Abstract
The impact between the wave and the bottom of a high-speed vessel is often simplified as water-entry problems of wedges. Most investigations focus on the water entry of two dimensional (2D) wedges. The effects of added mass and structural damping are still not fully investigated. By combining the normal mode method, the hydrodynamic impact model of rigid wedges and the potential flow theory, a dynamic model for predicting the response of a three dimensional (3D) wedge impacting on water with a constant velocity is established in this paper. The present model can selectively consider the effects of the added mass and the structural damping. The present method has been validated through comparisons with results of published literatures and commercial software. It is found that the added mass can increase the stress response before the flow separation, and reduce the vibration frequency after the flow separation. Due to the effect of the added mass, the stress response of some positions after the flow separation is even higher than that before the flow separation. The structural damping has a negligible effect on the stress before the flow separation, but it can reduce vibration stress after the flow separation.
Highlights
In rough seas, severe impacts usually occur between waves and the bottom of a high-speed vessel, causing impulsive loads on the hull of the vessel
Severe impacts usually occur between waves and the bottom of a high-speed vessel, causing impulsive loads on the hull of the vessel. These hydrodynamic impact loads are characterized by pressures with high peaks and short durations, which may dominate in the design of the hull structure
The structural dynamic equation is established by using the normal mode method
Summary
Severe impacts usually occur between waves and the bottom of a high-speed vessel, causing impulsive loads on the hull of the vessel. These hydrodynamic impact loads are characterized by pressures with high peaks and short durations, which may dominate in the design of the hull structure. As the V-shaped cross-section is a typical section form of the bottoms of high-speed vessels [1], the water entry problem of 2D wedge sections has attracted a great deal of research. Pioneering work can be traced back to von Karman [2] and Wagner [3]. Based on momentum conservation and the concept of added mass, von Karman [2]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have