摘要Nonlinear effect on focusing gain of acoustic field radiated from a 1-MHz focusing transmitter with a wide aperture angle of 35° is theoretically and experimentally investigated. With the enhancement of nonlinearity, the focusing gains of both intensity and peak positive pressure show non-monotonic behaviour. There exist the same saturated levels at which the maximum outputs are reached and their spatial distributions are more localized. In contrast, the peak negative pressure always decreases monotonically and its spatial distribution is less localized.
Abstract：Nonlinear effect on focusing gain of acoustic field radiated from a 1-MHz focusing transmitter with a wide aperture angle of 35° is theoretically and experimentally investigated. With the enhancement of nonlinearity, the focusing gains of both intensity and peak positive pressure show non-monotonic behaviour. There exist the same saturated levels at which the maximum outputs are reached and their spatial distributions are more localized. In contrast, the peak negative pressure always decreases monotonically and its spatial distribution is less localized.
LIU Ming-He;ZHANG Dong;GONG Xiu-Fen. Nonlinear Effect on Focusing Gain of a Focusing Transducer with a Wide Aperture Angle[J]. 中国物理快报, 2007, 24(8): 2267-2271.
LIU Ming-He, ZHANG Dong, GONG Xiu-Fen. Nonlinear Effect on Focusing Gain of a Focusing Transducer with a Wide Aperture Angle. Chin. Phys. Lett., 2007, 24(8): 2267-2271.
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