CFD simulation of hydrogen deflagration in a vented room

[摘要] In the present work, CFD simulations of hydrogen deflagration in a real scale vented room are performed. Two ignition points were simulated: at the wall opposite to the vent (back ignition) and at the center of the chamber (center ignition). The overpressure time series and flame front velocities are compared with the experimental results. The combustion model is based on the turbulent flame speed concept. The turbulent flame speed is calculated based on a modification of Yakhot's equation, in order to account for all the main physical mechanisms which appear in hydrogen deflagrations. Special attention is given to the simulation of Rayleigh-Taylor instability. This instability occurs at the vent area and results in sudden explosion of the mixture that has been pushed outside the chamber at the initial stage of the explosion. The importance of this external explosion to the generated overpressures inside the chamber is highlighted. The agreement between experimental and computational results is satisfactory in both back ignition and center ignition cases.

[发布机构] Environmental Research Laboratory, National Center for Scientific Research Demokritos, Agia Paraskevi; 15310, Greece^1;National Technical University of Athens, School of Chemical Engineering, Heroon Polytechniou 9, Zografou; 15780, Greece^2

[效力级别] 计算机科学 [学科分类] 计算机科学（综合）

[关键词] Combustion model;Computational results;External explosion;Flame-front velocity;Hydrogen deflagration;Physical mechanism;Rayleigh-Taylor instabilities;Turbulent flame speed