CFD-Based Analysis of Submarine Drag with Vertical Foreplane Placement Variation

This study investigates the effects of vertical foreplane placement on the drag characteristics of a submarine using Computational Fluid Dynamics (CFD). The analysis was conducted on the Joubert BB2 model with a length of 3.826 m, using the ANSYS CFX package and adhering to the International Towing Tank Conference (ITTC) procedures. Three variations of foreplane placement were developed at 20% of the length from the bow and positioned vertically in the upper, middle, and lower sections of the hull. The model was subjected to a simulation involving complete submersion in water at an inlet velocity of 10 knots. Grid convergence independence and uncertainty analyses were performed to ensure the reliability of the results. The simulation was validated based on previous research, achieving a remarkable accuracy of 2.86%. The results demonstrate that all three alternative models exhibited a reduction in drag compared to the original model, with the lower section placement (Model 3) achieving the most significant decrease (7.36%). The reduction in resistance is attributed to the smoother interaction between the fluid and foreplane in the optimized placement of the foreplane. The fluid flow was symmetrical in the original and middle-section models, whereas the upper and lower section models displayed asymmetrical flow patterns. These findings highlight the importance of precise foreplane placement in optimizing submarine design to enhance hydrodynamic efficiency and reduce drag, ultimately contributing to improved operational capabilities in various underwater environments.