The effect of n-butanol addition on the sooting limit of n-heptane was studied by using a micro flow reactor with a controlled temperature profile. Pure n-heptane and n-butanol + n-heptane (10:90) were employed in this study. The experiments were conducted for various equivalence ratios, φ = 1.5 - 3.5. The inlet mean velocity was U0 = 10 cm/s, maximum wall temperature was 1300 K under atmospheric pressure condition. The results showed three types of flame and soot responses: flame, flame with soot and only soot. In addition, the experimental results showed that the presence of n-butanol extended the sooting limit. Pure n-heptane showed soot starting to form at φ= 1.6 whereas for 10% additional nbutanol, it started at φ=1.9. As the equivalence ratio, φ increases, experimental results showed more soot moving to lower temperatures. Computational results also showed Pyrene, A4 mole fraction increased as the equivalence ratio increases. Furthermore, soot was formed in a range of 1200 K to 1300 K. At higher equivalence ratios (3 and 3.5), experiments showed similar starting point of soot at lower temperature for pure n-heptane and blended fuel with 10% mole percentage addition of n-butanol. Computational A4 mole fraction was slightly decreased when 10% of n-butanol was introduced to the n-heptane. In computational results, a large difference in A4 mole fraction was shown between higher equivalence ratio (3.0 and 3.5) and lower equivalence ratio (1.5 to 2.0). Further study on chemical reactions focusing on A4 reaction is necessary in order to accurately describe the tendency of soot formation.
|Number of pages||5|
|Journal||ARPN Journal of Engineering and Applied Sciences|
|Publication status||Published - 2017 Aug 1|
- Micro combustor
- Oxygenated fuel
- Soot formation
ASJC Scopus subject areas