Topology optimization for fluid-structure interaction with precise evolving boundaries using iso geometric analysis

Topology optimization for fluid-structure interaction with precise evolving boundaries using iso geometric analysis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Topology optimization for fluid-structure interaction with precise evolving boundaries using iso geometric analysis Majd Kosta, Oded Amir This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8691556/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 8 You are reading this latest preprint version Abstract We present a novel body-fitted iso geometric topology optimization framework for fluid–structure interaction problems. Using a spline-based parametric representation of the fluid and solid domains as well as their interface, the method enables consistent evaluation of flow and structural quantities on geometrically accurate boundaries throughout the optimization process. When verified on various benchmark problems, the underlying iso geometric analysis exhibited higher accuracy and superior convergence rates in comparison to standard finite element methods. A shape optimization stage is introduced after the optimized topology is obtained, alleviating geometric artifacts arising from trimming and untrimming operations and reducing computational effort while preserving geometric smoothness and convergence. Several numerical examples demonstrate the capabilities of the framework to optimize fluid-structure interactions involving challenging functionals such as lift, drag, pressure drop, interfacial stress and fluid-to-solid traction distribution. Overall, the framework provides an accurate and physically consistent approach for shape and topology optimization in fluid–structure interaction systems. Topology optimization Fluid-structure interaction Iso geometric analysis Body-fitted discretization Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 05 May, 2026 Reviews received at journal 30 Mar, 2026 Reviewers agreed at journal 20 Mar, 2026 Reviewers agreed at journal 18 Mar, 2026 Reviewers invited by journal 17 Mar, 2026 Editor assigned by journal 27 Jan, 2026 Submission checks completed at journal 26 Jan, 2026 First submitted to journal 25 Jan, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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