Effect of roof impacts on coupling between wave response and sloshing
in tanks of LNG-carriers
B. Molin, F. Remy (Ecole Centrale Marseille)
A. Ledoux, N. Ruiz (Principia)
Experimental and numerical roll RAOsIrregular sea-state Tp=1.6s, Hs=0.034m.
Tanks 1 and 2: 19cm Tank 1: 39cm. Tank 2: 19cm.
ROOF AT FREE SURFACE. ADJUSTMENT OF ROLL VISCOUS COEFFICIENT
HS = 6 cm
ROLL RAO
ROOF AT FREE SURFACE. ADJUSTMENT OF ROLL VISCOUS COEFFICIENT
HS = 12 cm
ROLL RAO
FLAT ROOF 16 cm ABOVE FREE SURFACE. HS = 6 cm, TP = 1.6 s (NO IMPACTS)
ROLL RAO
FLAT ROOF 16 cm ABOVE FREE SURFACE. HS = 6 cm, TP = 1.6 s (NO IMPACTS)
RAO OF THE FIRST SLOSHING MODE
FLAT ROOF 16 cm ABOVE FREE SURFACE. HS = 6 cm, TP = 1.6 s (NO IMPACTS)
RAO OF THE THIRD SLOSHING MODE
FLAT ROOF 16 cm ABOVE FREE SURFACE. HS = 12 cm, TP = 1.6 s (A FEW IMPACTS)
ROLL RAO
FLAT ROOF 16 cm ABOVE FREE SURFACE. EXPERIMENTAL RAOS OF THE FIRST
SLOSHING MODE HS = 6, 9, 12 cm TP = 1.6 s
EXPERIMENTAL ROLL RAOSFLAT ROOF AT 16, 11, 5 cm.
HS = 12 cm TP = 1.6 s
HS = 6 cm
CHAMFERED ROOFS
MESH FOR DIOCUVE
EXPERIMENTAL ROLL RAOSFLAT VS. CHAMFERED 16 cm ABOVE F.S.
HS = 6 cm TP = 1.6 s
EXPERIMENTAL AND NUMERICAL ROLL RAOSFLAT VS. CHAMFERED 16 cm ABOVE F. S.
HS = 6 cm TP = 1.6 s
FLAT
EXPERIMENTAL AND NUMERICAL ROLL RAOSCHAMFERED ROOF 16 cm ABOVE F. S.
HS = 12 cm TP = 1.6 s
EXPERIMENTAL AND NUMERICAL ROLL RAOSCHAMFERED ROOF 11 cm ABOVE F. S.
HS = 6 cm TP = 1.6 s
EXPERIMENTAL AND NUMERICAL ROLL RAOSCHAMFERED ROOF 11 cm ABOVE F. S.
HS = 12 cm TP = 1.6 s
Conclusions
• Roof impacts do not seem to affect the roll response much
• Free surface non-linearities play a major role
• Chamfers effective by reducing free surface length
• Exploitation of test data still incomplete (roof impact loads)
FLAT ROOF 11 cm ABOVE FREE SURFACE