Sloshing impact response in LNG membrane carriers – a response analysis of the hull structure supporting the membrane tanks
Paper i proceeding, 2016

This study presents the determination of structural response due to sloshing impact loads in LNG carriers with membrane type cargo tanks. These loads are characterized by very short durations and are thus likely to inflict a dynamic amplification in the response of the hull. Finite element analyses are presented using a model representing parts of an LNG membrane tank. The objective was to find and quantify the dynamic amplification factor (DAF) for the structural response towards sloshing impact pressures. The influence of variations in the load characteristics such as load duration, extent of the loaded area, load location as well as the influence of the insulation system was evaluated. The study shows that the response in the studied region of the hull structure experiences significant levels of dynamic amplification during impact loads with specific durations. The response sensitivity analysis also shows that the insulation system (MARK III type) has a large effect on the dynamic behaviour of the hull structure. It has been found to alter the magnitude of the stress and deflection response for key structural members. It also changes the load time durations for which the maximum dynamic amplification occurs and increases the magnitude of the corresponding response DAF. Finally, it has been found that dynamic response gives DAF values of up to 2. The effects have been found to be present for temporal load characteristics commonly occurring in sloshing model tests and full-scale measurements and are therefore likely to occur for a vessel in operation.

dynamic amplification

LNG membrane carriers

MARK III

sloshing

impact loads

dynamic response

ABAQUS explicit

Författare

Jonas Ringsberg

Chalmers, Sjöfart och marin teknik, Marin teknik

André Liljegren

Chalmers, Sjöfart och marin teknik, Marin teknik

Ola Lindahl

Chalmers, Sjöfart och marin teknik, Marin teknik

Proceedings of the ASME 2016 35th International Conference on Ocean, Offshore and Arctic Engineering (OMAE2016) in Busan, Korea, June 19-24, 2016

Vol. 3 10-

Ämneskategorier

Maskinteknik

Farkostteknik

Styrkeområden

Transport

Materialvetenskap

Fundament

Grundläggande vetenskaper

DOI

10.1115/OMAE2016-54067

ISBN

978-0-7918-4994-1