Theoretical analysis of force, pressure and energy distributions of bulk oil palm kernels along the screwline of a mechanical screw press FL 200
¹Czech University of Life Sciences Prague, Department of Mechanical Engineering, Faculty of Mechanical Engineering, Kamycka 129, CZ165 00 Prague, Czech Republic
²Czech University of Life Sciences Prague, Department of Material Sciences and Manufacturing Technology, Kamycka 129, CZ165 21 Prague, Czech Republic
*Correspondence: kabutey@tf.czu.cz
Abstract:
The present study is a follow-up of the previously published study on the mathematical description of loading curves and deformation energy of bulk oil palm kernels under compression loading, aimed at determining theoretically the amounts of force, pressure and energy along the screw lamella positions ??? of the screw press FL 200 by applying the tangent curve mathematical model and the screwline geometry parameters (screw shaft diameter, screw inner and outer diameters, screw pitch diameter and the screw thickness). The fitting curve value ?? of the tangent mathematical model was further examined at ?? = 2 and ?? = 3 by identifying the force, deformation, stress and compression coefficients at varying vessel diameters ?? and initial pressing heights ?? of the bulk oil palm kernels. Based on the results of the stepwise regression analysis, the amounts of the theoretical deformation energy ??? in linear pressing as well as the theoretical force ??, pressure ?? and energy ??? of the screw press FL 200 were statistically significant (P-value < 0.05) or (F-value > significance F) in relation to the predictors (??, ??, ?? and ???). The coefficient of determination (R2) values between 61 and 86 % were observed for the determined regression models indicating that the responses ???, ??, ?? and ??? can accurately be predicted by the corresponding predictors. The normal probability plots of the responses approximately showed a normal distribution.
Key words:
compression loading, experimental data, mathematical model, responses and predictors, screw geometry parameters