26 March 2025 – ClassNK has released benchmark tank test data that can be used as validation data for ‘direct load analysis programs’ to support the development of new vessel types, such as ultra-large container ships and alternative fuel vessels. ‘Direct load analysis’ is an advanced approach to hull strength assessment in cases where simplified formulae are not applicable due to novel hull shapes or sizes. By establishing these data as a common reference between the shipyard and ClassNK, the reliability and transparency of the analytical basis will be enhanced, leading to faster and smoother design approval.
The Guidelines for Direct Load Analysis and Strength Assessment outline the requirements for conducting direct load analysis, enabling highly accurate strength assessments based on the specific loading characteristics of vessels with new structural configurations or unprecedented sizes.
The accuracy of direct load analysis depends on the quality of the program input data, which can vary. To ensure a more accurate calculation of the loads acting on actual vessels, ClassNK has conducted large-scale tank tests using state-of-the-art equipment and has made benchmark test data publicly available. The benchmark data cover two key ship types*1 – a large container ship and an oil tanker – and provide design data such as hull shape and weight distribution, as well as experimental results like ship motions and accelerations. These datasets, representing both slender and fuller hull forms, can be widely applied to various vessel types and related technological developments.
With the data release, ClassNK has updated its ‘Guidelines for Direct Load Analysis and Strength Assessment’ to version 4.0 and introduced new requirements recommending comparison and verification with these benchmark data to validate the accuracy of analysis programs.
Through ongoing research, development, and knowledge sharing, ClassNK remains committed to contributing to a more sustainable future.
Benchmark data are available on request from the ‘ClassNK Open data’ page (https://www.classnk.or.jp/classnk-rd/randd/opendata.html) on the ClassNK Research Institute website.
The guidelines are available to download via ‘Guidelines’ of My Page on ClassNK’s website after registration.
https://www.classnk.or.jp/account/en/Rules_Guidance/ssl/guidelines.aspx
*1 Container ship: NK-14KTEU
Oil tanker: NK-VLCC
