A surface piercing propeller (SPP) is a propeller that is partially submerged in water and is considered a possible solution to high-speed vessels (greater than 50 knots) where cavitation plays a vital role due to its ever-increasing detrimental effects. Computational Fluid Dynamics (CFD) has become a more prevalent solution in recent years due to lower costs and the ability to evaluate varying setups. However, Computational Fluid Dynamics has had problems accurately solving the hydrodynamic loads for an SPP as recently as a few years ago. Accurately predicting these loads is of great importance because it will allow future simulations to add more effects such as cavitation, shaft inclination effects, multiple propellers, and fluid-structure interaction. Using FINE/Marine, a CFD software specifically designed for marine applications simulations with the 841-B SPP model and changing the Froude number (Fn) and advance coefficient (J), an in-depth validation process and extending upon previous results found when combining CFD and surface-piercing propellers was performed. Several cases between J = 0.6 to J = 1 and Fn = 2 to Fn = 6 are first performed to validate the models against experiments, then more complex features such as multiple propellers and shaft inclination angles were included to extend upon previous work of CFD for surface-piercing propellers. This analysis of the results suggests that CFD models could genuinely be validated against current experimental setups, and therefore more complex additions could also be made and with stronger accuracy than in previous years. / Master of Science / Using computers one can analyze the torque and thrust values of surface-piercing propellers(propeller that is only partially submerged) using commercially available software. This software takes inputs such as the speed of the water and the design of the propeller to evaluate the torque and thrust. A surface-piercing propeller operates in what is known as regimes. There are three of these and they are defined by a number known as the advance coefficient which is defined as the ratio of the boat's speed to the propeller speed. The higher this number the higher the boat speed is and the lower the number is the lower the boat speed. Testing the torque and thrust values accurately has not yet been performed using computers and would be of great value to companies and the government because it lowers the cost and time to create and test different propeller designs for their ships. In this thesis, these tests were performed and done so within a 5% accuracy in all experimental testing on this propeller model. Multiple propellers at once were tested as well as moving the shaft farther out of the water was tested to see how this would affect the overall performance. The results were promising in both of the situations listed, but more testing could be performed as well as adding more features such as cavitation and interaction with the hull.
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/111287 |
| Date | 18 July 2022 |
| Creators | Brookshire, Kaleb |
| Contributors | Aerospace and Ocean Engineering, Coutier-Delgosha, Olivier, Gilbert, Christine Marie, Paterson, Eric G. |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | ETD, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
Page generated in 0.0022 seconds