Effects of various densities and velocities on gaseous hydrocarbon fuel on near nozzle flow field under different laminar coflow diffusion flames

Title & Authors
Effects of various densities and velocities on gaseous hydrocarbon fuel on near nozzle flow field under different laminar coflow diffusion flames
Ngorn, Thou; Jang, Sehyun; Yun, Seok Hun; Park, Seol Hyeon; Lee, Joo Hee; Chung, Suk Ho; Choi, Jae Hyuk;

Abstract
An experimental study on the flow characteristics under various laminar coflow diffusion flames was conducted with a particular focus on the buoyancy force exerted from gaseous hydrocarbon fuels. Methane ($\small{CH_4}$), ethylene ($\small{C_2H_4}$), and n-butane ($\small{C_4H_{10}}$) were used as the fuels. A coflow burner and the Schlieren imaging technique were used to observe the flow field of each fuel near the nozzle exit as well as the flow characteristics in the flames. The results show that a vortex with a density heavier than air appeared in n-butane near the nozzle exit with a strong negative buoyancy on the fuel steam. As the Reynolds number increased through the control of the fuel velocity of the n-butane flame, the vortices were greater and the vortex tips were moved up from the nozzle exit. In addition, the heated nozzle affected the flow fields of the fuel steam near the nozzle exit.
Keywords
Laminar diffusion flame;n-Butane;Recirculation zone;Reynolds number;Buoyancy;
Language
English
Cited by
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