Development of a Phosphorescence Technique for Joint Velocity-Scalar-Temperature Measurements in Lean, Premixed, Stratified and Mild Combustion

We aim to develop a diagnostic technique for joint scalar and velocity measurements in lean-premixed, stratified and 'mild' combustion. Such flames require a more detailed understanding of flow, mixing, combustion and their interaction than classical non-premixed flames, and our technique will provide new insights at an affordable cost. Our technique extends the classical PIV by using different types of phosphorescent particles that will allow different fluid streams to be distinguished. The emission decay-rate and the emission spectrum of these particles strongly depend on temperature, which allows the temperature field to be measured at the same time as the velocity field. Eventually, our technique will provide simultaneous velocity/mixing/temperature data, as required for model development and for the design of cleaner, lean premixed gas-turbine combustors, stratified internal combustion engines, and future combustors in the 'mild' combustion regime. A further attractive feature of our technique is its potential to be applied throughout an entire combustor, including the analysis of film cooling near the walls where scattering effects often preclude the use of particle image velocimetry techniques.