Experimental evaluation of slamming pressure models used in structural design of high-speed craft

摘要

In this paper a methodology that enables detailed studies of the momentary slamming pressure distribution and the related structural loads is presented. The methodology involves pressure measurements, spatial and temporal pressure distribution reconstruction, and finite element analysis. Using a set of model experiments with a high-speed planing craft towed in irregular waves, the methodology is applied to evaluate different slamming pressure models regarding their ability to accurately represent the structure loads. The slamming equivalent uniform pressure model used in the prevailing semi-empirical design methods, and non-uniform time-dependent pressure models used in a method for direct calculation, are considered. It is concluded that for smaller structure members, typically found in densely spaced metal structures, the uniform pressure model performs well with respect to accurately representing the structure loads. However, for larger members found in modern sandwich structures, the underestimation of structure loads is significant, especially with respect to the shear forces. The non-uniform pressure modeling technique is concluded to be promising regarding its ability to accurately represent the structure loads, regardless of structure member size. The presented methodology is concluded to be a useful tool in further research regarding the evaluation and development of methods for high-speed craft structural design.