CAJ | 학술논문

应用非刚性表面声散射的物理声学方法,发展了基于射线跟踪技术的浅海波导中覆盖消声层目标回声计算的数值方法.选取Benchmark潜艇模型和两种假想的消声覆盖层(反射系数在垂直入射时相同,随角度增加的速率不同),讨论了自由空间和浅海信道中弱正梯度和负梯度两种典型声速剖面条件下刚性及覆盖消声层目标的回声特性.结果指出:由于自由空间和浅海波导中目标回声形成机理不同,这两种覆盖层对自由空间中的消声作用影响较小,对浅海波导中的消声作用影响较大;自由空间中消声覆盖层的消声作用不能完全反映其在浅海波导中的实际效果;在实际浅海波导中为了获得较好的消声作用,不仅要在0度入射角还应在小角度(0-30度左右)范围内将覆盖层的反射系数控制在较小的数值区间.
응용비강성표면성산사적물리성학방법,발전료기우사선근종기술적천해파도중복개소성층목표회성계산적수치방법.선취Benchmark잠정모형화량충가상적소성복개층(반사계수재수직입사시상동,수각도증가적속솔불동),토론료자유공간화천해신도중약정제도화부제도량충전형성속부면조건하강성급복개소성층목표적회성특성.결과지출:유우자유공간화천해파도중목표회성형성궤리불동,저량충복개층대자유공간중적소성작용영향교소,대천해파도중적소성작용영향교대;자유공간중소성복개층적소성작용불능완전반영기재천해파도중적실제효과;재실제천해파도중위료획득교호적소성작용,불부요재0도입사각환응재소각도(0-30도좌우)범위내장복개층적반사계수공제재교소적수치구간.
Applying the physical acoustic method for scattering from nonrigid surface,a numerical procedure based on ray-tracing technique is developed to calculate echoes from targets with anechoic coating submerged in shallow-water waveguide.Taking the Benchmark submarine model and two supposed anechoic coatings with different reflection coefficients (the two coatings have the same value at zero incident angle and different increasing rate with the increase of incident angle),the echo characteristics of target with rigid and coated surface in two typical shallow water environment (weak positive gradient and negative gradient velocity profile) are discussed.The results indicated that the difference of reflection coefficient of the two coatings affects little on anechoic effect in free space but affects more in shallow-water waveguide.It is because that the echo formation mechanisms in free space and in shallow-water waveguide are different.The anechoic effect of coating in free space can not entirely reflect the real anechoic effect in shallow-water waveguide.In order to obtain a larger anechoic effect in shallow-water environment,the reflection coefficient of the coating should be maintained in small value not only at zero incident angle but also in a range of angle from 0 degree to 30 degrees approximately.