Time domain and frequency domain numerical calculation methods for transient noise of cruise ship cabins

Objective The purpose of this paper is to explore an efficient and accurate numerical calculation method for cabin transient noise under transient excitation.

Method First, numerical calculation models of cabin transient noise in the time domain and frequency domain under the vibro-acoustic coupling mode are established respectively. By comparing the numerical calculation results of cabin transient noise under transient acoustic excitation and transient acoustic-force excitation, the differences between the two methods in computational accuracy, efficiency, solution scale, and modeling difficulty are discussed. Considering the broadband characteristics of transient excitation, a full-band numerical calculation method for cabin transient noise under multi-source excitation is given and a real ship test is carried out.

Results The results show that the total level error of cabin transient noise obtained by the test results and recommended numerical method is within 3 dB, which verifies the effectiveness of the numerical method proposed in this paper. The computational accuracy of the time-domain and frequency-domain methods given in this paper are comparable, with the time-domain method showing higher computational efficiency than that of the frequency-domain method, but also higher modeling difficulty. The influence range of transient air noise sources is smaller than that of transient structural vibration sources.

Conclusion The method proposed herein can accurately predict the transient response of large cruise ship cabins and transient noise in the design stage of ship cabins, thereby reducing the design cost.