This Small Business Innovation Research Phase 1 project establishes the feasibility of a novel statistical absorption tomography technique to retrieve the statistics of local properties at very high spatial resolution from path integrated measurements made in turbulent flows.  Tomographic techniques are widely used in the medical field, but are restricted to time-invariant phenomena, such as laminar flows or stationary objects.  The two distinguishing features of the current high resolution statistical tomography demonstrated during the Phase I research effort are: (1) a statistical deconvolution technique to obtain the Probability Density Functions (PDFs) of specific absorption coefficient with high spatial and temporal resolution, and (2) a laser sheet/diode array system to obtain the high resolution measurements required for the statistical tomographic technique. 

Local PDFs of specific absorption coefficients are required for non-intrusive monitoring of the particulate and gas species concentrations in a wide variety of turbulent flows.  Specific applications include pollution control in smoke stacks, process control in power plants, stability control in gas turbine engine premixers, and manufacturing control in metal and ceramic powder processing.  The proposed technology is designed to provide a new process monitoring tool for particulate and gas species concentrations in industrial flows and has immediate commercial utility in the power plant, powder processing and gas turbine industries.

During the Phase I research, the experimental optical system was designed and fabricated.  Spatially resolved path integrated transmittances were successfully obtained.  The statistical deconvolution in conjunction with the experimental hardware was successful in providing the statistics of local transmittances with a spatial resolution of 0.4 mm.  This is the first time that the statistics of local transmittances have been measured with such high spatial resolution.  This is crucial for the research community since the data obtained can be used to critically evaluate turbulence mixing models.  If similar measurements are obtained in a sooting flame, the results can also be used to evaluate soot kinetics models.  This is a significant achievement for the Phase I feasibility study.  The feasibility of the technique has been conclusively proven during the Phase I work. During Phase II, the prototype systems will be built for commercialization