An investigation of the autoignition of power generation gas turbine fuel blends using a design of experiments approach

Natural gas has grown in popularity as a fuel for power generation gas turbines. However, changes in fuel composition are a topic of concern since fuel variability can have a great impact on the reliability and performance of the burner design. In particular, autoignition of the premixed fuel and air prior to entering the main burner is a potential concern when using exotic fuel blends. To obtain much-needed data in this area, autoignition experiments for a wide range of likely fuel blends containing CH4 mixed with combinations of C2H6, C3H8, C 4H10, C5H12, and H2 were performed in a high-pressure shock tube. However, testing every possible fuel blend combination and interaction was not feasible within a reasonable time and cost. Therefore, to predict the surface response over the complete mixture domain, a special experimental design was developed to significantly reduce the amount of 'trials' needed from 243 to only 41 using the Box-Behnkin factorial design methodology. Kinetics modeling was used to obtain numerical results for this matrix of fuel blends, setting the conditions at a temperature of 800 K and pressure of 17 atm. (Abstract shortened by UMI.)...