Executive Summary : | Novel flow blurring (FB) atomizer has been shown to atomize liquids having adverse thermos-physical properties finely. The swirl stabilized burner employing FB atomizer has not been pursued in India for simulated gas turbine applications. However, around the globe, multiple groups have looked into this twin fluid atomizer for simulated gas turbine burner applications or oil-fired burners for process industries. An elongated reaction zone has been the feature of FB atomizer-based combustors due to the high axial velocity of liquid droplets formed in the spray. However, proper attention to primary zone flow-field and vortex breakdown characteristics of swirl stabilized burner have not been given proper attention. The proposed study will look into the improvement in the interaction of swirling combustion air with twin fluid spay developed by FB atomizer, the impact of sudden area expansion ratio, and partial blockage (unchocked) at combustor exit for stabilizing and anchoring the flame. The baseline conditions would be optimized for aviation Jet A1 fuel, and then burner operation on raw vegetable oil and glycerol would be demonstrated. Adverse thermos-physical (viz. viscosity, surface tension) properties of raw vegetable oil and the low calorific value of glycerol, along with its very high viscosity and surface tension, form good candidates to demonstrate fuel flexibility. It may be noted that glycerol is a by-product of the transesterification process to produce biodiesel, and its disposal through utilizing its heat content would complement the renewable fuel production process. The study would employ optical diagnostic techniques such as sLIPI diagnostics, high-speed chemiluminescence, and in-flame species concentration and temperature measurements. Geometric and flow configuration adaptations would be employed to develop a flexible fuel combustor and characterize the operational regime for the three fuels. |