Research On Absorption Coefficient Measurement Technology Of Marine Environment Simulation Pool

The cepstrum analysis method which measures the absorption coefficient of the marine environment simulation pool was studied in this paper. The absorption coefficient is an important performance parameter of the marine environment simulation pool, the marine environment simulation pool is an important essential facility to china’s military, scientific research fields, and it has a great significance for china’s national defense and economic development. Cepstrum analysis has been amply analyzed in this paper. Base on the analysis results, simulation project has been designed. The various circs that may appear in actual measurements has been simulated in the simulation project. Base on the various characteristics of the cepstrum analysis the actual layout scheme has been instituted.Some limitations of cepstrum analysis method to measure sound absorption coefficient are found in the data processing phase. For example, the problem of a high signal to noise ratio is encountered in the real measuring phase. Cepstrum analysis requires highly on the signal-to-noise ratio, excessive noise would cause the data processing problems. Base on the existing conditions of noise, better results can be achieved by using the direct measurement. So this problem has been solved by this way that the direct wave signal and reflected wave signals are measured separately. The direct method can calculate the absorption coefficient of sound-absorbing material by using the definition of the reflection coefficient. Base on analysis result, the direct method is an effective method of measuring the absorption coefficient of sound-absorbing material. The direct method has a strong adaptability, lower requirement of measurement environments. By using the direct method, the absorption coefficient can easily be measured in the laying site of sound-absorbing material, and the accuracy of measurement data is greatly improved.In addition, the spherical method measurement of the absorption coefficient of sound-absorbing material is briefly analyzed in this paper.Firstly the measurement principle is deduced, and base on the measurement principle, the measuring arrangement drawing is designed. And by using the previous measurement data makes approximate calculation. The results show that the method has a great maneuverability. The sound pressure of the other points can be calculated by measuring the sound pressure at any point on the sound path, and then calculates the absorption coefficient of sound-absorbing material. This method can be used as one of the common measurement methods of sound absorption coefficient.