Multiple scattering correction to measurement of beam attenuation in bubble wakes

LU Gang; SUN Chun-sheng; ZHANG Xiao-hui

doi:10.3969/j.issn.1001-806.2012.04.014

For analyzing the influence of multiple scattering on measuring beam attenuation in bubble wakes,the correction coefficient was introduced which denotes the extent of multiple scattering,and its theoretical formulations was derived by means of a narrow angle approximation solution to the radiation transfer equation.Given a typical bubbles size distribution function and number density in bubbles wakes,the relation among the correction coefficient and detector field of view(FOV),wake optical depth,beam size,received section size were analyzed by numerical calculation.Analysis shows that the influence of FOV in forward small angle on the correction coefficient is great,but it has a little change when the FOV is wide;and the impact of optical depth on the correction coefficient is prominent,besides the impact is more prominent when the optical depth is less than 1;and the effect of received section size on the correction coefficient is very little when depth is less than 1,but it becomes visible as the optical depth increase;the influence of beam size on the correction coefficient is comparatively less,further the correction coefficient almost keeps changeless when the beam size is large.The research proposes a theoretical foundation for choice and optimization of conditions during measuring beam attenuation in bubble wakes.

Multiple scattering correction to measurement of beam attenuation in bubble wakes

Corresponding author: ZHANG Xiao-hui, zhangxiaohui505@vip.sina.com

1. School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China;

2. Department of Weaponry Engineering, Naval University of Engineering, Wuhan 430033, China

Received Date: 2011-11-17

Accepted Date: 2011-12-29

Available Online: 2012-07-25

Abstract: For analyzing the influence of multiple scattering on measuring beam attenuation in bubble wakes,the correction coefficient was introduced which denotes the extent of multiple scattering,and its theoretical formulations was derived by means of a narrow angle approximation solution to the radiation transfer equation.Given a typical bubbles size distribution function and number density in bubbles wakes,the relation among the correction coefficient and detector field of view(FOV),wake optical depth,beam size,received section size were analyzed by numerical calculation.Analysis shows that the influence of FOV in forward small angle on the correction coefficient is great,but it has a little change when the FOV is wide;and the impact of optical depth on the correction coefficient is prominent,besides the impact is more prominent when the optical depth is less than 1;and the effect of received section size on the correction coefficient is very little when depth is less than 1,but it becomes visible as the optical depth increase;the influence of beam size on the correction coefficient is comparatively less,further the correction coefficient almost keeps changeless when the beam size is large.The research proposes a theoretical foundation for choice and optimization of conditions during measuring beam attenuation in bubble wakes.

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Reference (15)

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Multiple scattering correction to measurement of beam attenuation in bubble wakes

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