Investigation of the effectiveness of a stern foil on a patrol boat by experiment and simulation

Abstract

In the marine industry, specifically fast patrol boats, the important objectives are reducing resistance and improving the efficiency of ships' propulsion systems. The aim of this research was to investigate the application of a stern foil on a patrol boat through experimental and simulation methods. The stern foil used to generate a lift force was an asymmetrical National Advisory Committee for Aeronautics (NACA) foil. In the experiment, the stern foil was installed below the transom of a ship model and positioned parallel to the keel direction (3°towards x-axis). This position created a resultant force, which had an angle to the x-axis. There were variables in this experiment, such as the stern foil application, Froude number (Fr) and hull loads. Those combinations of variables generated sufficient data to analyse the effect of the stern foil working in various conditions. At an optimal load condition (half full load, 2 kg) and Fr 1.1 in the experiment and simulation, the ship model had a resistance reduction of as much as 22.3% and 23.3% in stern foil applications. In addition, with different setups of the stern foil (0°towards the x-axis) in the simulation, a resistance reduction of about 26.7% occurred at Fr 0.9.

Analysis of the Use of Stern Foil on the High Speed Patrol Boat on Full Draft Condition

“…This triggers optimum functioning of the stern foil, raises part of the ship's hull and reduces the overall resistance that exists on the ship models. There is the most optimal condition where stern foil has succeeded in reducing resistance by 24.84 % in Fn 1.2 conditions, this results consistent with the previous results 27,28) . Whereas in the loading conditions of 3 kg (+ 500 gr), it is clear that the conditions of ship model exceed the displacement capacity (3.25 kg) and also the lift force produced by the stern foil (2.8 kg).…”

Lift-to-Drag Ratio of the Application of Hydrofoil With Variation Mounted Position on High-Speed Patrol Vessel

“…This is done so that we get the right amount of mesh for effective computing time and quality results. The design used for the independence test on CFDSOF and experimental data found previous studies using a resistance load cell in the experiment basin where the ship is driven by an external propulsion which will be connected to the data capture device on board [27]. From the above test, it can be concluded that the most appropriate mesh number is ± 350,000 with a computing time of 24 to 25 hours as shown in Table 1.…”

Study on the Resistance Reduction on High-Speed Vessel by Application of Stern Foil Using CFD Simulation

“…Table 2 shows the obtained mesh quality and skewness results. Validation has been carried out by comparing the total resistance from the simulation results with experiments conducted in previous studies [22]. Validation results can be seen in Figure 5.…”