Aspects of combustion theory that directly relates to the Volkswagen crisis.
Date: Tue 6 Oct 2015 11am – 12pm London
Location: Lecture Theatre 10, F Floor, Dept Civil & Structural Eng, Mappin Building
In order to work efficiently petrol and diesel internal combustion engines normally operate under precisely controlled fuel-lean combustion conditions. However, the fundamental combustion chemistry leads to NOx production. This problem is particularly acute for modern diesel engines, which attain higher maximum temperatures due to large compression ratios. Less efficient fuel rich combustion on the other hand tends to reduce any combustion-produced NOx to N2. It is much less efficient. Therefore to meet highly stringent NOx emission targets the propensity would be to run diesel engines under less-efficient conditions for the test period. In this lecture fundamental structure of flames is reviewed, as is fundamental flame nitrogen chemistry.
The answer to this dilemma may be to introduce additional selective catalytic reduction devices – which would entail a major redesign of diesel engines and adding additional costs.