Multiple solutions for structures of laminar counterflow spray flames (Q979528)

Summary: A similarity transformation of the two-dimensional, governing gas-phase equations enables the consideration of detailed chemical reactions in the gas phase of dilute laminar counterflow spray flames. Two different spray flame structures in the low-strain regime for liquid fuel sprays in air for identical boundary conditions are reported: one flame structure comprises two chemical reaction zones where one flame resides in the primary vaporisation regime on the spray side of the configuration, whereas the second chemical reaction zone occurs on the gas side of the counterflow configuration. In the second flame structure, the gas-side flame is extinguished and the spray flame structure consists of a single reaction zone on the spray side of the configuration. These multiple structures persist at low strain. At high strain, the gas-sided flame extinguishes and a unique solution is obtained. Multiple solutions of the governing equations have been postulated before, but this is the first report of multiple solutions.