摘要: |
The objective of this thesis is to analyze the hydrodynamic properties of a specialized pentahulled, air entrapment, high-speed planning vessel. Due to the unique features of this hull, a multi-layered approach based on computational fluid dynamics was adopted. The first is a steady state model with no free surface effects. It determines the lift and drag on the hull at a fixed waterline. It does not capture any of the planing effects created by the air entrapment region between hulls nor does it quantify, to any degree, the amount of air being ingested into the water jets. The second is a free surface model which includes free surface effects and the generation of the wave train by including the mixed flow regions between hulls. This method also gives an idea of the amount of air that will be present at the water jet inlets. The difficulty with the free surface model is the extremely long computational times required by the program to converge on a solution but if it does generate a solution it will be a much better approximation than the steady state model will produce. Conclusions from the applications of these methods along with recommendations for further research are presented. / NOTE: Master's thesis. / Availability Note: Order this product from NTIS by: phone at 1-800-553-NTIS (U.S. customers); (703)605-6000 (other countries); fax at (703)605-6900; and email at orders@ntis.gov. NTIS is located at 5285 Port Royal Road, Springfield, VA, 22161, USA. |