Eventos Anais de eventos
ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
Estimation of Double Tsuji flames dimension based on experimental, analytical and numerical results
Submission Author:
Jean Barbosa , SP
Co-Authors:
Jean Barbosa, José Carlos de Andrade, Matheus P. Severino, Vinicius Maron Sauer, Fernando Filho Fachini
Presenter: Fernando Filho Fachini
doi://10.26678/ABCM.ENCIT2022.CIT22-0251
Abstract
This work goal is the estimation of Double Tsuji flame dimension using an experimental setup together with a 2D simulation through the commercial solver Fluent® and a scale model. This new configuration consists of a porous cylindrical burner, ejecting fuel radially and uniformly, in the middle of two impinging jets of oxidizer. It forms two counterflow regions, similar to the classical Tsuji burner, one upward and the other downward of the burner. The flame dimensions based on the scale model are related to a flame shape factor, the air-fuel stoichiometric relation and two Péclet numbers, one relative to the burner and the other to the impinging flow. In the numerical simulation, GRI3.0 was used as the kinetic mechanism and Fick’s law for the species transport model. As this is a new burner configuration, besides the flame dimension estimation, it is important to confirm if Fluent® can be used to describe the physical aspects of the double Tsuji flame. Three fuel flow velocities and one oxidizer flow velocity are considered in the experimental tests. The experimental flame measurement was performed using a pixel-to-distance calibration on the flame photographic images. Due to the flame thickness, there is a region of increase in pixel value, so the flame is located between the two coordinates of the half maximum pixel value, named the lower and upper branches. The results show that the simplified scale model estimates well the location of the lower branch despite its simplicity. The highest deviation for the flame’s length was 17.56 % and for the flame’s height was 34.15 %, both for the biggest fuel flow velocity. The numerical simulation shows a better agreement with the experimental results than the scale model. In the counterflow region, the entire consumption of fuel and oxidizer is located between the two experimental branches. Moreover, the temperature peak is near the location of the maximum pixel value. However, the numerical simulation overestimated the flame length because it is not considered the oxidizer transportation in the z-axis, that will result in a more compact flame.
Keywords
double Tsuji burner, double Tsuji flame, laminar, Diffusion Flame
