JOURNAL OF FOOD PROCESS ENGINEERING, cilt.41, sa.7, 2018 (SCI-Expanded)
Realistic representation of time-dependent internal stress progression and deformation behavior of a potato tuber during a sample drop case has been studied in this article. A reverse engineering approach, compressive tests, slow motion camera records and finite element analysis (FEA) were employed to analyze the drop case deformation behavior of a sample potato tuber. Simulation results provided useful numerical data and stress distribution visuals. The numerical results are presented in a format that can be used for the determination of bruise susceptibility magnitude on solid-like agricultural products during drop case. The visual observations revealed that slow motion camera images and simulation printouts were in good correlation. The modulus of elasticity of the potato specimens was calculated from experimental data to be 3.12 MPa and simulation results showed that the maximum equivalent stress was 0.526 MPa on the tuber. This value for stress indicates that bruising is not likely on the tuber under a pre-defined drop height. In order to test the simulation accuracy, empirical, and simulation-based estimates for total energy in this drop case were compared. The relative difference between empirical and simulation results was 1.27%. This study provide a good "how to do" guide to further research on the utilization of (FEM)-based time-dependent simulation approach in complex mechanical impact based damaging analyses and industry focused applications related to solid-like agricultural products such as potato. Practical applications The engineering simulation based "how to do" pathway presented in this study is a scientific novelty because the explicit dynamics simulation technique for potato tuber damage under drop case and its visual verification has been limitedly introduced in the literature. This study present deeper analysis on material model description, slow motion camera records, time dependent non-linear stress analysis and FEM based Explicit Dynamics Simulation procedures. This study aims to represent a realistic non-linear deformation case of the tuber which is very complicated to obtain through physical and/or empirical expressions. As a further step from other literature studies, this research has presented a novel realistic time-dependent non-linear drop test simulation based on physical compressive material test data. The findings have been prepared in a form which may be used as input parameters in design studies for solid-like agricultural products (such as potato tubers) processing machinery systems used in food/agricultural industries.