Spatial structure and NO formation of a laminar methane–nitrogen jet in hot coflow under MILD conditions: A spontaneous Raman and LIF study

3D DNS of MILD combustion: A detailed analysis of heat loss effects, preferential diffusion, and flame formation mechanisms

“…One of the most used experimental setups to study MILD combustion is the jet in hot coflow (JHC) configuration. JHC was studied under both laminar [8,9] and turbulent [10,11] conditions. In this type of burner, a fuel jet is issued into a hot and diluted coflow, and the lifted flame is stabilized by autoignition.…”

Understanding and Interpreting Laser Diagnostics in Flames: A Review of Experimental Measurement Techniques

“…Concentrations and images of major, intermediary and radical combustion species in jet flames in hot and diluted coflows have been obtained through single-point Rayleigh-Raman-LIF (Cabra et al, 2002(Cabra et al, , 2005Dally et al, 2002;Dunn et al, 2009;Sepman et al, 2013) and planar LIF (Medwell et al, 2007(Medwell et al, , 2008(Medwell et al, , 2009bGordon et al, 2008Gordon et al, , 2009Dunn et al, 2009;Oldenhof et al, 2011;Oldenhof et al, 2012;Masri, 2011, 2012;Arndt et al, 2012Arndt et al, , 2013Sidey and Mastorakos, 2015;Ye et al, 2016Ye et al, , 2017Ye et al, , 2018Kruse et al, 2019) measurements.…”

“…Single-point Rayleigh-Raman-LIF experiments performed in JHC burners have provided quantitative ensemble data of simultaneously measured temperature, major species and mixture fraction via Rayleigh-Raman, with CO-and OH-LIF (Cabra et al, 2002(Cabra et al, , 2005Dally et al, 2002;Dunn et al, 2009;Sepman et al, 2013), often using an experimental configuration similar to that shown in Figure 2. The configuration in Figure 2 shows a 532 nm beam for Rayleigh-Raman measurements and three UV beams for CO-, OH-and NO-LIF, as well as lenses and photomultiplier tubes (PMTs) for signal detection.…”

“…Fundamental studies of these flames have not only provided significant insight into autoignition processes, but have been used to generate extensive datasets in simplified configurations for validating turbulence-chemistry interaction models for numerical modeling of combustion systems. Fundamental studies of laminar and turbulent jet flames issuing into high temperature, low oxygen environments have been undertaken in jet in hot coflow (JHC) burners (Dally et al, 2002;Medwell et al, 2007Medwell et al, , 2008Oldenhof et al, 2010Oldenhof et al, , 2011Oldenhof et al, 2012;Medwell and Dally, 2012a;Sepman et al, 2013;Ye et al, 2016Ye et al, , 2017Ye et al, , 2018Evans et al, 2017bEvans et al, , 2019aKruse et al, 2019), hot cross-flow burners (Sidey and Mastorakos, 2017), vitiated coflow burners (VCBs) (Cabra et al, 2002(Cabra et al, , 2005Gordon et al, 2008Gordon et al, , 2009Macfarlane et al, 2018Macfarlane et al, , 2019Ramachandran et al, 2019), and partially premixed jet burners (PPJBs) (Dunn et al, 2007a;Dunn et al, 2009), as have spray flames in hot coflow burners (Correia Rodrigues et al, 2015a,b;Wang et al, 2019b). In each case, fresh fuel issues from a jet into a stream of hot gas generated by lean premixed flames, resulting in 15% O 2 (by vol.).…”

“…Such improved understanding these transitions-and the structure of the upstream flames leading to their formation-may be achieved through targeted laser-diagnostics studies and subsequently validated, complementary numerical modeling. The high fidelity data that laser diagnostics can provide allows for the detailed study of reactive structures across the broad range of spatial and temporal scales in different optically-accessible JHC burners and reactors (Plessing et al, 1998;Cabra et al, 2002Cabra et al, , 2005Dally et al, 2002;Medwell et al, 2007Medwell et al, , 2008Gordon et al, 2008Gordon et al, , 2009Oldenhof et al, 2010Oldenhof et al, , 2011Oldenhof et al, 2012;Medwell and Dally, 2012a;Sepman et al, 2013;Sorrentino et al, 2015Sorrentino et al, , 2016Ye et al, 2016Ye et al, , 2017Ye et al, , 2018Evans et al, 2017bEvans et al, , 2019aSidey and Mastorakos, 2017;Macfarlane et al, 2018Macfarlane et al, , 2019Kruse et al, 2019;Ramachandran et al, 2019). Laser diagnostics a provide means to investigate the small-scale and distributed reaction zones in macroscopically-near-homogeneous MILD combustion conditions.…”