Jim Day
Ansys Employee
To lessen the likelihood of improper material input, try using the PINE or FIR option for *MAT_WOOD. Predetermined properties are used with these options. If you're not already using a double precision executable of LS-DYNA, please do so. If out-of-range velocities persist, write more frequent plot states to d3plot as you approach the time at which the instability occurs. By postprocessing these more tightly bunched states, the origin and evolution of the instability may become apparent. Plotting velocities vectors can be particularly enlightening.