ABSTRACT Proposal Number: CTS-9733388 Principal Investigator: Elliott The Study of Turbulence and Compressible Flows Using Molecular Filter Based Diagnostics The primary goal of this CAREER Award is to support the development of a non-intrusive flow diagnostic technique termed Filtered Angularly Resolved Rayleigh Scattering (FARRS), which will simultaneously measure instantaneous velocity, density, temperature, and pressure. This technique measures the scattering from a point measurement volume from a focused beam of a ND:YAG pulsed laser which interrogates the flow. An anamorphic optical system is used to separately record rays which view the Rayleigh scattered signal at different angles. The image recorded onto an intensified CCD camera results in an intensity verses viewing angle profile. By placing an iodine filter in front of the camera and tuning the laser to an absorption line of iodine, the scattered intensity verses viewing angle profile recorded on the CCD changes shape depending on the velocity, density, temperature, and pressure of the flow. The profile for each instantaneous (10 ns) laser pulse can then be used to compute the fluid properties. Experiments will be made in subsonic and supersonic axisymmetric jets to quantify the accuracy of the measurements, explore improvements to the system to reduce sources of error, and extend the technique to measure multiple points simultaneously. These measurements will be used to verify computational turbulence models of the axisymmetric 'et and improvements will 'II be made to the models when possible. Also during the funding period, improvements will be made to a technique termed Planar Doppler Velocimetry (PDV) which allows the measurement of multiple velocity components in a two dimensional field. Following success of the development of FARRS and PDV, measurements will be made in more complex flows to study compressible turbulence (i.e. boundary layers, and shock boundary layer interactions) and flowfields which are currently being funded at Rutgers by other agencies (a transverse jet in a supersonic cross flow, weakly ionized supersonic flows, and the gas dynamics associated with thermal spray processes). Collaborations have been set up with industry (Innovative Scientific Solutions Inc. and Spectra Physics) and government laboratories (i.e. Wright Laboratory) for this research plan.
