In the diffusion flame, does the region of maximum temperature (which defines the stoichiometric flame front) correspond to the zone of maximum luminosity? Can you explain your observation? What causes the flame to be luminous?What is the source of the mass that ends up as soot? How does oxygen affect soot formation and/or destruction? Does the flame temperature influence soot formation under constant fuel/oxidizer conditions? Why? Discuss the importance of radiative heat transfer from a flame and the role that soot may play in this process.

Discuss how the measurements you have made relate to the combustion of fuel in the Otto cycle internal combustion engine. Do these measurements provide any information that relates to NOx formation or CO emissions? Refer to the Otto cycle section of this manual.