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.
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Filing: Paramount extends the deadline for WBD shareholders to vote on its $30-per-share offer to February 20 (Dade Hayes/Deadline)
https://deadline.com/2026/01/paramount-extends-deadline-warner-bros-discovery-netflix-1236692082/

Paramount Extends Deadline For Warner Bros. Discovery Shareholders To Back Hostile Bid
Paramount has extended the deadline for Warner Bros. Discovery shareholders to throw their support behind the company’s hostile takeover bid. The initial deadline of Wednesday has now been pushed to February 20. Paramount CEO David Ellison, along with his senior exec team and financial backers, have been meeting with WBD investors in recent weeks in […]

Urban Demons VII 👻
城市鬼魂 VII 👻
📷 Zeiss IKON Super Ikonta 533/16
🎞️ Ilford HP5 400 Plus, expired 1993
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🇺🇦 #NowPlaying on #BBC6Music's #TheMorningAfterMix
Wolf Alice:
🎵 No Hard Feelings
#WolfAlice
https://wolfalice.bandcamp.com/track/no-hard-feelings
https://open.spotify.com/track/6eJaTm3sfYirbFpibBhnRO

Chilean president declares state of catastrophe as wildfires kill at least 15. Fires blaze through 8,500 hectares, forcing 50,000 people to evacuate as firefighters struggle to extinguish flames in scorching heat: temperatures up to 38°C (100F)
https://www.thegu…

I hear Southwest's lavatories are going coin-op in FY27. 🤣
✅ Southwest Airlines Begins Assigning Chores - The Onion
https://theonion.com/southwest-airlines-begins-assigning-chores/

Southwest Airlines Begins Assigning Chores
DALLAS—Saying the decision had been reached following an extensive internal review of the company’s boarding procedures, Southwest Airlines confirmed Tuesday that passengers would now be assigned chores ahead of time. “There has always been a degree of chaos around passengers having to choose right as they’re boarding how they’re going to help keep the plane […]

From now on, whenever I am at a Chaos event with @…, you can call my DECT F-L-O-H (3564)
🥳
#dankeEventphone

A minimal wake-vortex model explains formation flight of flapping birds
Olivia Pomerenk, Kenneth S. Breuer
https://arxiv.org/abs/2602.22043 https://arxiv.org/pdf/2602.22043 https://arxiv.org/html/2602.22043
arXiv:2602.22043v1 Announce Type: new
Abstract: Collective patterns of motion emerge across biological taxa: insects swarm, fish school, and birds flock. In particular, large migratory birds form strikingly ordered V-shaped formations, which experiments and direct numerical simulations have demonstrated provide substantial energetic benefits during long-distance flight. However, the precise aerodynamic and morphological mechanisms underlying these benefits remain unclear. In this work, we develop a reduced-order model of the wake-vortex interactions between two flapping birds flying in tandem. The model retains essential unsteady flapping dynamics while remaining computationally tractable. By optimizing over a six-dimensional state space, which comprises the follower's three-dimensional relative position and three independent flapping parameters, we identify the energetically optimal leader-follower configuration of northern bald ibises. The predicted optimum agrees quantitatively with live-bird measurements. Because of its simplicity, the model allows for direct interrogation of the physical mechanisms responsible for this optimum. In particular, it isolates precisely how the follower's wing kinematics interact with the leader's wake to enhance aerodynamic efficiency. The model predicts an 11% reduction in total mechanical power for a follower in formation flight -- consistent with experimental estimates -- and shows that this saving arises from reductions in both induced and profile power, dominated by decreased profile power enabled primarily through reduced flapping amplitude and, secondarily, reduced upstroke flexion. These results provide a mechanistic explanation for the structure of V-formations and offer new insight into the aerodynamic principles governing collective flight.
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Microplastics may be quietly damaging your brain and fueling Alzheimer’s and Parkinson’s #health

Microplastics may be quietly damaging your brain and fueling Alzheimer’s and Parkinson’s
Tiny plastic particles may be quietly threatening brain health. New research suggests microplastics—now widely found in food, water, and even household dust—could trigger inflammation and damage in the brain through multiple biological pathways. Scientists estimate adults may consume about 250 grams of these particles each year, and some can accumulate in organs including the brain.

"Whoa. What? Stop. You're into Klingon acid punk?"
I have very strong feelings of affection towards Star Trek: Lower Decks 🥰 You know how kids don't have a concept of being childish and instead everything cool is awesome? Like, Trek awesome? That's how exciting it is for me to watch every episode. For instance, "We'll always have Tom Paris" (2x03) features...Tom Paris! 😁