删除或更新信息,请邮件至freekaoyan#163.com(#换成@)

Deriving some further results from Tensile Stability Criterion in SPH

本站小编 哈尔滨工业大学/2019-10-23

Deriving some further results from Tensile Stability Criterion in SPH

Zhengjun, YU Kai-ping, WEI Ying-Jie, ZHANG Jia-zhong

School of Astronautics,Harbin Institute of Technology,Harbin,150001,China



Abstract:

The linear form of the error propagation of SPH,which was obtained through perturbation method,has been employed to analyze the tensile instability in SPH.The sufficient condition for tensile instability,which was ever presented by Swegle,could also be derived from the eigenvalues of the linear form.Hence,the eigenvalues correspondingly yielded a tensile stability criterion.The criterion confirmed the Swegle’s statement that the tensile instability is induced by imaginary sound speed,and revealed the origins of imaginary sound speed and some details of CFL conditions.Moreover,a reasonable numerical sound speed,which accords with the one given by Monaghan through dimensional analysis,was also derived from the criterion.The kernel’s spatial derivatives,which are only with respect to the distance between particles,were found it was not accurate if the spatial derivatives of smoothing lengths were not trifle.

Key words:  SPH  tensile instability  CFL conditions  numerical sound speed  imaginary sound speed

DOI:10.11916/j.issn.1005-9113.2011.03.016

Clc Number:O302

Fund:


相关话题/Deriving some further results from