US 11,237,258 B1 · Method for optimization of a parametric array shallow profile difference frequency conversion performance

Abstract

A method for optimization of a parametric array shallow profile difference frequency conversion performance, comprising the following steps: building a three-layer parametric array shallow profile emission acoustic wave propagation path model, and establishing a detection horizontal position DL equation capable of detecting a detection performance of the parametric array shallow profile; and building a model for optimization of the parametric array shallow profile difference frequency conversion performance. A parametric receiving array includes the receiving hydrophone and a pump transducer, comprising: a silicone rubber column is added between the receiving hydrophone and the pump transducer to improve the conversion efficiency of the parametric receiving array. The present disclosure improves the conversion efficiency of the parametric receiving array by increasing the high-frequency power and acoustic pressure level and reducing the ratio to improve the conversion efficiency and the parameter receiving array uses silicone rubber columns.

A method for optimization of a parametric array shallow profile difference frequency conversion performance, comprising the following steps:

S1:
building a three-layer parametric array shallow profile emission acoustic wave propagation path model, the three-layer parametric array shallow profile emission acoustic wave propagation path model includes a water layer, a sedimentary layer and a rock layer;
the sedimentary layer is a pore fluid formed by particles, and establishing a detection horizontal position DL equation capable of detecting a detection performance of the parametric array shallow profile and estimating an echo level at a ground profile and a top of a rock formation:
DL=SL−(PG+DLW·S+ALW)−TLW·S−ALS−RLS·R−TLS·W+RVS+RG+SPG:
the SL is a horizontal position of an acoustic wave emission source, the PG is a generation efficiency from an initial wave frequency to a difference frequency, the DLW·S is a diffusion loss of an initial wave in a water and the sedimentary layer, and the ALW is an absorption loss of the initial wave in a water, and a unidirectional wave propagation between a transducer and a surface of a sediment is regarded as a nonlinearity and a wave propagation of the transducer reflected from the surface of the sediment is regarded as a linearity;
the TLW·S is a transmission loss of the initial wave at a boundary between the water layer and the sedimentary layer and the TLS·W is the transmission loss of an echo at the boundary between the water layer and the sedimentary layer;
the ALS is the absorption loss of the initial wave in the sediment;
the RLS·R is a reflection loss at the boundary between the sediment and the rock layer;
the RVS is a voltage sensitivity of a receiving hydrophone for an acoustic echo;
the RG is a gain of the receiving hydrophone;
and the SPG is a signal processing gain of the receiving hydrophone;
S2:
building a model for optimization of the parametric array shallow profile difference frequency conversion performance and calculating a low-frequency wave radiation power Wed:
W
ed
=
ρ
f
⁢
e
α
S
⁢
r
2
⁢
ρ
S
⁢
c
S
⁢
4
⁢
π
⁢
⁢
r
;
=
w
4
⁢
β
2
⁢
w
1
⁢
w
2
2
⁢
πρ
S
⁢
c
s
7
⁢
γ
;
a propagation distance of an acoustic wave in the water is r, the propagation distance in the sediment is d;
and a propagation speed of the acoustic wave in the water is cR, the propagation speed of the acoustic wave in the sediment is cS, and the propagation speed of the acoustic wave in a rock is cW;
a water density is ρW, a sediment density is ρS, and a rock density is ρR;
an attenuation coefficient of the acoustic wave absorbed in the sediment is αS;
the β is a porosity of the sediment, the e is an expansion rate of a member attached to the model for optimization of the parametric array shallow profile difference frequency conversion performance, and the γ is a structure factor of a transmitted acoustic wave propagation path model;
wherein, the w1 and the w2 are frequencies of two high-frequency frequencies respectively, since the frequencies of the two high-frequency frequencies are similar,
W
1
=
W
2
=
W
2
and the w is a total radiated wave frequency;
the ρf is a pore fluid density in the sediment, and ρs=βρf+(1−β)ρg and the ρg is a particulate matter density in the sediment;
S3:
calculating a low-frequency wave conversion efficiency, and the low-frequency wave conversion efficiency is a ratio of a low-frequency wave frequency Wed to a total radiated wave frequency W:
W
ed
W
=
2
⁢
π
3
⁢
β
2
⁢
f
d
4
⁢
W
/
ρ
S
⁢
c
s
7
⁢
γ
2
;
the fd is a differential frequency;
S4:
adjusting and increasing a high-frequency power and a high-frequency acoustic pressure level and reducing the ratio
W
e
⁢
d
W
=
2
⁢
π
3
⁢
β
2
⁢
f
d
4
⁢
W
/
ρ
S
⁢
c
s
7
⁢
γ
2
to improve a conversion efficiency.
W
e
⁢
d
W
.

144 more elements

Method for optimization of a parametric array shallow profile difference frequency conversion performance

Life of this patent

Method for optimization of a parametric array shallow profile difference frequency conversion performance

Life of this patent

Abstract

Claims7