Mathematical model of a single-screw plasticating extruder

A five zone mathematical model of a plasticating extruder is presented. Its application in the design of new and improvement of existing extruders is briefly described. The model is based on theories proposed by Darnell and Mol, Tadmor, Broyer, McKelvey, Klein, Schneider, Fenner, Poon and Jankov. A comparison between experiments and theoretical calculations is included.E energy, W - f melt film thickness, m - f_k friction coefficient - h channel depth, m - l axial screw distance, m - k power-law parameter, °C^–1 - m₀ power-law parameter, Pa sⁿ - MI melt index, g/10 min - n power-law parameter - p pressure, Pa - S screw lead, m - t temperature, °C - t_c time, s - T temperature, K - v velocity, m s^–1 - X solid bed width, m - y rectangular coordinate (channel depth direction), m - Z 1/S (turn), m^–1 - shear rate, s^–1 - apparent viscosity, Pa s - feed angle, ° - density, kg m^–3 - shear stress, Pa - a solid - b barrel or bulk - d dissipated - f flight - m melt - s screw - t total - x width channel direction - z length channel direction