NUMERICAL SIMULATION OF DOUBLE ROLL EXTRUSION OF BISCUIT DOUGH BASED ON SLIP BOUNDARY CONDITIONS

Biscuits are one of the most popular snacks, and the mass production of biscuit dough requires the extrusion weight of each dough to remain stable and consistent. The biscuit dough is a non-Newtonian fluid. The Polyflow software was used to simulate the biscuit dough extrusion process in a double-roller extruder. The relationship between the slip coefficient and the roller speed, and the uniformity of the outlet flow rate of the biscuit dough were analyzed. The results showed that the dough outlet flow rate was ununiform. For the five outlet orifices configuration, the extrusion mass flow rate on both sides was lighter than that inside. The slip coefficient increased linearly with the roller rotation speed. Numerical simulation can predict the average extrusion mass flow rate, and the prediction accuracy does not decrease with the increase of the rotational speed.