Throughout the history of naval architecture the idea of reducing frictional resistance has been the focus of extensive theoretical and experimental research. One potential method for reducing drag is the use of air on the underside of a vessel in the form of Bubble-Induced-Skin-Friction-Drag-Reduction (BDR) and Air-Layer-Drag- Reduction (ALDR). The latter, ALDR, is the focus of this thesis. This document covers flat-plate experimental research conducted using the Webb Institute Flow Channel during the spring of 2012. The objectives of this project were to demonstrate drag reduction at a variety of conditions, including varying speeds, air injection rates, and deadrise angles. A secondary objective was to map the distribution of air migration on the underside of the surface as a function of these conditions. During experimentation conclusive evidence was gathered to support the validity of the ALDR concept, although scaling has not been addressed. Some recommendations for continued work include exploring this concept in experimentation of air entrapment hull forms or analysis of performance characteristics at full scale.
Experimental Study of Air Layer Drag Reduction with Bottom Cavity for A Bulk Carrier Ship Model