Abstract: The growth process of industrial 8 inch single crystals issimulated by FLUTRAP(fluid flow and transport phenomena program), which isbased on non-orthogonal grid and finite-volume method. The results show thatthe flow field inside the crucible and the pulling rate are oscillating duringthe growth processes. The pulling rate is fluctuating with a period of about 2minutes. The fluctuation amplitude of the pulling rate could be reduced byapplying a cusp magnetic field.