Adjoint node-based shape optimization of free-floating vessels
نویسندگان
چکیده
Abstract The paper is concerned with a node-based, gradient-driven, continuous adjoint two-phase flow procedure to optimize the shapes of free-floating vessels and discusses three topics. First, we aim convey that elements Cahn–Hilliard formulation should augment frequently employed Volume-of-Fluid model maintain dual consistency. It seen such consistency serves as basis for robust primal/adjoint coupling in practical applications at huge Reynolds Froude numbers. second topic covers different strategies. A central aspect application floating position, particularly trim sinkage, interact variation hydrodynamic loads induced by shape updates. Other topics addressed refer required level density more straightforward—yet non-frozen—adjoint treatment turbulence. third part computation descent direction within node-based environment. We will illustrate means deform both volume mesh hull simultaneously same time obey technical constraints on vessel’s displacement its extensions. Hilbert-space approach provides smooth updates using established coding infrastructure computational fluid dynamics algorithm access managing additional constraints. Verification validation follow from submerged 2D cylinder case. includes full-scale offshore supply vessel $$\mathrm{Re} = 3 \times 10^8$$ Re = 3 × 10 8 $$\mathrm{Fn} 0.37$$ Fn 0.37 . Results fully parallel can automatically reduce drag an already pre-optimized 9–13% $$\approx\,{\mathcal{O}}$$ ≈ O (10,000-30,000) CPUh depending considered couplings floatation aspects.
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ژورنال
عنوان ژورنال: Structural and Multidisciplinary Optimization
سال: 2022
ISSN: ['1615-1488', '1615-147X']
DOI: https://doi.org/10.1007/s00158-022-03338-2