Sinai J, Waag R C
Department of Electrical Engineering, University of Rochester, New York 14627.
J Acoust Soc Am. 1988 May;83(5):1728-35. doi: 10.1121/1.396505.
A series solution for scattering from two concentric, fluid cylinders of different speeds and densities has been employed to compute the scattered pressure for a range of frequencies, material parameters, and emitter and detector functions. This range includes the nominal parameters of measurements that were made at a frequency of 1.0 MHz and a radius of 150 mm on a gel model with an outer radius of 25.00 mm and an inner radius of 9.52 mm. The nominal parameters correspond to a ka of 626.2 for the measurement radius, a ka of 106.0 for the outer cylinder, and a ka of 39.8 for the inner cylinder. Scattering was calculated for frequencies for 10 kHz to 10 MHz which resulted in ka values from 6.26 to 6262 for the measurement radius, from 1.06 to 1060 for the outer cylinder, and from 0.398 to 398 for the inner cylinder. The effects on scattering of changes in speed and density parameters of the concentric cylinders are presented. First, the speed of the outer cylinder was raised by a factor of 10 from the nominal while the density of the outer cylinder and the speeds and densities of the inner cylinder and the surrounding medium were held fixed. Next, the density of the outer cylinder was raised while its speed was fixed at nominal, as were the speeds and densities of the inner cylinder and the medium. Finally, the speed first and then the density of the inner cylinder was raised while the parameters of the outer cylinder and of the medium were held fixed at nominal.(ABSTRACT TRUNCATED AT 250 WORDS)
已采用一种用于两个不同速度和密度的同心流体圆柱散射的级数解，来计算一系列频率、材料参数以及发射器和探测器函数下的散射压力。该范围包括在频率为1.0兆赫兹、半径为150毫米的凝胶模型上进行测量的标称参数，该凝胶模型的外半径为25.00毫米，内半径为9.52毫米。标称参数对应于测量半径处的波数ka为626.2，外圆柱的ka为106.0，内圆柱的ka为39.8。计算了10千赫兹至10兆赫兹频率下的散射，这导致测量半径处的ka值从6.26到6262，外圆柱的ka值从1.06到1060，内圆柱的ka值从0.398到398。给出了同心圆柱速度和密度参数变化对散射的影响。首先，外圆柱的速度比标称值提高了10倍，而外圆柱的密度以及内圆柱和周围介质的速度和密度保持不变。接下来，外圆柱的密度增加，而其速度固定在标称值，内圆柱和介质的速度和密度也保持不变。最后，内圆柱的速度先增加，然后密度增加，而外圆柱和介质的参数保持在标称值不变。（摘要截于250字）
