3-D high-fidelity hydrostructural optimization of cavitation-free composite lifting surfaces. (15th July 2021)

• Record Type: Journal Article
• Authors: Liao, Yingqian; Martins, Joaquim R.R.A.; Young, Yin Lu
• Is Part Of: Composite structures. Volume 268(2021)
• Publication Date: 2021-07-15
• Subjects: Composite structures -- Hydroelasticity -- Fluid–structure interaction -- Anisotropy -- Cavitation -- Bend-twist coupling; Composite construction -- Periodicals; Composites -- Périodiques; 624.18
• DOI: 10.1016/j.compstruct.2021.113937
• Languages: English
• ISSNs: 0263-8223

Abstract

Abstract: Design and manufacturing technologies have promoted the use of composites in hydrodynamic lifting surfaces. Composites, even with state-of-the-art coatings, are susceptible to cavitation erosion damage. This work aims to design a cavitation-free composite lifting surface to maximize efficiency while ensuring structural integrity. We optimize a canonical hydrofoil using a gradient-based optimization framework that couples a Reynolds-averaged Navier–Stokes solver with a finite-element structural solver. The optimization reduces the weighted drag coefficient by 1.2% over lift coefficients between 0.2 and 0.6, and increases the cavitation inception speed by 82% at the nominal condition compared to the baseline. The optimized design shows higher cavitation inception speeds than an Eppler hydrofoil (E1127, known for cavitation-free operation at moderate lift conditions) with the same baseline planform at C L ≥ 0.2 . The improvement from the E1127 hydrofoil was due mostly to delaying tip vortex cavitation induced by 3-D effects. The optimization finds the fiber angle to balance the bend-twist coupling and modifies the directional strength to reduce the susceptibility to excessive deformation and material failure when sweep presents.