Andersen, Ingrid Marie Vincent3; Jensen, Jørgen Juncher1; Nielsen, Ulrik Dam1
1 Department of Mechanical Engineering, Technical University of Denmark2 Fluid Mechanics, Coastal and Maritime Engineering, Department of Mechanical Engineering, Technical University of Denmark3 Coastal, Maritime and Structural Engineering, Department of Mechanical Engineering, Technical University of Denmark
This paper deals with the analysis of recent full-scale strain measurements in the hull of a large container carrier covering several months of operation. The focus is on the real-time prediction accuracy of responses 5-15 seconds ahead of the measurements. Such results are less applicable in the operation of container carriers but are important in e.g. loading/unloading operations at sea or helicopter landings. Three different procedures are discussed: Conditional processes with analytical estimates of the mean values and standard deviations, the autoregressive predictor method and a method based on superposition of sinus-oidal components. The conditional processes do not need offline training and will be applied to measured time series in order to evaluate the accuracy of response predictions within the next 1-30 seconds. The number of measured points and the time distances between them are varied to determine the best solutions. A procedure based on 11 measured points spaced 1 sec, covering the last 10 sec of the instantaneous measured signal seems generally able to give fair predictions up to 5-10 sec ahead of the current time. The full-scale data is provided through the EU FP7 project Tools for Ultra Large Container Ships (TULCS) project no. 234146.
Proceedings of the Prads 2013, 2013
Main Research Area:
12th International Symposium on Practical Design of Ships and Other Floating Structures, 2013