Effect of Molecular Structure on Soot Formation Characteristics of Aviation Turbine Fuels

The smoke point has been shown to be quantitatively related to the molecular structure of hydrocarbon fuels. A fast technique of determining the molecular composition of commercial and experimental fuels, in terms of carbon type structure, by using proton nuclear magnetic resonance (¹H NMR) spectrometry, has been described. By measuring the smoke point soot yields of a laminar diffusion flame with a group of fuels—all having a constant hydrogen-to-carbon ratio—it has been shown that neither the smoke point nor the hydrogen-to-carbon ratio alone can describe the sooting propensity of turbine fuels. Obtained results indicate that smoke points and hydrogen-to-carbon ratio are complementary to each other in describing the sooting propensities of turbine fuels. This has been further tested using the available data in literature obtained from gas turbine combustors and diffusion flames.