عنوان مقاله [English]
Submarines can be identified in several ways, which acoustic noise is one of the most important of them. In submarines, the highest score is acoustic stealth. Acoustic noise emission is very important in detecting the position of the submarine; Because it can be emissioned at high speed and over long distances according to the nature of the sea environment and can be detected and classified. Considering the impact that submarines had on World Wars I and II as a result of the war and the importance of their presence in naval wars, reducing acoustic noise, in addition to hiding the submarine from the enemy, makes submarine sonar systems more efficient (in detecting operation). Sources of noise production in submarines are divided into three categories: hull noise, internal machinery and equipment, and propulsion system, especially submarine propeller noise. In this research while studying on the source of noise production in submarine, the active and inactive methods for reducing the submarine acoustic noise has been investigated. The first step in eliminating or reducing noise and controlling it, is to know the mechanisms of noise production and emission, so that subsurface operations can be performed in complete secrecy. In order to reduce noise, we can use the first effective methods that are applied directly to the source of noise as well as the secondary method (active and inactive) that is applied to the emission path and the submarine hull. This research is an applied, descriptive method with a mixed approach that collecting real and detailed information, the researcher has expressed the methods of reducing acoustic noise in subsurface operations. In this study, the value of the statistical population is limited and specified to the subsurface flotilla of the first naval district in Strategic Navy of the Army of the Islamic Republic of Iran (I.R.I.N). Therefore, the sample size corresponds to the size of the statistical population of 86 people. Finally, after collecting the data, the researcher performed Cronbach's alpha tests and T-test to investigate the relationships between variab les with noise reduction.