Affiliation:
1. Texas A&M University, College Station, Texas 77843
Abstract
This study presents new [Formula: see text] laminar flame speed ([Formula: see text]) data for a wide range of equivalence ratios ([Formula: see text]) at low pressure (0.5 atm) and multiple initial pressures (0.5–3 atm) at an equivalence ratio far from stoichiometry ([Formula: see text]). All experiments were conducted at room temperature using spherically expanding flames. At 0.5 atm, [Formula: see text] peaked slightly lean, reaching a maximum of 411 cm/s near [Formula: see text]. Far from stoichiometry, [Formula: see text] was approximately 72 and 34 cm/s at [Formula: see text] and 2.4, respectively. [Formula: see text] predictions were computed using several commonly cited chemical kinetics mechanisms for methane combustion, with performance approximately the same for all mechanisms. Every mechanism underpredicted [Formula: see text] at 0.5 atm for [Formula: see text], with performance especially poor near stoichiometry ([Formula: see text] underprediction near the peak). For [Formula: see text], experiments were conducted for pressures from 0.5 to 3.0 atm, showing that [Formula: see text] varies approximately according to the power law [Formula: see text]. The mechanisms captured this pressure dependency, with GRI-Mech 3.0 performing especially well. Sensitivity analysis shows that many reaction adjustments are necessary to solve the underprediction near stoichiometry, with [Formula: see text] potentially a reaction of interest.
Publisher
American Institute of Aeronautics and Astronautics (AIAA)