A novel on-line system for measurements of flame steadiness and spectroscopic analysis by integration of multi-branch fibre optics to photonic sensors

This paper describes the design and implementation of a novel instrumentation system using especially fabricated multi-branch fibers coupled to photonic sensors for on-line furnace flame steadiness measurement and spectroscopic analysis. Experimental tests were performed on a lab-scaled multi-burner, multi-fuel combustion rig firing under various air to fuel ratios. Different algorithms using the Goertzel algorithm as well as other weighted statistical relations were used. The results indicate that this new system design exhibits superior performance compared to other systems due to avoidance of beam splitters, luminous spot calibrations and other optical related losses. The flame steadiness was measured at a relative accuracy of ±1.1 % and radical species were identified for gaseous as well as solid fuel firing.