OpenFDEM#
Open-Source Finite and Discrete Element Solver
Copyright (©) 2017 - 2026 by Dr. Xiaofeng Li.
What is OpenFDEM#
OpenFDEM is a free and open finite-discrete element simulation framework for accurately and efficiently solving diverse multiscale, multiphase, and multiphysics (3M) problems. Based on the Finite-Discrete Element Method (FDEM) , OpenFDEM integrates advanced numerical methods, including the Material Point Method (MPM), Phase-Field Method (PFM), and Finite Difference Method (FDM), to simulate complex problems involving solid mechanics, fluid dynamics, heat transfer, and their coupled processes. Developed in C++, OpenFDEM provides flexible modules for geometry, mesh, and material management. It is widely applicable to fracture, fragmentation, impact, fluid-solid interaction, and large-deformation problems.
Introduction to FDEM#
FDEM is a hybrid numerical method that combines the advantages of the Finite Element Method (FEM) and the Discrete Element Method (DEM). Similar to FEM, FDEM describes the deformation of continuous media through spatial discretization and differential equations. Meanwhile, it incorporates DEM-based contact detection and contact force calculation algorithms to simulate interactions between separated bodies. Unlike conventional hybrid methods, discrete elements in FDEM are generated naturally after the failure of continuous elements. Therefore, the transition from a continuous state to a fractured and fully fragmented state occurs automatically during the simulation process.
Benefiting from this unique capability, FDEM can realistically reproduce the complete failure process of brittle materials, including elastic deformation, crack initiation, crack propagation, fragmentation, and post-failure motion, making it suitable for simulations of materials such as glass, rocks, ceramics, and concrete.
Figure 1. Glass fragmentation in reality.
Figure 2. Simulation of glass fragmentation (Left: continuous method; Middle: continuum damage method; Right: FDEM simulation).
Applications of OpenFDEM#
Underground Excavation
OpenFDEM can simulate excavation and blasting processes in underground engineering, including stress wave propagation, crack growth, fragmentation, and rock mass failure. By considering material heterogeneity and damage evolution, OpenFDEM helps analyze excavation-induced damage and optimize engineering designs.
Figure 3. Tunnel excavation simulations (static / dynamic / drill-and-blast).
Fluid-Solid Coupling
OpenFDEM can simulate complex fluid-solid interaction problems, such as seepage-induced failure, tunnel water inrush, and underground storage leakage. By coupling solid deformation with fluid flow, it enables the analysis of hydro-mechanical processes and related geological hazards.
Figure 4. Tap water flow into a tank.
Granular Flow and Particle Dynamics
OpenFDEM is suitable for simulating granular materials, including particle flow, deposition, crushing, and rearrangement processes. The explicit treatment of particle interactions makes it applicable to high-density granular systems and particle-structure interaction problems.
Figure 5. Landslide simulation.
Impact and Dynamic Loading
OpenFDEM can reproduce material responses under high-rate loading conditions, including stress wave propagation, dynamic fracture, and fragment generation. It is applicable to impact, blast, and penetration problems for analyzing failure mechanisms of materials and structures.
Figure 6. Impact simulation.
Large Deformation Problems
OpenFDEM provides robust solutions for large-displacement and strongly nonlinear problems involving severe deformation and contact evolution. It can be applied to landslides, ground deformation, and soft soil settlement simulations.
Figure 7. Large deformation.
Complex Contact Problems
OpenFDEM is capable of handling complex contact interactions, including sliding, separation, fracture, and interface debonding. It is suitable for studying rock block movement, structural failure, and composite material interface damage.
Figure 8. Complex interface contact simulation (left) and dynamic updating of contact lists (right).