A new enrichment space for the treatment of discontinuous pressures in multi-fluid flows

• Published in: International journal for numerical methods in fluids 2012-11, Vol.70 (7), p.829-850
• Main Authors: Ausas, Roberto F., Buscaglia, Gustavo C., Idelsohn, Sergio R.
• Format: Article
• Language: English
• Subjects: Computational methods in fluid dynamics; discontinuous pressures; Drops and bubbles; embedded interfaces; Exact sciences and technology; finite element method; Fluid dynamics; Fundamental areas of phenomenology (including applications); kinks; multi-fluids; Multiphase and particle-laden flows; Nonhomogeneous flows; Physics; surface tension; two-phase flows
• ISSN: 0271-2091; 1097-0363
• DOI: 10.1002/fld.2713

SUMMARY In this work, a new enrichment space to accommodate jumps in the pressure field at immersed interfaces in finite element formulations, is proposed. The new enrichment adds two degrees of freedom per element that can be eliminated by means of static condensation. The new space is tested and compared with the classical P1 space and to the space proposed by Ausas et al (Comp. Meth. Appl. Mech. Eng., Vol. 199, 1019–1031, 2010) in several problems involving jumps in the viscosity and/or the presence of singular forces at interfaces not conforming with the element edges. The combination of this enrichment space with another enrichment that accommodates discontinuities in the pressure gradient has also been explored, exhibiting excellent results in problems involving jumps in the density or the volume forces. Copyright © 2011 John Wiley & Sons, Ltd.