Viscoelastic material similitude for predicting underwater acoustic scattering performances

Area of Science:

• Naval Architecture and Marine Engineering
• Acoustics
• Materials Science

Background:

• Full-scale submarine acoustic scattering experiments are complex and costly.
• Existing acoustic similitude laws struggle with viscoelastic materials crucial for acoustic stealth.
• Frequency-dependent properties of viscoelastic materials distort material similitude.

Purpose of the Study:

• To propose and validate a new similitude concept, viscoelastic material similitude, for accurate scaled modeling of underwater acoustic scattering.
• To address the inaccuracies introduced by viscoelastic materials in current similitude laws.
• To enhance the predictive accuracy of scaled models for submarine acoustic stealth.

Main Methods:

• Establishing the conditions for achieving viscoelastic material similitude.
• Exploring two distinct approaches to satisfy these similitude conditions.
• Validating the proposed approaches using existing experimental data.

Main Results:

• The study demonstrates that viscoelastic material similitude significantly improves predictive accuracy.
• Compared to distorted similitude, the proposed method enhances underwater target strength similitude.
• Validation confirmed the effectiveness of the established conditions and approaches.

Conclusions:

• Viscoelastic material similitude is essential for accurate scaled modeling of acoustic scattering from submarines with stealth coatings.
• The proposed concept overcomes limitations of traditional similitude laws for viscoelastic materials.
• This research offers a practical solution for more reliable and cost-effective laboratory testing of submarine acoustic performance.