Figure 20. Classification of different noise reduction methods based on the frequency range of the attenuated noise

From

Investigation of Different Methods of Noise Reduction for Submerged Marine Propellers and Their Classification

Mohammad A. Feizi Chekab, Parviz Ghadimi, Seyed Reza Djeddi, Mehdi Soroushan

American Journal of Mechanical Engineering. 2013, 1(2), 34-42 doi:10.12691/ajme-1-2-3