Study of the crumpling conditions of carrot top residues on the root crown under impact contact of a cleaning bladeand determination of the mass of removed residues

V. Bulgakov¹, M. Budzanivskyi², I. Holovach¹, Ye. Ihnatiev³⁴ and J. Olt³*

¹National University of Life and Environmental Sciences of Ukraine, 15 Heroyiv Oborony Str., UA 03041 Kyiv, Ukraine
²Institute of Mechanics and Automatics of Agroindustrial Production of the National Academy of Agrarian Sciences of Ukraine, 11/1 Vokzalna Str., UA 08631 Hlevakha, Ukraine
³Estonian University of Life Sciences, Institute of Forestry and Engineering, 56 Kreutzwaldi Str., EE 51006 Tartu, Estonia
⁴Dmytro Motornyi Tavria State Agrotechnological University, 66 Zhukovsky Str., UA 69600 Zaporizhzhia, Ukraine
*Correspondence: jyri.olt@emu.ee

Abstract:

Effective removal of carrot top residues is essential for marketable root quality, while excessive blade impact can increase crop damage and harvesting losses. The aim of this study was to estimate the mass (M_cr) of carrot top residues removed from the root crown by a flexible cleaning blade after impact contact, and to analyse the sensitivity of the model to the kinematic and design parameters of the cleaner. The study combined a criterion for residue weakening during impact with a simplified model of post-impact removal. Literature data on carrot crown geometry and crop mechanical properties were used together with the design parameters of a two-shaft cleaner. The developed model was analysed for ω = 10–50 rad s^–1, ρ = 0.06–0.12 m, b = 0.03–0.06 m and δ_cr = 0.002–0.005 m. Because values of the effective bulk density of the compacted top-residue layer and its thickness after impact were not found in the literature, ρ_h = 850 kg m^–3 and t_imp = 0.008 s were assumed for modelling, whereas δ_cr was varied within an engineering range. At the initial values ω = 30 rad s^–1, ρ = 0.10 m, b = 0.04 m and δ_cr = 0.004 m, the predicted mass removed in one blade pass was 3.264 g. The constructed response surfaces showed a monotonic increase of M_cr with all variables; within the selected limits, M_cr ranged from 0.65 to 6.53 g for the pair (ω, ρ) and from 1.22 to 6.12 g for the pair (b, δ_cr ). The calculated initial residue mass on the carrot crown of 13.86 g indicates that a blade pass can remove about 23.5% of the nominal load, which supports the use of multi-blade cleaners and two parallel shafts.

Key words:

coefficient of restitution, elastic blade, kinematic parameters, post-impact removal, response surface analysis, two-shaft cleaner