TY - JOUR
T1 - Measurements of ensemble averaged flame dynamics using spatially resolved analysis
AU - Ranalli, J. A.
AU - Martin, C. R.
AU - Vandsburger, U.
N1 - Funding Information:
The authors acknowledge the support of the U.S. Department of Energy through the University Turbine Research Program. Author J.A. Ranalli would also like to thank the U.S. Department of Defense for support through the National Defense Science and Engineering Graduate Fellowship.
PY - 2011/10
Y1 - 2011/10
N2 - When applying flame sheet models to predict the dynamics of turbulent flames, it is common to model turbulence using ensemble averaging of the velocity. Measurements of the flame dynamics were made to support use this type of methodology, by measuring the dynamic volume of the flame using phase averaged images of the CH* chemiluminescence. The dynamics agreed with the common behavior described in the literature, namely frequency scaling according to Strouhal number based on flow convective timescales. However, slightly different timescales were observed for the response magnitude and phase, indicating the possibility of different scaling mechanisms at work between these phenomena. The flame heat release rate dynamics were found to be identical to the dynamic response of the flame volume to inlet velocity perturbations, suggesting a simple proportionality between heat release rate and the flame volume. This result supports the use of ensemble averaging for modeling of the turbulent velocity for predictions of flame dynamics.
AB - When applying flame sheet models to predict the dynamics of turbulent flames, it is common to model turbulence using ensemble averaging of the velocity. Measurements of the flame dynamics were made to support use this type of methodology, by measuring the dynamic volume of the flame using phase averaged images of the CH* chemiluminescence. The dynamics agreed with the common behavior described in the literature, namely frequency scaling according to Strouhal number based on flow convective timescales. However, slightly different timescales were observed for the response magnitude and phase, indicating the possibility of different scaling mechanisms at work between these phenomena. The flame heat release rate dynamics were found to be identical to the dynamic response of the flame volume to inlet velocity perturbations, suggesting a simple proportionality between heat release rate and the flame volume. This result supports the use of ensemble averaging for modeling of the turbulent velocity for predictions of flame dynamics.
UR - http://www.scopus.com/inward/record.url?scp=79961004787&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79961004787&partnerID=8YFLogxK
U2 - 10.1016/j.expthermflusci.2011.05.009
DO - 10.1016/j.expthermflusci.2011.05.009
M3 - Article
AN - SCOPUS:79961004787
VL - 35
SP - 1409
EP - 1417
JO - Experimental Thermal and Fluid Science
JF - Experimental Thermal and Fluid Science
SN - 0894-1777
IS - 7
ER -