Classification society Bureau Veritas (BV) and South Korean shipbuilder Hanwha Ocean have announced a Joint Development Project (JDP) on the structural assessment of independent liquified natural gas (LNG) fuel tanks for ultra-large container ships.
The JDP agreement was signed at a ceremony on 6 September at Gastech 2023 in Singapore. The project aims to enhance the design process of independent LNG fuel tanks and accelerate the development of new solutions for the structural assessment of those systems.
Today many vessels are equipped with independent tanks, either for the purpose of LNG/LPG transportation or for the use of LNG/LPG as a fuel. The particularity of these independent tanks is that they are not rigidly connected to the hull structure but are instead held by an important number of dedicated supports, which must be designed with consideration of non-linear structural response during operations, including loss of contact and sliding.
Accurately solving these contact nonlinearities usually requires large computational time, and the method is very sensitive to convergence parameters.
Recently, Bureau Veritas developed a new methodology to assess contact behaviour nonlinearities. The method was validated by comparison with simulations, and it was demonstrated that the CPU (central processing unit) time is significantly lower, while maintaining the same levels of accuracy.
The proposed solution, which has been implemented in the Bureau Veritas hydro-structure interaction suite Homer, allows for the fully consistent structural analysis of vessels equipped with independent tanks.
“Through this JDP with Bureau Veritas, it is expected that structural analysis technology will be further advanced to improve the performance of independent tanks and develop differentiated products for the application of future projects,” Joong-Kyu Kang , Head of R&D Institute of Hanwha Ocean, said.