  A small, spherical bubble of high internal pressure is inserted into water at
constant ambient pressure as a model of a laser-induced bubble. Its subsequent
dynamics near a flat solid boundary is studied in dependence on the distance of
the bubble to the boundary by numerically solving the Navier-Stokes equations
with the help of the open source software environment OpenFOAM. Implemented is
the finite volume method for discretization of the equations of motion and the
volume of fluid method for capturing the interface between the bubble interior
and exterior. The bubble contains a small amount of non-condensable gas that is
treated as an ideal gas. The liquid is water obeying the Tait-equation. Surface
tension is included where necessary. The evolution of the bubble shape and a
selection of pressure and velocity fields are given for normalized distances
$D^* = D/R_{\rm max}$ between 0 and 3 ($D$ = initial distance of the bubble
centre to the boundary, $R_{\rm max}$ = maximum radius the bubble would attain
without any boundary). $R_{\rm max} = 500 \mu$m is chosen for the study. Normal
axial jet formation ($\sim 100$ m s$^{-1}$) by axial flow focusing is found for
$0.24 \le D^* \le 3$ and the change to a different type of axial jet formation
($\sim 1000$ m s$^{-1}$) by annular-liquid-flow collision for bubbles very near
to the solid boundary ($0 \le D^* \le 0.2$). The transition region ($0.2 < D^*
< 0.24$) is characterized by additional inbound and outbound annular jets.
Remarkably, the inclusion of the viscosity of the water is decisive to get the
fast jets.
