Ignition delay times, laminar flame speeds, and species time-histories in the H2S/CH4 system at atmospheric pressure Academic Article uri icon

abstract

  • Hydrogen sulfide (H 2 S) composes up to 30% of certain natural-gas resources ("sour gas") and can considerably alter combustion properties of methane (CH 4 ), but few data on H 2 S/CH 4 are available in the literature. In this work, new shock-tube and laminar flame speed data were obtained to facilitate future model validation. For the shock-tube experiments, a fuel-lean (?=?0.5) 30/70 H 2 S/CH 4 blend in 99% argon by volume was shock-heated to temperatures between 1538 and 2144?K and pressures near 1atm. Laser absorption diagnostics at 4.5 and 1.4?μm were employed to measure CO and H 2 O time-histories, respectively. OH∗ chemiluminescence profiles were measured using an emission diagnostic at 307?nm. For the laminar flame speed experiments, measurements were carried out in a constant-volume vessel at 295?K and 1atm for CH 4 /argon and H 2 S/CH 4 /argon (8.25% H 2 S) mixtures from ?=?0.7 to ?=?1.4. The predictions of several recent chemical kinetics mechanisms were compared to the data, leading to the conclusion that species containing both carbon and sulfur are unimportant for shock-tube conditions but can be quite influential for laminar flames. By combining the modeling efforts of two recent works, a tentative new model is proposed that shows marked improvement over the older models in terms of shock-tube ignition delay times. Flame speed predictions show a discrepancy with the new model but follow general experimental trends. To the best of the authors' knowledge, this study provides the first shock-tube data and laminar flame speeds measured in the H 2 S/CH 4 system.

author list (cited authors)

  • Mulvihill, C. R., Keesee, C. L., Sikes, T., Teixeira, R. S., Mathieu, O., & Petersen, E. L.

citation count

  • 11

publication date

  • January 2019