Ship Double Bottom Construction Full Floors Design Improvement by Topology Optimization

Year 2025, Volume: 13 Issue: 2, 763 - 776, 30.06.2025

Ahmet Fatih Yılmaz

https://doi.org/10.29109/gujsc.1663786

Abstract

This study aims to reduce the structural weight of full floor elements used in commercial ship construction through topology optimization. In shipbuilding, steel plates are commonly used, and weight reduction is achieved by incorporating various openings. However, most of the existing opening designs are based on empirical standards, which are open to further optimization in terms of structural efficiency. This research proposes non-standard opening designs for full floor elements within the double bottom structures of ships with transverse framing systems, considering different widths (1.8–4.2 m) and thicknesses (10–40 mm). Using the shape optimization module of Autodesk Fusion 360 software, plate models with a height of 1200 mm were subjected to localized bottom loads. All analyses targeted a 50% reduction in structural weight. The optimization results determined the optimal number of openings and their geometric configurations for each width and thickness. Additionally, the optimized designs were evaluated through static stress analysis, identifying the maximum stress regions and their magnitudes. The findings indicate that increasing the width of the floor element results in a higher number of openings, while increasing thickness leads to larger corner radii around the openings. In all optimized models, the maximum stress value remained below the allowable limit of 150 MPa. Notably, the model with a width of 3.6 m, a thickness of 20 mm, and 50% material conservation demonstrated the most favorable structural performance. This study presents valuable insights into the structural weight reduction of full floors within ship double bottom structures through topology optimization.

Keywords

Topology optimisation, ship construction, double bottom, stress analysis

Topoloji Optimizasyonu ile Gemi Çift Dip Konstrüksiyonu Dolu Döşek Tasarım İyileştirilmesi

Abstract

Bu çalışma, ticari gemi inşasında kullanılan dolu döşek elemanlarının topoloji optimizasyonu yoluyla yapısal ağırlıklarının azaltılmasını amaçlamaktadır. Gemilerde yaygın olarak kullanılan çelik levhalar, çeşitli açıklıklar eklenerek hafifletilmektedir. Ancak mevcut açıklık tasarımlarının çoğu deneyime dayalı olup, yapısal verimlilik açısından optimizasyona açıktır. Bu araştırmada, enine sistemli bir geminin çift dip yapısındaki dolu döşek elemanları için farklı genişlik (1,8–4,2 m) ve kalınlıklarda (10–40 mm) standart dışı açıklık tasarımları önerilmiştir. Autodesk Fusion 360 yazılımının şekil optimizasyonu modülü kullanılarak, yüksekliği 1200 mm olan levha modellerine bölgesel dip yükleri uygulanmıştır. Tüm analizlerde yapısal ağırlığın %50 azaltılması hedeflenmiştir. Optimizasyon sonuçları, her genişlik ve kalınlık için optimum açıklık sayısını ve geometrik düzenleri belirlemiştir. Ayrıca, optimize edilen tasarımlar statik gerilim analizleri ile değerlendirilmiş, maksimum gerilme bölgeleri ve büyüklükleri analiz edilmiştir. Sonuçlar, döşek genişliğinin artışıyla açıklık sayısının arttığını, kalınlığın artışıyla ise açıklık kenarlarında daha geniş köşe yarıçaplarının oluştuğunu göstermiştir. Tüm optimize edilmiş modellerde, maksimum gerilme değerleri izin verilen 150 MPa sınırının altında kalmıştır. Özellikle 3,6 m genişlik, 20 mm kalınlık ve %50 malzeme korunumuna sahip modelin en uygun çözümü sunduğu belirlenmiştir. Bu çalışma, gemi çift dip yapılarında dolu döşeklerin topoloji optimizasyonu ile hafifletilmesine yönelik önemli bulgular sunmaktadır.

Keywords

Topoloji optimizasyonu, gemi konstrüksiyonu, gemi çift dip yapısı, Gerilim analizi

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