A new criterion was proposed to divide the frequency range of cabin noise prediction within full frequency. The vibro-acoustic models of oil tanker for cabin noise prediction in low frequency, middle frequency and high frequency were established. The full frequency cabin noise prediction was achieved by using the Finite Element Method (FEM), the Finite Element and Statistical Energy Analysis hybrid method (FE-SEA) and the statistical energy analysis (SEA) respectively. The results were compared with the measured values, which shows that the error between the simulation value and the measured value is within 4 dB(A). The prediction results of cabin noise are accurate and reliable. The acoustical optimization design of sound absorbing material was realized by using different optimization algorithms. The optimization results show that the combination of genetic algorithm (GA) and sequential quadratic programming (SQP) can be used to get better sound package and also to reduce the optimization time.
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