Parametric Study of Vortex Generator for LPG Combustion Characteristics on a Slot Burner

The parametric study of a vortex generator (VG) was investigated by numerical model and experiment to improve the combustion characteristics of liquified petroleum gas (LPG) on a slot burner. The composition of synthetic LPG is 70% propane (C₃H₈) and 30% butane (C₄H₁₀), with a 20 L/min airflow. The investigated parameters were aspect ratios (AR), angle, direction (CW/CCW) and distance between vortex generators (S) with cylindrical bluff bodies. These parameters are used to improve the combustion characteristics on a slot burner. As the simulated results, the VG with 60° angle, CW direction, AR=0.4, and S=1.0 mm could improve the combustion characteristics due to a well-mixed between fuel and air and the uniform temperature distribution. The experimental results showed a vortex generator at a 60° angle, CW direction, AR=0.4, and 2.0 mm between the VG were optimal. When combined with a cylindrical-shaped bluff body, the air and fuel were well-mixed due to higher air velocity and extended time for mixing. This promoted complete combustion and made the soot free length fraction (SFLF) of the flame higher. The average temperature above the burner was greater, and the flame range in the combustion diagram is wider. The parameters of VG could affect and improve the LPG combustion characteristics.