Premium
A linear, decoupled fractional time‐stepping method for the nonlinear fluid–fluid interaction
Author(s) -
Li Jian,
Huang Pengzhan,
Zhang Chong,
Guo Gaihui
Publication year - 2019
Publication title -
numerical methods for partial differential equations
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.901
H-Index - 61
eISSN - 1098-2426
pISSN - 0749-159X
DOI - 10.1002/num.22382
Subject(s) - mathematics , nonlinear system , mathematical analysis , fluid dynamics , convergence (economics) , time stepping , fluid–structure interaction , finite element method , mechanics , physics , discretization , quantum mechanics , economics , thermodynamics , economic growth
In this paper, a linear decoupled fractional time stepping method is proposed and developed for the nonlinear fluid–fluid interaction governed by the two Navier–Stokes equations. Partitioned time stepping method is applied to two‐physics problems with stiffness of the coupling terms being treated explicitly and is also unconditionally stable. As for each fluid, the velocity and pressure are respectively determined by just solving one vector‐valued quasi‐elliptic equation and the Possion equation with homogeneous Neumann boundary condition per time step. Therefore, the cost of the fluid–fluid interaction is dominant to solve four simple linear equations, which greatly reduces the computational cost of the whole system. The method exploits properties of the fluid–fluid system to establish its stability and convergence with the same results as the standard scheme. Finally, numerical experiments are presented to show the performance of the proposed method.