- Sponsor
- Department of Civil and Environmental Engineering
- Originating Calendar
- CEE Seminars and Conferences
Computational Methods for Interface-coupled Multiphysics Problems
Advisor: Associate Professor Jinhui Yan
Abstract
Characterized by the interaction of distinct physical processes across reduced-dimension
interfaces or thin buffer regions, interface-coupled multiphysics systems represent a fundamental
class of problems in science and engineering. When applied to these problems, conventional
numerical methods often encounter significant difficulties, including labor-intensive mesh
generation and remeshing, degraded interfacial resolution, and poor convergence behavior. These
challenges are rooted primarily in two inherent features of interface-coupled multiphysics
systems: the need for flexible and robust mesh management and the strong coupling of physical
processes through interface conditions with simultaneous continuity of solution fields and fluxes.
This dissertation develops effective and robust computational strategies to address these
challenges for interface-coupled multiphysics problems. For scenarios in which mesh
management is particularly challenging due to complex geometry, interface motion, or
topological change, an enriched immersed boundary method is proposed. The method augments
the approximation space in interface-cut elements to enforce continuity of solution fields and
fluxes while retaining the mesh flexibility of traditional immersed boundary approaches. As a
result, it enables reliable simulation of conjugate heat-transfer problems with large materialproperty
contrasts, but avoids the need for boundary-fitted meshes or frequent mesh regeneration.
For problems in which resolution requirements of interfacial physics exceeds the capabilities of
immersed boundary approaches, this dissertation further develops an overset-mesh-based
coupling framework combined with Schwarz alternating methods. This approach preserves
explicit interface representations and allows high-resolution treatment of near-interface regions.
Due to the convergence limitations of iterative Schwarz coupling for strongly coupled or
nonlinear problems, a monolithic inter-domain coupling formulation is subsequently introduced.
By embedding inter-subdomain interactions directly into the global nonlinear system, the
monolithic framework significantly improves convergence robustness and maintains the
flexibility of independent mesh motion among substructures.
The proposed methods are validated through a series of numerical investigations ranging from
canonical benchmark problems, such as one-dimensional Burgers’ equations and spherical heatconduction
tests, to large-scale three-dimensional applications including gas and water
quenching processes and bio-inspired flier dynamics. These studies demonstrate the numerical
stability, convergence, and extensibility of the proposed frameworks, highlighting their capability
to address realistic and challenging interface-coupled multiphysics problems encountered in
engineering practice.