Abstract
A high-power laser is used to produce via thermal expansion a long thermoacoustic broadside array in water by deflecting a ruby-laser beam (optical wavelength 0.6943 μm) off a rotating mirror to a body of water. The rotation of the mirror results in a rectilinear motion of the source over the water surface. Such a source is commonly referred to as a moving thermoacoustic array (MTA) and its penetration depth into the water is inversely proportional to the coefficient of absorption of the laser intensity in water. The sound field radiated by the ruby MTA (long array) is analyzed experimentally for subsonic, sonic, and supersonic source velocities. The results obtained with the long ruby MTA are compared with those obtained with a much shorter glass–neodymium MTA (optical wavelength 1.06 μm). Results reported here include directivity patterns, both in a plane perpendicular to the water surface and in a plane parallel to the water surface, and sound-pressure level (SPL) dependence on distance between the source and the receiver.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call