A compacted bentonite clay buffer is planned to be used as a part of the engineered barrier system in the KBS-3 concept for the disposal of spent nuclear fuel. Simulations together with experimental studies are needed to ensure that bentonite fulfills its safety functions in the concept. In this paper, one type of bentonite model, namely a thermomechanical model developed by Petri Jussila, is presented in brief and its numerical implementation with COMSOL Multiphysics 4.0a is discussed. The model describes bentonite as a mixture of four components: solid skeleton, liquid water, water vapour, and air. The system is defined by basic balance laws along with the somewhat complex constitutive equations that are based on a thermomechanical approach. Previously, the model has been implemented with software called Elmer by CSC - IT Center for Science and with an in-house code Numerrin by Numerola Oy that has made some extensions to the model.
|Title of host publication||COMSOL Conference 2010 Paris|
|Subtitle of host publication||User presentations and proceedings|
|Number of pages||7|
|Publication status||Published - 2010|
|MoE publication type||B3 Non-refereed article in conference proceedings|
Pulkkanen, V-M., & Olin, M. (2010). Numerical implementation of a multivariable thermomechanical model for unsaturated bentonite. In COMSOL Conference 2010 Paris: User presentations and proceedings COMSOL. https://www.comsol.de/paper/download/63561/pulkkanen_paper.pdf