  By using the finite element code ASTRA, the effect of vibrations on the melt
flow in Bridgman crystal growth is investigated for the Earth and Space gravity
conditions. It is found that the vibrations significantly decrease the width of
interfacial boundary layers in Bridgman crystal growth with submerged vibrator.
The influence of the geometrical arrangement of the vibrator, the
thermo-gravitational conditions, the frequency of vibration and the rotation
effects is investigated. The averaged vibrational flow (AVF) parameters were
calculated by means of post-processing the instant thermomechanical fields
found in numerical integration of Navier-Stokes problem. The structure of AVF
depends on the physical properties of the melt and on the frequency/amplitude
values. The frequency of vibrations (vibrational Reynolds number) influences
essentially on the AVF structure. Numerical results show that the direction of
AVF depends with frequency. It is shown that for normal and low gravity
conditions the vibrations can decrease the width of boundary layers and
increase the boundary temperature gradients. This can intensify heat and mass
transfer near the solid-liquid interface and increase the rate of crystal
growth.
