Tootfinder

Large eddy simulation of turbulent swirl-stabilized flames using the front propagation formulation: impact of the resolved flame thickness
Ruochen Guo, Yunde Su, Yuewen Jiang
https://arxiv.org/abs/2602.21940 https://arxiv.org/pdf/2602.21940 https://arxiv.org/html/2602.21940
arXiv:2602.21940v1 Announce Type: new
Abstract: This work extends the front propagation formulation (FPF) combustion model to large eddy simulation (LES) of swirl-stabilized turbulent premixed flames and investigates the effects of resolved flame thickness on the predicted flame dynamics. The FPF method is designed to mitigate the spurious propagation of under-resolved flames while preserving the reaction characteristics of filtered flame fronts. In this study, the model is extended to account for non-adiabatic effects and is coupled with an improved sub-filter flame speed estimation that resolves the inconsistency arising from heat-release effects on local sub-filter turbulence. The performance of the extended FPF method is validated by LES of the TECFLAM swirl-stabilized burner, where the results agree well with experimental measurements. The simulations reveal that the stretching of vortical structures in the outer shear layer leads to the formation of trapped flame pockets, which are identified as the physical mechanism responsible for the secondary temperature peaks observed in the experiment. The prediction of this phenomenon is shown to be strongly dependent on the resolved flame thickness, when the filter size is used for modeling sub-filter flame wrinklings. Without proper modeling of the chemical steepening effects, the thickness of the resolved flame brush is over-predicted, causing the flame consumption rate to be under-estimated. Consequently, the flame brush detaches from the outer shear layer, resulting in a failure to capture the flame pockets and the associated secondary temperature peaks.
toXiv_bot_toot

Hš vinte anos atršs, eu achava que 480p era uma resolução ótima para vídeos e que somente filmes muito específicos (com fotografia excepcional) justificavam o uso de resolução de 720p, que ocupava muito espaço no HD/CD. Mas agora hš pouco estava assistindo um videoclip da Loreena McKennitt em resolução 480p na minha TV de 42 polegadas e mal conseguia distinguir as imagens.
Em parte isso é porque nossos cérebros ficaram muito acostumado a imagens em alta resolução. Mas, principalmente, c…

Wollt ihr den AI Slop sehen, wegen dem der Zürcher Bauernverband wohl demnächst einen wütenden Brief von Nintendo bekommt? 🤦‍♀️⚖️
#Bauernlobby

Following federal cuts to history-focused organizations, the president of the Canadian Historical Association, Colin Coates, sent this letter to Marc Miller, the Minister of Canadian Identity and Culture.
One thing might not be obvious: Coates's reference to Carney's recent Quebec City speech suggests Canadians' need for historical context right now. He doesn't agree with Carney's claims. In fact, most Canadian historians would dispute them.