VISCOUS DISSIPATION EFFECTS IN THE CALENDERING OF POWER-LAW FLUIDS.

Study of the temperature field of a power-law fluid for a wide range of the important processing parameters. This information is of great importance in the calendering of temperature sensitive materials such a PVC and rubbers. It is found that under certain operating conditions the temperature rise due to viscous dissipation can be high enough to be detrimental for such temperature sensitive materials as PVC and rubbers. It is important to note that the maximum exit temperature at the exit plane can be substantially smaller than the absolutely maximum temperature throughout the whole flow field. The size and location of the maxima in the temperature profiles might explain the reason for the occasional appearance of blisters in calendered sheets.