Finite Element Model Updating of a Scale Model Ship Using Experimental Modal Analysis and Response Surface Methodology

Abstract

The structural dynamics of scale model ships used in towing tank experiments may affect the measured values of propeller-induced pressure fluctuations. The International Towing Tank Conference (ITTC) recommends monitoring structural responses during the tests to evaluate this effect but does not provide a specific procedure for such monitoring. Apart from considering structural behavior during towing tests, having a reliable numerical model of the scale model ship structure is essential to be aware of its vibratory behavior not only prior to lab experimentation to control experimental errors but also when replacing costly physical experiments with cost-effective computational simulations. To address this, we generate a finite element (FE) model of the scale model ship used in our towing tests. We present a methodology for characterizing this FE model based on the physical model’s behavior to ensure its reliability for further numerical dynamic analyses. The properties of the FE model are updated by using response surface methodology (RSM) to align numerical and experimental resonance responses. Latin hypercube sampling (LHS) technique is employed to generate the design space, whereas the modal assurance criterion (MAC) serves as a performance metric to ensure modal consistency before and after optimization. This approach provides a reliable FE model that offers a cost-effective alternative to expensive physical tests for enhancing the precision of propeller-induced pressure measurements.

Keywords

Scale model ship / Finite element model update / Propeller-induced pressures / Latin hypercube sampling / Response surface methodology

RIGHTS & PERMISSIONS

Harbin Engineering University and Springer-Verlag GmbH Germany, part of Springer Nature