Continuous Basalt Fibers: Production aspects and Simulation of Forming Processes.
II. Optimizing the Fiber Production Technology Through Simulation of Nozzle Heat-Exchange Processes

Abstract

The methods for determining rheological and crystallization properties of basalt melts are considered. The physical properties of basalt melts suitable for the production of continuous fibers are compared with those of E-glass melts. It is established that the shape of a melt stream characterizes the area of fiber formation and depends on the production parameters and melt properties. A mathematical model is proposed to describe the features of heat exchange during slow flow of basalt melt through a short nozzle into air and during its cooling. The longitudinal temperature distribution both in the melt and in the nozzle wall is calculated for various structural and processing parameters. It is shown that the melt is cooled to the greatest extent at low flow velocities (high viscosity) in longer nozzles with a large internal diameter (small wall thickness). The results may be used to calculate melt temperature in free flowing out of the nozzle and to optimize the production of basalt continuous fibers.