Air Jet Assisted Combustion of Oil Diffusion Flames: Effects of Injection Location and Excess Air Factor

Authors

Moustafa Ahmed GamalEldin, Continuous Combustion Laboratory, Mechanical Power Engineering Department, Faculty of Engineering - Mataria, Helwan University, Cairo 11718, EgyptFollow
Neama Youssef Ramadan, Continuous Combustion Laboratory, Mechanical Power Engineering Department, Faculty of Engineering - Mataria, Helwan University, Cairo 11718, Egypt
Ahmed Mohamed Abdulnaim, Continuous Combustion Laboratory, Mechanical Power Engineering Department, Faculty of Engineering - Mataria, Helwan University, Cairo 11718, EgyptFollow
Ahmed Abdelnasser Adam, Continuous Combustion Laboratory, Mechanical Power Engineering Department, Faculty of Engineering - Mataria, Helwan University, Cairo 11718, Egypt
Ahmed Abdulrazik Emara, Continuous Combustion Laboratory, Mechanical Power Engineering Department, Faculty of Engineering - Mataria, Helwan University, Cairo 11718, Egypt
Hany Ahmed Moneib, Continuous Combustion Laboratory, Mechanical Power Engineering Department, Faculty of Engineering - Mataria, Helwan University, Cairo 11718, EgyptFollow

Corresponding Author

Moustafa Ahmed GamalEldin

Document Type

Original Study

Subject Areas

Mechanical Engineering

Keywords

Air jet assisted combustion; Moderate Intense Low Oxygen Dilution (MILD combustion); Lean partially premixed flame; Jet in crossflow; Oil diffusion flames; Disc stabilized burner; Jet mixing

Abstract

This study investigates a novel methodology for a coaxial disc stabilized burner with a central jet oil spray. It introduces multiple air injection jets within the burner gun's exit section, promoting earlier fuel vaporization and rapid fuel-air mixture formation in the premixing zone. This directly contributes to improved overall combustion efficiency and reduced exhaust emissions. The focus lies on identifying the optimal location for the air injection jets (fixed load, constant jet momentum, and angle) within the exiting premixing zone of the burner gun. In-flame measurements are conducted inside a cylindrical combustor at different air injection locations and varying excess air factor. The measurements cover: (i) the variations in the thermal flame structure in terms of the axial and radial variations of the mean gas temperature, (ii) heat flux, and (iii) exhaust emissions. Results demonstrate significant improvements in oil diffusion flame performance through reduced flame length, temperature uniformity, soot oxidation, and lower pollutant emissions. The combustion mode shifts from a diffusion flame to a lean partially premixed flame, or a moderate or intense low-oxygen dilution combustion regime based on air injection jet parameters. The optimal location for air injection jets is found to be at the exit plane of the premix chamber (5cm from the stabilizer disk). This injection position is associated with superior combustion efficiency (above 95%), minimal carbon monoxide emissions (under 23 ppm), and a permissible level of nitrogen oxides (NOx) emissions (about 35 ppm). While applicable to gas turbine combustion and other oil diffusion flames, further studies and simulations are necessary to optimize and validate this promising technique.

How to Cite This Article

GamalEldin, Moustafa Ahmed; Ramadan, Neama Youssef; Abdulnaim, Ahmed Mohamed; Adam, Ahmed Abdelnasser; Emara, Ahmed Abdulrazik; and Moneib, Hany Ahmed (2024) "Air Jet Assisted Combustion of Oil Diffusion Flames: Effects of Injection Location and Excess Air Factor," Trends in advanced sciences and technology: Vol. 1, Article 4.
DOI: 10.62537/2974-444X.1003
Available at: https://tast.researchcommons.org/journal/vol1/iss1/4