Numerical investigation of growth interface shape and compositional distributions in SiGe crystals grown by the TLZ method in the International Space Station

•SiGe crystal growth by the traveling liquidus-zone method was carried out in ISS.•The transport phenomena and solidification were investigated by numerical simulation.•Numerical concentration distributions were coincident with the experimental results.•Axial Ge distribution became U-shaped due to the change in cartridge emissivity.•Radial Ge distributions remained relatively uniform throughout the entire crystal.