On the Cooling of Fibers

The effects of the stretching of filaments on the cooling of fibers during the melt-spinning process are studied numerically. The filament is modeled as a continuous, cylindrical cone that moves steadily through an otherwise quiescent environment, with its diameter attenuating exponentially. Radiative cooling from the fiber surface is also accounted for in the analysis. The buoyancy-affected laminar and turbulent boundary layer equations are solved by a finite difference scheme, to determine the axial temperature variation of the filament. It is found that the reduction of the fiber diameter and the subsequent increase in the local speed of the filament enhances greatly the cooling from the filament surface, whereas the increase of the cooling due to radiative losses is not significant for all the flow cases considered.