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We construct new first- and second-order pressure correctionschemes using the scalar auxiliary variable approach for the Navier-Stokes equations. These schemes are linear, decoupled and only require solving a sequence of Poisson type equations at each time step. Furthermore, they are unconditionally energy stable. We also establish rigorous error estimates in the two dimensional case for the velocity and pressure approximation of the first-order scheme without any condition on the time step.
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A Multirate Approach for Fluid-Structure Interac- tion Computation with Decoupled Methods
We investigate a multirate time step approach applied to decoupled meth- ods in fluid and structure interaction (FSI) computation, where two different time steps are employed for fluid and structure respectively. For illustration, the multirate technique is examined by applying the decoupled β scheme. Numerical experiments show that the proposed approach is stable and retains the same order of accuracy as the original single time step scheme, while with much less computational expense.
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- PAR ID:
- 10097721
- Date Published:
- Journal Name:
- Communications in computational physics
- ISSN:
- 1991-7120
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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