The combustion characteristics of H-2/C3H8/air and CO/C3H8/air premixed flames on a V-shaped burner have been investigated experimentally for future blended fuels with flow visualization, chemiluminescence and analysis of exhaust gases. The lean flammability of H-2/C3H8/air is expanded to 0.38 and that of CO/C3H8/air is expanded to 0.50 on the V-shaped burner. The flame configurations, flow structures, distributions of chemiluminescence intensity of CH* and OH*, flame temperatures and CO emissions under varied mixture conditions were recorded during the combustion. Two flame configurations were observed - of types M and hill. The addition of H-2 and CO to the fuel altered the flame pattern from hill-type to M-type (shorter flame) because the burning velocity, temperature and flame intensity increased with the addition of H-2 and CO in the fuel. Analysis of flow visualization and chemiluminescence revealed the impinging effect, in which the collision of mixture jets decreases the main flow velocity and increases the residence time. It results in a greatly decreased leakage of the unburned mixture with accumulated heat acting as a well stirred combustible mixture for improved flame stabilization. At phi = 0.6, the flame temperature of H-2/C3H8/air with M-type flame is 1.37 times that of CO/C3H8/air with hill-type flame, while the C3H8/air flame is extinguished. The combustion of CO that occurs in the impinging region resulted in decreased CO emissions when the addition of CO to the fuel surpassed 73.7%. These findings about the combustion characteristics, mechanisms and effects of fuel variability provide industries with an effective concept of burning blended fuels, and are applicable to syngas combustion. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.