ABSTRACT
This paper presents the experimental results of a cylindrical combustor under flameless combustion with liquid fuel (LF) for three different configurations. The three flow field configurations constituted varying combinations of tangential air inlet ports and a central atomizing fuel injection nozzle to examine their effects on the FC characteristics of LF. They include optimal configuration (case 1) and two other configurations (case 2 and 3). The results for the three configurations are compared based on temperature distribution visual observation, and emissions. The combustor operated with ethanol in the range of thermal inputs of 21 to 11.3 kW with constant air (5.66 g/s) at ambient conditions. Low NOx and CO emissions, better temperature uniformity, and invisible flame have been observed in the flameless mode for the three configurations compared to the conventional flame. Whereas case 1 recorded lower NOx and CO emissions and higher temperature uniformity over the entire volume of the combustor as compared to the other two cases and referred to an optimal configuration for the present combustor.
Acknowledgments
The first author would like to thank the Nigerian Government through the tertiary Education Trust Fund (TETFUND) for the scholarship award and gratefully acknowledge the financial support of the UTM-high impact research grant vote 09G05. We are also grateful for the support received from the HiREF laboratory members and the panel reviewers’ valuable comments.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Nomenclature
CDC | = | Colorless Distribution Combustion |
HiREF | = | High-speed Reacting Flow |
HiTAC | = | High-Temperature Air Combustion |
LFFC | = | Liquid Fuel Flameless Combustion |
MILD | = | Moderate Or Intense Low-Oxygen Diluted |
O2 | = | Oxygen Concentration |
FF | = | Forward Flow |
FC | = | Flameless Combustion |
FLOX | = | Flameless Oxidation |
LF | = | Liquid Fuel |
Φ | = | Equivalence Ratio |
RF | = | Reversed Flow |