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[Objectives] To study the coating effects on structures subjected to near-field underwater explosion, [Methods] the coupling Runge-Kutta Discontinuous Galerkin Method, Boundary Element Method and Finite Element Method are developed in this paper to solve a rubber coating circular plate subjected to near-field underwater explosion. The results are compared with experimentally obtained wet face pressure and bubble shape to verify the method, and the explosion bubble response to the flexible boundary is discussed. [Results] The results indicate that the rubber coating plate will shorten the pulse width of the shockwave, but the cavitation collapse will occur more easily. In addition, solid rubber coating has little effect on the deformation of the explosion bubble. [Conclusions] This research can provide a theoretical basis and technical support for the coating design and optimization of warships subjected to near-field underwater explosion.

[Objectives] To improve the shock resistance ability of submarines, [Methods] an anti-shock cladding for submarines which consists of a compound coating with rubber and plastic foam is proposed on the basis of the shock environment of submarines. The numerical model is established by Abaqus/Explicit to analyze the dynamic response of anti-shock cladding under the combined loads of hydrostatic pressure and underwater explosion loads. [Results] The results indicate that the deformation of the cladding is negligible under hydrostatic pressure, and the shock load is largely mitigated when the yield stress of the cladding is higher than the hydrostatic pressure. Conversely, the deformation of the cladding is great under hydrostatic pressure and the shock mitigation effects of the coating are weakened when the yield stress of the cladding is lower than the hydrostatic pressure. As such, the yield stress of the cladding should be higher than the hydrostatic pressure, and densification should be avoided. [Conclusions] The research findings in this paper can provide guidance for the design of anti-shock cladding for submarines.

Harmonic axial force resulting from a propeller’s first vibration mode is a major cause of tonal sound radiation of an underwater vehicle. To reduce the harmonic force, we employ a dynamic antiresonant vibration isolator (DAVI) in parallel with thrust bearing of the shafting system to attenuate vibration transmitted to the hull. The methods of transfer matrices and substructure synthesis are used to create a semi-analytical dynamic model of the propeller–shaft–hull system with DAVI. In this model, the elastic properties of the propeller and foundation are taken into consideration. The force transmissibility and power flow are then used to evaluate the isolation performance of the DAVI. For the purpose of comparison, a resonance changer (RC) proposed in the published literature is also used to reduce the axial vibration transmission. It is demonstrated numerically that by using DAVI, the vibration and power flow of the underwater vehicle are greatly attenuated at the designed frequency without obviously changing the axial fundamental resonance frequency of the shafting system, which is superior to the RC isolator. [ABSTRACT FROM AUTHOR]