.