Numerical simulation of the influence of the orbiters attitude on the mu ggrowth of InP : S crystals from an In solution during the EURECA-1 flight

S-doped InP crystals were grown from an In-solution in a THM arrangement du ring the EURECA-1 mission using the automatic mirror furnace (AMF) under mi crogravity conditions. The InP-crystals showed growth rate oscillations in the range of 0.8-2.0 mu m/min with a period of 45 min, which is half the ti me of an orbit of the EURECA-1 satellite. The fluid dynamic conditions duri ng this experiment are modelled using a 3D model with the commercial softwa re FIDAP. The time-dependent simulation, considering thermal as well as sol utal buoyancy effects, indicates a weak laminar flow in this material syste m. Due to the fixed attitude of the satellite with respect to the sun the r esidual gravity vector rotates relative to the sample axis. This rotation r esults in a significant change of the residual convection level. Its maximu m is obtained, when the gravity is parallel to the growth interface (two ti mes during each orbit). Due to a high Schmidt number Sc approximate to 25 a time-dependent influence of the convection on the concentration field can also be observed. (C) 1999 Elsevier Science B.V. All rights reserved.