Fluid–Structure Interaction of a Flat-Rudder Floater in N219 Floatplane Maneuvers at the Water's Surface

The N219 floatplane is provided with a rudder for controlling the aircraft's direction during water maneuvers. The existence of the rudder necessitates consideration of its design in order to satisfy quality standards in terms of hydrodynamics and structural integrity. When the rudder is rotated at a particular angle, it exerts a side force and generates a moment that causes the hull of the floater to turn. The difference in fluid pressure on both sides of the rudder is what causes the side force, and fluid pressure further affects the structural integrity of the rudder. This paper describes the interaction between the flow of fluid and the structure of the rudder that occurs during deep aircraft maneuvers. Using computational fluid dynamics techniques based on the N-S equation and the k-ε turbulence model, fluid flow is modeled numerically. The fluid flow analysis is then combined with a transient structural analysis using the finite element method and a two-way coupling system to show how the fluid and structure interact in both directions over time. Each iteration time step displays simulation results in the form of fluid velocity, fluid pressure, structural stress, and structural deformation. The influence of speed and rudder angle on the response of the rudder structure was investigated by simulating nine cases with three different velocities (6, 8, and 10 m/s) and three different rudder angles (15, 25, and 35°). The simulation results indicate that the greatest fluid pressure in 35° is 19.65 kPa, which causes the greatest structural stress of 2398 MPa and a 44% difference in deformation of 15°.