Proposal for In-Situ Determination of Acoustic Parameters of Navy Coatings for Mold-In-Place Application

摘要

This report documents the research completed on grant N00014-96-0175, In-Situ Determination of Acoustic Parameters of Navy Coatings for Mold In-Place Application, also known as LDV Measurements of Hull Treatment Properties. The objective of this project was to develop a method for in-situ determination of acoustic quality and performance of the mold in-place coatings. The physical parameters which determine the acoustical performance are the complex longitudinal and shear moduli. These properties were determined in-situ by driving the coating with a broadband transient impulse and measuring the surface motion at several points using a laser Doppler probe. In March 2000 the research effort concluded with a set of data points for the test material of interest. This data represents the culmination and integration of several aspects of the work including the recording of ten LDV waveforms, development of an Acoustical Ray Model, half-space definite-integral model, and a complete Hankel-transform model. The data and the models were processed by a Simplex optimization routine to output the desired quantities. The project's achieved level of success shows that this technique could provide a solution to tile in-situ properties determination problem with refinement of some aspects of the technique.