ABSTRACT Spray flame characteristics of canola methyl ester biofuel (CME) and petroleum fuel (No. 2D) are described. An enclosed spray flame in a heated co-flow air environment at ambient pressure was studied. A single nozzle, swirl-type, air-blast atomizer with a nozzle diameter of 300 microns was used to create the spray. The spray droplet size and velocity distributions were measured using a two-component phase Doppler particle analyzer. In-flame temperature profiles were measured using a type-R thermocouple. Global emission indices of NO and CO were derived from concentration measurements in the combustion products. The overall equivalence ratio was kept at 0.75 to simulate lean burning conditions. The changes in atomization air flow rate produced similar changes in atomization characteristics of both fuels. Emission indices of NO and CO for petroleum fuel were higher than those of the CME fuel. In-flame temperature levels were lower for the CME fuel than for the petroleum fuel at corresponding flame locations. NOMENCLATURE CME-Canola methyl ester D 32 -Sauter mean diameter NDIR-Nondispersive infrared PDPA-Phase Doppler particle analyzer T cf = Air co-flow temperature V f = Volumetric flow rate of fuel V aa = Volumetric flow rate of atomization air V cf = Volumetric flow rate of air co-flo
