On temporal homogenization in the numerical simulation of atherosclerotic plaque growth

TL;DR

This paper extends a temporal homogenization method to fully coupled fluid-structure interaction simulations of atherosclerotic plaque growth, demonstrating its importance over simple averaging by capturing stress variations on small time-scales.

Contribution

It introduces a two-scale homogenization approach for FSI simulations of plaque growth, emphasizing the significance of small-scale stress variations.

Findings

Two-scale approach yields different results than heuristic averaging.

Periodic fine-scale problem can be solved within 2-3 heart beats.

Incorporating stress variations improves simulation accuracy.

Abstract

A temporal homogenization approach for the numerical simulation of atherosclerotic plaque growth is extended to fully coupled fluid-structure interaction (FSI) simulations. The numerical results indicate that the two-scale approach yields significantly different results compared to a simple heuristic averaging, where only stationary long-scale FSI problems are solved, confirming the importance of incorporating stress variations on small time-scales. In the homogenization approach, a periodic fine-scale problem, which is periodic with respect to the heart beat, has to be solved for each long-scale time step. Even if no exact initial conditions are available, periodicity can be achieved within only 2-3 heart beats by simple time-stepping.