海洋環境騒音の垂直方向性に対する風力場の異質性の影響に関する機械的洞察
Xiaoming Cui1,2, Qing Hu1
1School of Ocean Engineering and Technology, Sun Yat-sen University, Zhuhai 519000, China.
The Journal of the Acoustical Society of America
|September 5, 2025
まとめ
風力場特性は,浅い水域での水中環境騒音の方向性を大幅に制御します. 空間的変動と風の傾きは周波数間の音響エネルギーの分布に影響を与え,より高い解像度のモニタリングを必要とする.
科学分野:
- 海の音響
- 環境流体力学
- シグナル処理
背景:
- 浅い水域の垂直方向性は,風力場によって影響を受けます.
- 従来のモデルはしばしば近地源と均一な風の条件を想定します.
研究 の 目的:
- 浅瀬での周囲の騒音の垂直方向性に関する風力場制御メカニズムを明らかにする定量的な枠組みを確立する.
- 風による騒音分布の空間的および周波数に依存する特性を調査する.
主な方法:
- 南シナ海の北部の垂直線配列からのフィールド観測を利用した.
- 通常モード理論,音速プロファイル,海底特性,多源風場 (ERA5再分析/合成データ) を採用した.
- 音響データを分析し,ノイズエネルギーの値,周波数依存分布,モデルの検証を決定した.
主要な成果:
- 20kmの空間的なノイズエネルギーの値が特定され,従来の近地仮定を超えています.
- 観測された周波数依存の騒音分布:近地源に関連した低周波の騒音,海に向かって高周波のエネルギーシフト.
- 変動する風の傾斜の下での均等な風近似から量化された誤差は,強い傾斜で重要な偏差を強調します.
- 強い風のグラデーション-周波数カップリングが 牧草角度バイアスを影響しています.
結論:
- 風の異質性を考慮する必要性を強調し,古典的な均質風の騒音モデルを改訂しました.
- 5kmの空間解像度で 精密な海洋音響モニタリングを義務付けました
- 3Dプロパガンダとバブルダイナミクスの将来的な統合を提案し,予測能力を向上させる.
関連する概念動画
Influence of Earth's Curvature and Atmospheric Refraction on Leveling
266
During leveling, the Earth's curvature and atmospheric refraction introduce deviations in the line of sight from a true horizontal reference. When the line of sight is leveled, it remains perpendicular to the plumb line only at a single point. Beyond this, it deviates due to the Earth’s curvature, represented by the correction C. For a sight distance D, the deviation can be derived using the relationship:This relationship shows that the deviation increases quadratically with distance.
266
Boundary Layer Characteristics
215
When a fluid encounters a solid surface, a boundary layer forms due to the interaction between the fluid's motion and the stationary surface. This phenomenon is characterized by a thin region adjacent to the surface where viscous forces dominate, influencing the fluid's velocity profile. The development of the boundary layer begins at the leading edge of the surface and evolves as the fluid moves downstream.As the fluid flows over the surface, friction between the fluid and the wall slows down...
215
Magnetostatic Boundary Conditions
1.1K
An electric field suffers a discontinuity at a surface charge. Similarly, a magnetic field is discontinuous at a surface current. The perpendicular component of a magnetic field is continuous across the interface of two magnetic mediums. In contrast, its parallel component, perpendicular to the current, is discontinuous by the amount equal to the product of the vacuum permeability and the surface current. Like the scalar potential in electrostatics, the vector potential is also continuous...
1.1K
Sound Waves: Interference
3.9K
Sound waves can be modeled either as longitudinal waves, wherein the molecules of the medium oscillate around an equilibrium position, or as pressure waves. When two identical waves from the same source superimpose on each other, the combination of two crests or two troughs results in amplitude reinforcement known as constructive interference. If two identical waves, that are initially in phase, become out of phase because of different path lengths, the combination of crests with troughs...
3.9K
General External Flow Characteristics
269
The study of external flow is essential for creating structures and objects that interact efficiently and safely with moving fluids, such as air or water. When a body is immersed in a flowing fluid, it experiences two primary forces: drag, which opposes motion along the flow direction, and lift, which acts perpendicular to the flow. The shape, size, and orientation of the object influence these forces.Streamlined and Blunt Bodies in External FlowObjects in fluid flow are classified as...
269
Intensity and Pressure of Sound Waves
1.2K
The intensity of sound waves can be related to displacement and pressure amplitudes by using their wave expressions and the definition of intensity. The critical step to achieve this is to write the power delivered by the particles on the wave as the product of force and velocity and simplify the force per unit area as the pressure. The velocity of the medium's particles can be derived from the displacement.
Unlike the time average of a sinusoidal term, which is zero since it is positive...
Unlike the time average of a sinusoidal term, which is zero since it is positive...
1.2K


