Design and Validation of a Reduced Test Matrix for the Autoignition of Gas Turbine Fuel Blends

Changes in fuel composition for both aero-engine as well as power generation applications is a topic of concern since fuel variability can have a great impact on the reliability and performance of the burner design. Autoignition experiments for a wide range of likely fuel blends containing CH4 mixed with combinations of C2H6, C 3H8, C4H10, C5H 12, and H2 are planned in the authors' shock-tube laboratory. However, testing every possible fuel blend and interaction is not feasible within a reasonable time and cost. To predict the surface response over the complete mixture domain, a special experimental design has been developed reducing the amount of 'trials' needed significantly 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 when applied to autoignition at a temperature of 800 K and pressure of 17 atm. A further attempt was made to reduce the 41-test matrix to a 21-test matrix. This was done using special mixture experimental techniques, and the kinetics model was used to compare the smaller matrix to the expected results of the larger one. The new 21-Test matrix produced a numerical correlation that agreed well with the results from the 41-test matrix, indicating that the smaller matrix will provide the same autoignition information as the larger one with acceptable precision. Copyright © 2005 by ASME.

Design and Validation of a Reduced Test Matrix for the Autoignition of Gas Turbine Fuel Blends Conference Paper