3.3.3. ExplicitSolver

The ExplicitSolver advances dynamics via a central-difference explicit time-integration scheme using a lumped mass matrix. It updates velocity and displacement, computes accelerations from the residual, and reports kinetic energy.

3.3.3.1. Overview

Solver type: ExplicitSolver

  • Method: explicit central differences with half-step velocity updates

  • Mass: uses lumped mass matrix from assembly

  • Loads: scalar load factor lam(t) applied to fhat

  • Termination: run stops at maxCycle

3.3.3.2. Parameters

3.3.3.2.1. Mandatory Parameters

Parameter

Description

type

Must be set to "ExplicitSolver"

3.3.3.2.2. Optional Parameters

Parameter

Description

dtime

Time step size (required for stable integration)

maxCycle

Maximum cycles to run (default: unlimited)

lam

String expression for load factor vs time, e.g., "t" or "1.0"

3.3.3.3. Algorithm Notes

  • Updates: velo += 0.5*dt*acce; disp += dt*velo; recompute f_int; compute accelerations from M_lumped acce = lam*fhat - f_int; finalize velo with half-step.

  • Sets constraint factor from current lam.

  • Prints kinetic energy periodically.

3.3.3.4. Examples

  • examples/ch05/StressWave_20x20.pro

3.3.3.5. See Also