Applications of Statistical Energy Analysis Method to Predict Cabin Noise in a FRP Fastboat

Abstract

To develop a high performance yacht is the target of what the Taiwan Yacht Builders pursue. One of the main requirements of high performance yacht is the ”comfort”. This means low noise and vibration level. Unlike other structure, however, ship structure is much more complex and is affected by external forces from wave impacts, propulsion system (e.g. main engine, propeller), and auxiliary machines, etc. Besides, there is a variety of combination of fiber sheet, resin, and core material in use to form the major hull and cabin structures in FRP boats. Thus, the prediction of shipboard noise in FPR ship is more difficult than in boat with steel or aluminum structures. The goal of this paper is to predict cabin noise level in a FRP fast boat using Statistical Energy Analysis (SEA) method. First, twelve FRP test specimens were built with different lamination scheme according to their locations on the target boat, and vibration tests were performed to obtain the Damping Loss Factors and Coupling Loss Factors for these FRP laminates. These data were then put into the SEA model to predict the cabin noise under different operating conditions. The results show that the predicted noise levels coincide well with the measured data except at fore cabin under transit conditions. And this validates SEA as a potential tool for the noise prediction for FRP boats.