Experimental Study of Soot Formation for Practical Fuels

Soot formation consists of complex and concurrent processes which are not completely understood yet. Experimental study of soot formation is required for model validation and also for testing new hypothesis about the effects of different flow parameters such as temperature and fuel composition on soot formation. The soot experimental group has two main goals: 1. provide high quality data for model validation ,and  2. use different diagnostic techniques to investigate different processes of soot formation.

We use several experimental techniques to measure soot concentrations, flame and soot temperature and size/size distributions of soot particles  in laminar coflow diffusion flames of the target fuels. The advantage of using several techniques to measure a single property of a flame is that by using different experimental techniques we can understand the strengths and weaknesses of each method and this knowledge helps us to better validate the models and also to better understand soot formation.   We use the following techniques in our group:

 

• Laser Extinction method with different wavelengthes to measure soot volume fraction 

 

• Laser Induced Incandescence method to measure soot volume fraction and the sizes of soot primary particles

 

• Soot Spectral Emissions method to measure soot volume fraction and soot temperature

 

• Rapid thermocouple insertion method to measure  flame temperature

 

• Thermophoretic Sampling method to measure the size and morphology of soot particles

 

• Laser Scattering method to measure the volume fraction and size distribution of soot particles

 

• Specious Sampling to measure the concentrations of different important specious in the flames
  

  5-decene, 1-decene, n-decane, and biodiesel surrogate flames, Kholghy et al, P Combust Inst, 2016