There are presented some applications of parallel computers with distributed memory to solving large-scale CFD problems. Two types of flows are predicted. These are multiphase immiscible incompressible fluid flows in a porous medium and viscous compressible gas flows at low Mach number. Oil recovery problems, an isothermal lid-driven cavity flow and gas flows in a horizontal chemical reactor are considered as applications. Mathematical models as well as parallel implicit and semi-implicit algorithms are presented. Efficiency of the corresponding codes executing in different parallel environments is demonstrated.