화학공학소재연구정보센터
Journal of Food Engineering, Vol.176, 56-70, 2016
Experimental analysis and numerical simulation of pasta dough extrusion process
Pasta extrusion simulation still represent a powerful challenge from a computational point of view, for both the complexity of the rheological properties of semolina dough and the process itself, in which a polymerization phenomena, driven by a combination of pressure and temperature and strongly influenced by moisture content, takes place in the final part of the extruder barrel. In this work an integrated experimental-numerical approach is proposed for numerical simulation of pasta extrusion. An extensive set of rheological data in industrial range of moisture content (MC) and temperature obtained using a capillary rheometer is reported. To overcome the reduced accuracy of Arrhenius models for pasta dough viscosity published in literature, a numerical approach based on local Taylor expansion is proposed, matching exactly experimental data. The proposed model was then validated numerically comparing numerical results obtained in the framework of Computational Fluid Dynamics with experimental data obtained by using an experimental laboratory extruder (Sercom press, mod INRA). A moving mesh approach was adopted to model the screw dynamics inside the press barrel and a modified version of OpenFoam solver was developed. Rheological test and numerical simulations reciprocally validate each others: errors in rheological characterization would results in errors in numerical results, while wrong numerical modeling would not match experimental extrusion data. The proposed tool represent a validated basis for pasta production process optimization and reverse engineering of die design. (C) 2015 Elsevier Ltd. All rights reserved.