Multi-species simulation of porous sand and water mixtures
Abstract
We present a multi-species model for the simulation of gravity driven landslides and debris flows with porous sand and water interactions. We use continuum mixture theory to describe individual phases where each species individually obeys conservation of mass and momentum and they are coupled through a momentum exchange term. Water is modeled as a weakly compressible fluid and sand is modeled with an elastoplastic law whose cohesion varies with water saturation. We use a two-grid Material Point Method to discretize the governing equations. The momentum exchange term in the mixture theory is relatively stiff and we use semi-implicit time stepping to avoid associated small time steps. Our semi-implicit treatment is explicit in plasticity and preserves symmetry of force linearizations. We develop a novel regularization of the elastic part of the sand constitutive model that better mimics plasticity during the implicit solve to prevent numerical cohesion artifacts that would otherwise have occurred. Lastly, we develop an improved return mapping for sand plasticity that prevents volume gain artifacts in the traditional Drucker-Prager model.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 20, 2017
- Source ID
- 10.1145/3072959.3073651
Entities
People
- Andre Pradhana Tampubolon
- Chenfanfu Jiang
- Chuyuan Fu
- Gergely Klár
- Joseph Teran
- Ken Museth
- Theodore Gast
Organizations
- National Science Foundation
- Office of Naval Research
- United States Department of Defense
- University of California
- University of Pennsylvania