Levelset based fluid-structure interaction modeling with the eXtended Finite Element Method

Levelset based fluid-structure interaction modeling with the eXtended Finite Element Method

Bosma, T.

Langelaar, M. (mentor)

Mechanical, Maritime and Materials Engineering

Precision and Microsystems Engineering

Engineering Mechanics

2013-12-04

This study focuses on solving steady state fluid-structure interaction (FSI) problems subjected to incompressible flow at low Reynolds numbers and linear elastic structural behavior. The fluid-structure interface geometry is described with a levelset method (LSM). The governing equations are discretized in space with the eXtended Finite Element Method (XFEM). At the fluid-structure interface, a traction and a no-slip condition are enforced to model the interaction between the two phases. Combining XFEM and LSM gives crisp and clear physical behavior at the fluid-structure interface, which is beneficial for topology optimization purposes. Two different solvers, a staggered and a monolithic solver, are used to test the accuracy of the results of the steady state solution and to check whether a numerically consistent Jacobian is built. The results show that the implementation needs to be improved in order to monolithically solve the system successfully. Finite differences are used to check the consistency of the Jacobian and show that Jacobian terms related to the levelset field are inconsistent. The proposed LSM introduces secondary coupling between neighboring elements, which is not correctly handled in the current implementation.

fluid-structure interaction
eXtended Finite Element Method
Levelset Method

http://resolver.tudelft.nl/uuid:14ec7bf9-72b4-4ff5-908e-2dc05b963360

2013-12-04

Student theses

master thesis

(c) 2013 Bosma, T.