Laminar Flame Characteristics Of Ethanol-Air Mixture:Experimental And Simulation Study

As the most widely used liquid bio-fuel so far, bio-ethanol is attractive for its renewable nature with zero CO2emissions. The development of the second generation bio-ethanol, which are made from non-food-based biomass, would substantially raise the productivity and extend the application of bio-ethanol. For purpose of improving the combustion efficiency and reducing emission, the laminar burning characteristics of fuel ethanol was comprehensively studied through experimental and simulation methods in this paper, the main works and conclusions are listed as follows:1. Using high-speed schlieren photography to record the flame propagation process of ethanol-air mixture with equivalence ratios from0.7-1.7in a spherical explosion bomb, the laminar burning velocities were calculated by both linear and nonlinear extrapolation method All experiments were conducted at initial pressure and temperature of0.1MPa and363K, and a new squeeze method based on the gray gradient of the images was introduced to detect the flame radii accurately. In addition, other laminar burning characteristics including laminar burning flux, flame thickness, Markstein length, Markstein number, activation energy and Ze number were also analyzed under the same conditions.2,Laminar flame speed simulations were performed in flame speed calculation model of Chemkin software with the ethanol oxidation mechanism by Marinov. Results are compared with the experiment data of this paper and from other studies in recent years, as well as the performance of mechanism by Li. In equivalence ratios of1.2and1.4,the experiment results are considerably lower, on average16.3%and22%,than simulation flame speeds of the Marinov mechanism respectively. However, experiment results of equivalence ratios of0.7and1.0are in reasonable agreement with both Marinov and Li mechanism, the mean relative deviations are both lower than3.5%.