EMPI - Reactive Fluids

Soot formation is an important problem related to combustion. The soot produced is toxic and contributes to global warming. Despite decades of research, soot formation is not yet fully understood. Shock tubes and a pyrolysis burner provide precisely defined conditions for studying soot formation. Both the soot formation of different starting materials and the influence of additives are investigated. The main detection methods used are laser extinction (determination of the soot volume fraction) and laser-induced incandescence (particle sizes and soot volume fraction). The influence of temperature changes during soot formation is determined by temperature measurements using CO-IR thermometry. The measured soot volume fractions can be compared to simulated soot volume fractions using a kinetics model with different BINs representing soot.

Another important study focus is the soot inception. The transition from the gas phase to large molecules and ultimately soot particles is studied in a shock tube with a kinetics spectrometer, with laser induced fluorescence (LIF), and with laser induced incandescence exploiting the variation in absorption, fluorescence, and incandescence properties of the species along the path to soot.