Laminar flame speeds of moist syngas mixtures

Journal Article · Tue Feb 15 04:00:00 EST 2011 · Combustion and Flame

DOI:https://doi.org/10.1016/J.COMBUSTFLAME.2010.09.004· OSTI ID:21401361

Das, Apurba K ^[1]; Kumar, Kamal; Sung, Chih-Jen ^[2]

---

1. Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH 44106 (United States)
2. Department of Mechanical Engineering, University of Connecticut, Storrs, CT 06269 (United States)

This work experimentally investigates the effect of the presence of water vapor on the laminar flame speeds of moist syngas/air mixtures using the counterflow twin-flame configuration. The experimental results presented here are for fuel lean syngas mixtures with molar percentage of hydrogen in the hydrogen and carbon monoxide mixture varying from 5% to 100%, for an unburned mixture temperature of 323 K, and under atmospheric pressure. At a given equivalence ratio, the effect of varying amount of water vapor addition on the measured laminar flame speed is demonstrated. The experimental laminar flame speeds are also compared with computed values using chemical kinetic mechanisms reported in the literature. It is found that laminar flame speed varies non-monotonically with addition of water for the carbon monoxide rich mixtures. It first increases with increasing amount of water addition, reaches a maximum value, and then decreases. An integrated reaction path analysis is further conducted to understand the controlling mechanism responsible for the non-monotonic variation in laminar flame speed due to water addition. On the other hand, for higher values of H{sub 2}/CO ratio the laminar flame speed monotonically decreases with increasing water addition. It is shown that the competition between the chemical and thermal effects of water addition leads to the observed response. Furthermore, reaction rate sensitivity analysis as well as binary diffusion coefficient sensitivity analysis are conducted to identify the possible sources of discrepancy between the experimental and predicted values. The sensitivity results indicate that the reaction rate constant of H{sub 2}+OH = H{sub 2}O+H is worth revisiting and refinement of binary diffusion coefficient data of N{sub 2}-H{sub 2}O, N{sub 2}-H{sub 2}, and H{sub 2}-H{sub 2}O pairs can be considered. (author)

• OSTI ID: 21401361
• Journal Information: Combustion and Flame, Journal Name: Combustion and Flame Journal Issue: 2 Vol. 158; ISSN CBFMAO; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
AIR
ATMOSPHERIC PRESSURE
CARBON MONOXIDE
COMBUSTION KINETICS
COMPETITION
COUNTERFLOW SYSTEMS
DIFFUSION
HYDROGEN
LAMINAR FLAMES
MIXTURES
Moist syngas
SENSITIVITY ANALYSIS
TEMPERATURE RANGE 0273-0400 K
VARIATIONS
VELOCITY
WATER
WATER VAPOR