An experimental study of vortex surface interactions and 3-D optical topographic mapping

This document describes the results of an experimental study on vortex surface interactions. The experimental study was performed to help establish a complete understanding of the vortex surface fluid physics necessary to comprehend the surface signature generated by a submerged body. Results showed that higher Froude numbers resulted in stronger surface signatures. The behavior and development of the vortex surface interaction were consistent with observations reported previously. TheAlternate Linearization Method showed that the surface signature is generated by the vortex surface interaction, with the surface pattern not strongly dependent on the surface tension. Preliminary experiments also showed the wave pattern is not strongly dependent on the surface tension.

During the course of the investigation the need for a non-intrusive three- dimensional surface measurement technique was determined. As a result, this study also focused on the design, development, and applications of a new surface measurement and reconstruction technique. The new method was mathematically developed into a unique surface reconstruction technique also useful for other applications, such as machine vision. Preliminary analyses indicate that this new approach has the capability to rapidly map the topography of moving surfaces. This method may be used to determine the topography and velocity of a moving fluid surface. Such information is then useful for better understanding of vortex surface interactions, and as boundary conditions for numerical codes.