Abstract: The die rheometer is utilized to investigate the in-line rheological behaviors of CDA solution, as the substitute of NC, in extrusion processing. The experimental results demonstrate that CDA solution is a non-Newtonian pseudoplastic fluid, and the increase in processing temperature is in favor of improving the rheological behaviors of CDA solution. The finite element software Polyflow is provided for the numerical simulation of CDA solution in the die to get the distribution of pressure, shear rate and shear viscosity. A power model is applied as the constitutive equation. The data calculated by the numerical simulation is close to the results obtained from the experiment. Polyflow indicates that the higher screw speed not only decreases the viscosity but also increases the pressure and pressure drop rate which is disadvantageous to the quality and processing security of propellants. The experiment and numerical simulation of the in-line rheological behaviors of CDA solution have the guiding significance for the continuous processing of gun propellants.

Key words: ordnance science and technology, cellulose acetate, shear viscosity, pressure, Polyflow