Design and simulation of gas burner ejectors

Carbon Resources Conversion

卷:4

Florian Wesenauer¹  Michael Harasek¹  Bernhard Streibl¹  Christian Jordan²  Stefan Puskas³  Mario Pichler³  Franz Winter³ 

[1] Bioscience Engineering, TU Wien, Getreidemarkt 9/166, 1060 Vienna, Austria;

[2] Corresponding author.;

[3] Institute of Chemical, Environmental &

关键词: Self-ignition;    Flammability limits;    Reacting jet;    Ejector;    Jet pump;    Computational fluid dynamics;   

DOI  :  

来源: DOAJ

【 摘 要 】

Ignition within gas burner ejectors can lead to off design conditions and has significant influence on the burner behavior. Thus ignition in the ejector should be prevented. In the present study the influence of combustion reactions on the performance of gas burner injectors is investigated. To investigate if ignition is possible, simulated ignition delay times, using a detailed reaction mechanism, are compared to predicted mean residence times of the gas in the ejector. Gas burner ejectors are designed using one dimensional analytic equations, based on energy and momentum conservation equations and conventional isentropic equations. 1D results are compared to 2D computational fluid dynamics (CFD) simulations, to take into account non-ideal mixing effects along the ejector. Results are validated with experiments with air at room temperature. 1D results show very good agreement not only with CFD simulations for the case of non-reactive flows, but also with performed experiments.It is shown that the assumption of ideal mixing along the ejector and thus the comparison of the ignition delay time to the gas mean residence time, to predict ignition in the ejector, is not valid. Ignition in the ejector is possible, even if the ignition delay time is more than thirty times higher than the mean residence time. In addition to that, it is shown, that ignition and the choice of reaction mechanism have significant influence on the predicted gas burner ejector performance. Thus, the accurate prediction of ignition delay time and the use of a detailed reaction kinetic are mandatory to correctly predict the burner ejector behavior.

【 授权许可】

Unknown