Emissions Flashcards
(16 cards)
What types of emissions do we have from normal diesel combustion?
CO, NOx, Soot and PM, unburned hydrocarbons, SOx and CO2
About how much of exhaust is pollutants?
0.3%
Why is CO created?
There are pockets whit little air in chamber, this creates CO
Soot is formed when
you have a high local equivalence ratio
NOx is formed when
combustion temperature is really high
What is the dangers of NOx?
irritates longs, poisonous for plants, contributes to accis rain, ozone, contributes to smog
Who is CO dangerous for?
People, not planet
How is NO-chemicals created
Nitrogen rarely reacts whit other compounds, but can do so at really high temperatures and in the flame front as N2 reachs with CH radicals (called NO and prompt NO)
what is soot?
Soot is graphite that clump together and make particles as a result of incomplete combustion
What is PM?
Extremely small particles. Some are soot, some are engine oil matter and some other things…
Why can you not eliminate soot AND NOx?
NOx and soot can not be removed. If you add more heat, more NOx is created, if you increece eqvivalence ratio more soot is created.
What is the danger of unburned hydrocarbons?
Really bad for healt
What are the main ways of controlling emissions?
control of local temperature, local oxygen consentration are the main points.
How to avoid CO?
High temp, lean combustion, good mixing, can add water
What is PM?
The sum of all small particles in the exhaust
What are the dangers of unburned hydrocarbons.
damages long tissue as if forms in to ozone. Ozone is especially dangerous for children.
