On the scale and elasticity effects in dynamic analysis of mooring lines
Due to the complexity of hydrodynamics aspects of offshore structures behaviour, experimental tests are practically compulsory in order to be able to properly evaluate and then to validate their behaviour in real sea. Moreover, the necessity to carry out hydrodynamic tests is often required by customers, classification societies and other regulatory bodies. Consequently, the correct simulation of physical properties of the complex scaled models becomes a very important issue which, sometime, is not correctly understood and applied. The present paper is trying to evaluate such kinds of problems which could arise based on some systematic tests on the dynamic behaviour of a mooring chain reproduced at five different scales. Dynamic effects as well as the influences of the elasticity simulation for 5 different scales are evaluated together. It is pointed out the necessity to pay a deeper attention to the simulation of the elasticity of coupling elements in order to ensure an acceptable level of accuracy of the experimental results. It is concluded that a much deeper investigation has to be performed.
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