Comparisons of implicit and explicit time integration methods in finite element analysis for linear elastic material and quasi-brittle material in dynamic problems

In finite element analysis, nonlinear time-history analysis is a realistic and accurate analysis type for dynamic or seismic analysis due to its solutions contain wealthy data and complete response time-history. The most commonly used method, probably the only practical procedure, in nonlinear time-history analysis is the direct time integration...

Parameterization of Element Balance Formulation in Reactive Compositional Flow and Transport

We present a novel nonlinear formulation for modeling reactive-compositional flow and transport in presence of complex phase behavior due to combination of thermodynamic and chemical equilibrium in multi-phase systems. We apply this formulation to model precipitation/dissolution of minerals in reactive flow in subsurface reservoirs. The proposed...

A Local Time-Stepping Method for Multiphase Flow in Porous Media

Simulation of multiphase flow in natural subsurface formations include selection of time-step size, i.e., the discrete snapshots (steps) over which the time-dependent nonlinear process is investigated. The simulation results would naturally depend on the size of the discrete time step, according to the order of accuracy of the implemented...

Implicit Methods for Real-Time simulation of Interactive Waves

The project focuses on developing a simulator in which ships and waves interact. The new wave model is the Variational Boussinesq model (VBM). However, this new realistic model brings much more computation effort with it. The VBM mainly requires an unsteady state solver, that solves a coupled system of equations at each frame (20 fps) . The...

Implicit-explicit Runge-Kutta method for combustion simulation

New high order implicit-explicit Runge-Kutta methods have been developed and implemented into a finite volume code to solve the Navier-Stokes equations for reacting gas mixtures. The resulting nonlinear systems in each stage are solved by Newtons method. If only the chemistry is treated implicitly, the linear systems in each Newton iteration are...

Low Mach Number Local Preconditioning for Unsteady Viscous Finite Volumes Simulations on 3D Unstructured Grids

This paper presents a density-based finite volumes method for solving the unsteady Navier-Stokes equations on 3D unstructured grids. The second order Crank-Nicolson scheme is applied to perform the time integration. At each time step, the system of non linear equations is solved by means of a fully implicit dual time stepping method. An...

A high-order discontinuous Galerkin solver for 3D aerodynamic turbulent flows

This paper deals with the evaluation and validation of a recently developed parallel discontinuous Galerkin code for the numerical solution of the RANS and k-omega turbulence model equations. The main features of the code can be summarized as follows: a) high-order spatial accuracy on hybrid grids, b) fully coupled, implicit time discretization,...