Abstract:

With the engine room of certain training ship for navigation teaching being the prototype, the numerical model was developed for three cabins with floating cabin to predict the structure-borne noise (SBN) in ship cabins. The finite element model of multi-tanks structure was built when the vibro-acoustic coupling system was simplified. The predicted results for SBN were compared with the measurements done on a cabin mock-up. The effects of vibration isolator and constraint damping materialss were investigated. Comparisons of the predicted results and the experimental results showed that the developed model could be an effective tool for predicting SBN in ship cabins. The elastic mount installed positions on the auxiliary diesel engine are selected as the force excitation points. The finite element/boundary element method to predict sound pressure level (SPL) of the machinery control room and mechanical workshops of the ship, The sound pressure color nephogram of symmetrical field points on two sides is compared and analyzed, thus the degree of contribution of all bulkheads to the SPL in the right ear position of the duty engineer is acquired. And the floating cabins design based on floating floor is verified to effectively decrease the noise in cabin. The method and process of predicting vibration and sound of the vessel engine room are summarized, which could be a reference for reducing vibration and noise of ships.

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