0
Research Papers: Gas Turbines: Combustion, Fuels, and Emissions

High-Speed Imaging and Measurements of Ignition Delay Times in Oxy-Syngas Mixtures With High CO2 Dilution in a Shock Tube

[+] Author and Article Information
Samuel Barak

Center for Advanced Turbomachinery and
Energy Research (CATER),
University of Central Florida,
Orlando, FL 32816
e-mail: sambarak@Knights.ucf.edu

Owen Pryor

Center for Advanced Turbomachinery and
Energy Research (CATER),
University of Central Florida,
Orlando, FL 32816
e-mail: owenpryor@knights.ucf.edu

Joseph Lopez

Center for Advanced Turbomachinery and
Energy Research (CATER),
University of Central Florida,
Orlando, FL 32816
e-mail: jlopez12@knights.ucf.edu

Erik Ninnemann

Center for Advanced Turbomachinery and
Energy Research (CATER),
University of Central Florida,
Orlando, FL 32816
e-mail: erik.ninnemann@knights.ucf.edu

Subith Vasu

Center for Advanced Turbomachinery and
Energy Research (CATER),
University of Central Florida,
Orlando, FL 32816
e-mail: subith@ucf.edu

Batikan Koroglu

Lawrence Livermore National Lab,
Livermore, CA 94550
e-mail: koroglu1@llnl.gov

Contributed by the Combustion and Fuels Committee of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received June 9, 2017; final manuscript received June 18, 2017; published online August 23, 2017. Editor: David Wisler.

J. Eng. Gas Turbines Power 139(12), 121503 (Aug 23, 2017) (7 pages) Paper No: GTP-17-1209; doi: 10.1115/1.4037458 History: Received June 09, 2017; Revised June 18, 2017

In this study, syngas combustion was investigated behind reflected shock waves in order to gain insight into the behavior of ignition delay times and effects of the CO2 dilution. Pressure and light emissions time-histories measurements were taken at a 2 cm axial location away from the end wall. High-speed visualization of the experiments from the end wall was also conducted. Oxy-syngas mixtures that were tested in the shock tube were diluted with CO2 fractions ranging from 60% to 85% by volume. A 10% fuel concentration was consistently used throughout the experiments. This study looked at the effects of changing the equivalence ratios (ϕ), between 0.33, 0.5, and 1.0 as well as changing the fuel ratio (θ), hydrogen to carbon monoxide, from 0.25, 1.0, and 4.0. The study was performed at 1.61–1.77 atm and a temperature range of 1006–1162 K. The high-speed imaging was performed through a quartz end wall with a Phantom V710 camera operated at 67,065 frames per second. From the experiments, when increasing the equivalence ratio, it resulted in a longer ignition delay time. In addition, when increasing the fuel ratio, a lower ignition delay time was observed. These trends are generally expected with this combustion reaction system. The high-speed imaging showed nonhomogeneous combustion in the system; however, most of the light emissions were outside the visible light range where the camera is designed for. The results were compared to predictions of two combustion chemical kinetic mechanisms: GRI v3.0 and AramcoMech v2.0 mechanisms. In general, both mechanisms did not accurately predict the experimental data. The results showed that current models are inaccurate in predicting CO2 diluted environments for syngas combustion.

Copyright © 2017 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Pressure trace of replication study including emissions detector and camera emissions

Grahic Jump Location
Fig. 2

The data points with 20% uncertainty in our study compared to the provided data points in Ref. [4]

Grahic Jump Location
Fig. 3

Pressure trace of an experiment using mixture 2 including emissions detector and camera emissions

Grahic Jump Location
Fig. 4

These images were from the experiment plotted in Fig.3. Image (a) refers to the end wall emissions at 943.92 μs. The slope method determined ignition at 947 μs. Image (b) refers to the end wall emissions at 1286.85 μs. The peak method determined ignition at 1288 μs. An artificial ring was placed to show the circumference of the shock tube.

Grahic Jump Location
Fig. 5

Mixture 2 experimental data points with 20% uncertainty are compared with two combustion kinetic models

Grahic Jump Location
Fig. 6

Pressure trace of an experiment using mixture 3 including emissions detector

Grahic Jump Location
Fig. 7

Ignition delay time comparison between mixture 2 and mixture 3 experiments

Grahic Jump Location
Fig. 8

Pressure trace of an experiment using mixture 4 including emissions detector and camera emissions

Grahic Jump Location
Fig. 9

These images were from the experiment plotted in Fig.8. Image (a) refers to the end wall emissions at 72.23 μs. The slope method determined ignition at 78 μs. Image (b) refers to the end wall emissions at 176.6 μs. The peak method determined ignition at 176 μs. An artificial ring was placed to show the circumference of the shock tube.

Grahic Jump Location
Fig. 10

Pressure trace of an experiment using mixture 5 including emissions detector and camera emissions

Grahic Jump Location
Fig. 11

These images were from the experiment plotted in Fig.10. Image (a) refers to the end wall emissions at 239.24 μs. The slope method determined ignition at 245 μs. Image (b) refers to the end wall emissions at 343.61 μs. The peak method determined ignition at 340.5 μs. An artificial ring was placed to show the circumference of the shock tube.

Grahic Jump Location
Fig. 12

A plot of mixtures 3, 4, and 5 experiments. A change of ϕ resulted in differences in ignition delay time. These plots are compared to GRI-Mech v3.0 and AramcoMech V2.0.

Grahic Jump Location
Fig. 13

Pressure trace of an experiment using mixture 6 including emissions detector and camera emissions

Grahic Jump Location
Fig. 14

Pressure trance of an experiment using mixture 7 including the emissions detector

Grahic Jump Location
Fig. 15

A plot of mixtures 3, 6, and 7 experiments. A change of θ resulted in differences in ignition delay time under similar conditions.

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In