Experimental Study of Coflow Propane—Air Laminar Diffusion Flames at Subatmospheric Pressures
Source abstract
Abstract
The effect of pressure on the flame’s physical structure and soot formation of the coflow propane—air laminar diffusion flames was studied experimentally at subatmospheric pressures from 30 to 101 kPa. Flames with a constant fuel mass flow rate combined with two different coflow air mass flow rates were investigated at different pressures. The spatially resolved relative soot volume fraction was measured using the laser-induced incandescence (LII) method. The height of the visible flame decreased moderately as the pressure (p) reduced from 101 to 30 kPa. The maximum flame diameter increased proportionally to pn, where the exponent changed from −0.4 to −0.52 as the air-to-fuel velocity ratio decreased from 1.0 to 0.5. Strong pressure dependence of the maximum relative soot volume fraction and the normalized maximum soot mass flow were observed and could be described by a power law relationship. However, a nonmonotonic dependence of soot formation on the air-to-fuel velocity ratio was observed at all the considered pressures.
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Research context
OpenAlex topics: Combustion and flame dynamics · Advanced Combustion Engine Technologies · Vehicle emissions and performance
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
School of Materials Engineering, Changshu Institute of Technology, Changshu 215500, China
College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai 201306, China
State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026, China
Funding
National Natural Science Foundation of China
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