Dynamic Tension On Mooring Lines. Comparison of Numerical And Experimental Results.

This paper presents experimental results on tensions induced on a mooring line model by harmonic motions imposed at its top. The results were obtained in towing -tank tests and include current effects on the line and different combinations of amplitude and frequency of top motion. The tests were performed for validation of the finiteelement model included in the University of Sao Paulo Numerical Offshore Tank. The small-scale model consists of a chain – steel wire rope – chain line, which was towed along the tank in order to emulate the action of a uniform current profile. Tension at the top of the line was measured by means of a load cell and results are compared to those predicted according to the FEM model. Agreement between numerical and experimental results demonstrates that the numerical code is able to fairly reproduce the dynamic tension along the line even for high values of amplitude and frequency of top motions.