Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: small ship

Sortuj według:

Ogranicz wyniki do:

Vibration and radiated noise of a small ship

Gloza I.

Hydroacoustics

2008

Vol. 11

87-96

Extensive measurements "in situ" both of the sound intensity and the vibration were made of M25, a small ship (length 8 m , beam 4 m, displacement 2 tons) powered by 20 kW a direct-drive low-speed diesel engine. A small ship creates a series of harmonics which amplitudes and frequencies are connected with ship speed. The underwater sound measurement was performed for anchored condition. In this paper, two different methods of measurement were used, which provide complementary information. A static method to measure noise from an anchored ship was used when only the main engine was running. In addition to the radiated noise measurements, vibration measurements were conducted aboard this ship. The coherence function was performed to associate each component of underwater noise with the vibrating part of the engine which generates it. The calculation of the sound intensity was made to locate the main source of noise on board. Underwater noise from small ships elevates the natural ambient by 10 - 20 dB in many area; the effects of this noise on the biological environment have been rarely reported.