Non-Intrusive Gas Turbine Combustor Measurement Techniques

The design of can combustors are increasingly relying on computer codes that predict the performance of these systems, thus reducing development costs. However, experimental data are needed to validate the computer models, provide closure to the turbulenceparameters used in the models and provide useful information about the combustor geometry and the flow initial and boundary conditions. Measurements of the instantaneous velocity vector, temperature, and species concentrations are essential to completelyvalidate CFD codes. Our approach is to use diode array velocimetry (DAV) to measure the instantaneous velocity vector, and lamp induced fluorescence to measure the instantaneous temperature/species concentrations. The proposed approach will result in areliable sensor system for obtaining the desired combustor properties (velocity, temperature, and species). The resulting sensor system could be applied in the field for engine health diagnostics.An inexpensive laser velocity/temperature/species instrumentthat does not require laser coherence is in demand for many applications other than the combustion chamber of gas turbines and advanced propulsion systems. Volumetric flow rate measurements is one of the large commercial markets for DAV. Volumetric flowrate measurements are needed for: (1) natural gas custody transfer and/or distribution stations, (2) the flue gases emitted from the smoke stacks, (3) gas turbine engine health diagnostics, (4) air intake for jet airplanes. The inexpensive feature of DAVtechnique will render it the instrument of choice in wind tunnel and laboratory measurements. The incoherence nature of DAV technique will make it a potential candidate for an optical air data sensor for use aboard aircrafts.