Hydro-resistance and Running Stability Investigation for Twin Floats Seaplane

Abstract

Twin floats seaplane requires good resistance and planning stability performance for safe operations in rough water. The hydro-resistance and running stability of floats varies significantly depending on their float hull forms, the coupling influence of aerodynamic and hydrodynamic. Four float hulls that have almost the same displacement and principal dimension are designed and the hydrodynamic characteristics including water resistance and stability limits of those hulls are estimated by high-speed model tests, in which only single float model is used and aero-lift and moment are simulated, this model test method is sufficient to gain characteristics and stability limits and convenient to conduct especially during the float design process. As to the CFD computation of planning problem, a kind of method which is divided into two phase is brought out, in the first phase water viscidity is ignored so we get a relatively exact computation results of trim and heave, this results are treat as the initial status for the second phase so mesh grid distortion or stretch could be avoided, result in computation efficiency and accuracy increase. As compared to the test results, the error of hydro-resistance and trim are within 20% and 15% respectively.