POSTHARVEST BIOLOGY AND TECHNOLOGY, cilt.128, ss.83-97, 2017 (SCI-Expanded)
This study focuses on determining bruise susceptibility and the realistic representation of time-dependent nonlinear deformation behaviour of pears (Ankara variety) under various impact cases. A reverse engineering approach, physical material tests and finite element method (FEM)-based explicit dynamics simulations were utilised to investigate impact deformation characteristics of the fruit. Three impact heights (0.25, 0.5 and 1 m), three impact surfaces (steel, wood and rubber-based materials) and three impact orientations of the fruit (vertical, horizontal and at a 45 degrees angle) were considered in the impact simulation scenarios. Useful numerical data and deformation visuals were obtained from the simulation results. These results revealed that maximum bruise susceptibility magnitude on the fruit was experienced for the case of impact on the wood-based platform (impact height: 1 m; impact orientation: 0 degrees) and minimum bruise susceptibility magnitude was calculated for the case of impact on the rubber-based impact platform (impact height: 1 m; impact orientation: 45 degrees). In addition to this, numerical results related to fruit bruising were analysed through response surface analysis approach and prediction models were successfully described with a reasonable coefficient of determination (R-2) values. Verification checks of the prediction models also indicated that the relative differences between the results of simulation and the empirical model were in agreement (max. 7.03%). These models can describe the bruise susceptibility magnitudes of the fruit for various impact cases on specific impact platforms. This study contributes to further research on the usage of numerical-methods-based nonlinear explicit dynamics simulation techniques in complicated deformation and bruising investigations and industrial applications related to agricultural and food products. (C) 2017 Elsevier B. V. All rights reserved.