Fluid–structure interaction and impact resistance of dual-liner water-lubricated bearings under transient loads

The impact resistance of water-lubricated bearings (WLBs) is a critical factor in ensuring the structural stability of the ship propulsion system and extending its service life. This study develops a fluid–structure interaction model that couples structural elasticity with incompressible fluid dynamics for dual-liner WLBs. An impact waveform function is constructed based on the BV043/85 standard, and numerical analysis is performed to investigate the dynamic response characteristics of the bearings under transient impact loading. The effects of eccentricity, rotational speed, and liner material properties on the bearing's impact resistance are analyzed and compared. The pressure distribution within the bearing's water film, liner deformation, and changes in Von Mises stress under different operating conditions are systematically studied. The results show that the shock wave characteristics are significantly correlated with the bearing's response. Under the same impact conditions, as eccentricity increases, the maximum deformation and maximum stress of the bearing liners increase by 31.6% and 95%, respectively. Similarly, as rotational speed increases, the maximum deformation and maximum stress increase by 45.7% and 52.7%, respectively. The elastic modulus of the liner material also plays a critical role. Materials with a low modulus exhibit larger deformation but lower peak stress due to weaker stress concentration effects. This research provides theoretical guidance for the design and optimization of high-reliability WLBs under impact conditions.