Comparing multi-index stochastic collocation and multi-fidelity stochastic radial basis functions for forward uncertainty quantification of ship resistance

Abstract This paper presents a comparison of two multi-fidelity methods for the forward uncertainty quantification naval engineering problem. Specifically, we consider problem quantifying hydrodynamic resistance roll-on/roll-off passenger ferry advancing in calm water and subject to operational uncertainties (ship speed payload). The first four statistical moments (mean, variance, skewness, kurtosis), probability density function such quantity interest (QoI) are computed with methods, i.e., Multi-Index Stochastic Collocation (MISC) an adaptive Radial Basis Functions (SRBF). QoI is evaluated via computational fluid dynamics simulations, which performed in-house unsteady Reynolds-Averaged Navier–Stokes (RANS) multi-grid solver $$\chi$$ χ navis. different fidelities employed by both obtained stopping RANS at grid levels cycle. performance presented discussed: nutshell, findings suggest that, least current implementation MISC could be preferred whenever limited budget available, whereas larger SRBF seems preferable, thanks its robustness numerical noise evaluations QoI.