Flame Attachment in Flame Spread

Flame attachment is a subject that can be studied in many contexts and which has a relatively long history. All diffusion flames are ultimately attached somewhere along their length to one or more surfaces. Depending on the type of particular application, the attachment region may be important to the behavior of the entire flame. Flame spread over solid fuels is ones area in which flame attachment is apparently of central importance. It is widely believed, through it has not yet beer conclusively demonstrated, that the attachment region-alternately called the 'flame tip,' 'flame foot,' 'attachment point,' and etc. -controls the entire spread process. Flame spread is an important problem for both practical and academic reasons. On the practical level, one wishes to prevent or, at worst, control unwanted flame spread over combustible materials; to know what levels of heat flux are necessary to sustain flame spreading once it has begun; to design materials that are as minimally hazardous as possible; and to devise extinguishment methods that are both sound and useful. Academically, flame spread is one of the most difficult problems of combustion theory, combining a fully interacting multidimensional transient gas and solid phase problem with chemistry, heat transfer, radiation and material properties that may change during spreading. For this reason, it has been a challenge for scores of combustion researchers.