Investigating coherent streaks in wildfires via heated plates in crosswind

Identifying Characteristics of Wildfire Towers and Troughs

“…Moreover, the tower trough structures are persistently present even in well-developed fires, not only in transition flows. Other authors have found similar results on inclined plates [13,24], and some researchers have noted that the counter-rotational vortices have some similarities to Görtler vortices [2,[8][9][10][19][20][21]. It is important to note that the tower and trough pattern is similar but not identical to Görtler vortices, which arise as a result of fluid impinging upon a curved surface (i.e., Görtler vortices are a combination of forward momentum and centrifugal force, while the heated plate towers and troughs arise from forward momentum and the force due to buoyancy) [25][26][27].…”

“…The observation of towers and trough-like structures associated with strong buoyancy driven environments can be traced back to several studies involving heated plates [4][5][6][7]. Stationary diffusion flames have also been used in efforts to study the interactions between forward momentum and buoyancy without the additional complexities of combustion [8][9][10]. Boundary layer instabilities could develop into counter-rotating streamwise vortices which were associated with the visible tower and trough pattern in wind-driven fire scenarios.…”

“…In the wind tunnel experiments involving flat, isothermally heated plates and no subsequent diffusion flame, it was demonstrated that the spacing and width of the counter-rotational vortices both have a lognormal distribution. Interestingly, the spacing and width grow as streamwise distance increases along the heated plate, and the spacing and width of vortices decrease considerably as plate temperature increases and (to lesser degree) as wind speed increases [8,13,14].…”

On the use of compact thermal cameras for quantitative wildfire monitoring

“…) Chapter 5 -Decision Support Systems and Tools Thermal infrared cameras have seen an outstanding development in the last few years, on both market ends. On the one hand, high-end devices that work at high speed and with high resolution are allowing unprecedented studies of fire behavior and characteristic fire structures at different scales (McAllister and Finney 2017;Miller et al 2017). On the other, cameras with basic capabilities have become smaller, lighter and cheaper than ever.…”