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http://dx.doi.org/10.4491/KSEE.2012.34.2.103

A Study on the Flow Entrainment Characteristics of a Coaxial Nozzle Used in a MILD Combustor with the Change of Nozzle Position and Flow Condition  

Shim, Sung-Hoon (Korea Institute of Machinery & Materials Energy)
Ha, Ji-Soo (Environmental Science Department, Keimyung University)
Publication Information
Journal of Korean Society of Environmental Engineers / v.34, no.2, 2012 , pp. 103-108 More about this Journal
Abstract
A MILD (Moderate and Intense Low oxygen Dilution) combustor decreases NOx formation effectively during the combustion process and NOx formation is affected significantly by the exhaust gas entrainment rate toward fuel and air. The present study focused on the new MILD combustor, which has coaxial cylindrical tube. The outside tube of the new MILD combustor corresponds to the exhaust gas passage and the inner side tube is the furnace passage. The connection pipe is set between the outer side and the inner side tubes and coaxial air nozzle is inserted at the center of the connection pipe. A numerical analysis is accomplished to elucidate the characteristics of exhaust gas entrainment toward the inner furnace with the changes of air nozzle exit velocity, nozzle diameter, nozzle exit position and exhaust gas side pressure. The entrainment rate is proportional to the square root of air nozzle exit velocity and negatively proportional to the pressure difference between the exhaust gas side and furnace side pressures. The effect of air nozzle exit position is not considerable on the exhaust gas entrainment.
Keywords
MILD Combustion; Air Nozzle Exit Velocity; Air Nozzle Exit Position; Air Nozzle Diameter; Pressure Difference;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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