Lu, Y, Sok, T, Scott, J & Gilbert, C 2026, 'A fluid–structure interaction study of upset load from material build-up in raked thickeners', in AB Fourie, M Horta, M Oliveira & S Wilson (eds), Paste 2026: Proceedings of the 28th International Conference on Paste, Thickened and Filtered Tailings, Australian Centre for Geomechanics, Perth, pp. 1-15, https://doi.org/10.36487/ACG_repo/2655_50
(https://papers.acg.uwa.edu.au/p/2655_50_Lu/)
Abstract: Raked thickeners are critical to mineral processing, yet their design often relies on empirical correlations that fail to predict transient upset loads, leading to over-design or catastrophic mechanical failures. This study presents a high-fidelity, one-way fluid–structure interaction (FSI) framework to quantify transient rake loads induced by extreme material accumulation (island formation) on the floor of a 45 m industrial deep-cone thickener. Transient computational fluid dynamics (CFD) simulations were utilised to model non-Newtonian slurry dynamics and map hydraulic pressure and shear-stress distributions directly onto a finite element analysis (FEA) structural model. Two worst-case upset scenarios were evaluated: an inner island engaged by both short and long rake arms, and an outer island engaged exclusively by the long arm. Results demonstrate that outer island formation induces up to an 88% increase in rotational torque and a 593% increase in nonrotational forces compared to normal steady-state operation. Despite peak rotational torques reaching 366,951 N·m, structural stresses remained below 66 MPa, well within the yield limits of standard structural steels. The findings highlight that while island-induced loads do not immediately threaten structural integrity, the resulting asymmetric forces and severe torque spikes are critical sizing parameters for drive systems and operational control strategies.

Keywords: raked thickener, mineral processing, normal load, upset load, fluid–structure interaction