CARACTÉRISTIQUES ACOUSTIQUES DU GRAND TUNNEL HYDRODYNAMIQUE DU VAL DE REUIL

Known as GTH (Grand Tunnel Hydrodynamique), France's latest large caviation tunnel intended for naval hydrodynamic and hydroacoustic research, has been in use since 1987. The facility comprises closed and free-surface test sections (CTS and FSTS) in which maximum flox velocities are respectively 20 and 12 m/s. This background noise is function of many parameters such as : velocity, presence of cavitation nuclei, pressure. Experimental results are presented for the 2 test sections. The different values of pressure are : 0.2 - 1 and 3 bars. The value of flow velocities are : 4-6-8-10 m/s for the FSTS and 5-10-20 m/s for the CTS. An other important point considered here is the influence of acoustic confinement. The acoustic response of the test sections are presented in the frequency range : 100 Hz 60kHz. The measurements presented here allow to reconstruct the free field noise radiated by the models.