Numerical calculations of the air flow and heat transport processes in film blowing have been made, considering the turbulence of the air flow. The parameters air mass now, air temperature, air velocity, and angle-of-attack have been varied. The results have shown that the air massflow has the strongest influence on cooling in tile processing window examined. So the massflow is a very efficient actuator of a film thickness control system. Moreover, the angle-of-attack together with the bubble shape is responsible for the occurrence of vortices. Such vortices can be the reason for unstable behavior in the bubble forming zone and hence for increased thickness tolerances of the film.