Transient Hydrodynamic Characteristics Of Gliding-hydrofoil Craft And Hull Design

Recently,the research on high-speed craft will continue to be a challenge in ship design.The focus on the development of high-speed craft is how to increase the speed and how to make the navigation performance better.A Gliding-Hydrofoil Craft(GHC)is similar to a planing hull but with a hydrofoil in the front part of its body.The fixed hydrofoil improves the seakeeping properties and stability of the craft compared with a conventional planing hull.In addition,the GHC has a more simple structure and higher stability when compared to a hydrofoil craft.The main research work and analysis can be summarized as follows:(1)According to the relevant literature,referring to the parent ship'main dimension,using Maxsurf software to design the three types of GHC: M type,H type and swallowtail type,and then imported to the CATIA software,added a hydrofoil on the hull bow and the establishment of three-dimensional model.(2)Choosing a 11.8m planning hull as the parent ship according to the scale of 1:10zoom,using the commercial CFD software FINE/Marine to simulate the hydrodynamic characteristic of planning craft with different speed.Through comparing the simulation results and experimental data to verify the accuracy of the commercial software FINE/Marine.(3)Numerical simulation of transient hydrodynamic characteristics and motion response of GHC by using FINE/Marine software.The M type,H type and swalllowtail type of GHC,speed were 8m/s,10m/s and 12m/s,calculated under 9 conditions.Analysised heave change,pitch change,transient flow field change and the bottom surface of the transient flow field pressure distribution of different hull.The lift,resistance and drag ratio,static displacement and lift ratio of different boats under different speeds were analyzed.The ratio of resistance to static displacement at different speeds was analyzed.Obtain: The navigation state of M-GHC at 10m/s is better than 8m/s and 12m/s;The navigation state of H-GHC at 12m/s is better than 8m/s and 10m/s;The navigation state of swallowtail-GHC at12m/s is better than 8m/s and 10m/s.(4)Three kinds of GHC at the same speed of attack waves numerical simulation,through different boat types of GHC in waves under the condition of the vertical velocity change,the simulation results of weight change,or pitching angular velocity,longitudinal angle changes,combined with the comparison of different types of boat lift and drag,the Htype of GHC,the hydrofoil craft in the seakeeping is better than M and swallowtail type.