A Submarine Propeller CFD Using MRF simulation is a computer model of a critical marine propulsion system. Submarine propellers must work underwater where the conditions are very different from air. This Marine Propulsion CFD Analysis helps engineers design better propellers for submarines. The MRF CFD method is a special technique that models rotating propellers without making the simulation too slow or expensive. In Naval Engineering CFD, this approach is essential for studying how propellers create thrust and move submarines forward. The Underwater Propeller Simulation must consider many factors like water flow, pressure changes, and blade forces. Using ANSYS Fluent, engineers can analyze complex flow patterns around the propeller blades. This Thrust CFD analysis is very important for military submarines where performance, efficiency, and quiet operation are critical. The Rotating Machinery Fluent simulation can predict exactly how much thrust the propeller will produce and help optimize the design for maximum efficiency.

Figure 1: A detailed submarine propeller geometry showing the five-blade design used for Marine Propulsion CFD Analysis and Thrust CFD optimization.

Simulation process: Fluent MRF Setup, Multiple Reference Frame Modeling for Rotating Propeller Analysis

To perform this Submarine Propeller CFD Using MRF Fluent study, we first created a detailed 3D propeller model with accurate blade geometry. We used a cylindrical domain to represent the water volume and created a body of influence zone surrounding the propeller blades for mesh refinement. This body of influence approach allows us to concentrate mesh density in the critical flow regions near the blade surfaces where boundary layer effects and pressure gradients are most important for propeller performance prediction.

We used ANSYS Fluent Meshing to generate a high-quality hexa-poly mesh that combines hexahedral cells in the structured regions and polyhedral cells in the complex geometry areas around the propeller blades. The CFD simulation was performed using ANSYS Fluent with the Multiple Reference Frame (MRF) model to simulate rotating machinery without the computational cost of time-dependent calculations. The MRF technique treats the propeller domain as a rotating reference frame while the outer domain remains stationary, enabling steady-state analysis of propeller performance under constant rotational speed. The propeller rotational speed was set to 900 rpm to represent typical submarine operating conditions.

Figure 2: The 3D computational domain and propeller model created for the Submarine Propeller CFD Using MRF Fluent simulation.

Post-processing: CFD Analysis, Thrust Generation and Hydrodynamic Performance Evaluation

The propeller performance analysis from our MRF Fluent simulation demonstrates exceptional thrust generation capabilities. The most significant achievement is the thrust production of 94,600 N, which meets the design requirements for submarine propulsion and validates the effectiveness of our five-blade propeller design. The velocity contours in Figure 3 show smooth flow transition from the undisturbed water regions (cyan areas at 49.76 m/s) to the accelerated flow around the propeller disk (blue-green regions). This smooth velocity transition is critical evidence that the MRF model is working correctly and accurately capturing the physics of the rotating propeller interaction with the stationary water domain.

Figure 3: Velocity contours in the stationary reference frame from the MRF CFD analysis, showing flow patterns and wake formation behind the propeller.

The velocity streamlines in Figure 3 reveal the complex flow physics that generate the propeller thrust. The streamlines display helical flow structures with maximum velocities reaching 65.01 m/s (red regions) at the blade tips where rotational speed is highest. These helical patterns are the signature of efficient propeller operation and confirm that the blades are successfully converting rotational motion into axial thrust. The wake region downstream shows organized vortical structures with velocities ranging from 0 to 32.50 m/s, indicating effective momentum transfer from the rotating blades to the surrounding water.

The wall shear stress distribution in Figure 5 provides crucial engineering insights about blade loading and structural requirements. The stress values range from 0 Pa (blue regions) at stagnation points to 8,705.15 Pa (red areas) at leading edges and blade tips where flow separation and high velocity gradients occur. The symmetric stress patterns on all five blades confirm uniform loading and balanced operation, which is essential for reducing vibration and noise in submarine applications. The maximum shear stress locations correspond directly to the high-thrust regions where the blade geometry most effectively converts rotational motion into forward thrust. The most important achievement of this simulation is its successful prediction of a thrust force of 94,600 N using the MRF method, while simultaneously providing detailed flow analysis that shows uniform blade loading, efficient helical wake formation, and maximum velocities of 65.01 m/s at blade tips, giving engineers complete data for submarine propeller optimization and performance validation.

Figure 4: Velocity streamlines around the submarine propeller from the Rotating Machinery Fluent simulation, revealing complex helical flow structures and tip vortices.

Figure5:  Wall shear stress distribution on the propeller blade surfaces from the Naval Engineering CFD analysis, showing stress patterns and high-load regions.