We observed hydrogen of the order of 250 pm in the exhaust of a diesel engine at idling conditions measured with gas chromatography. Is this reasonable? What is a reasonable range? I have seen technical papers showing < 1% H2 in the exhaust of diesel engines in 1950s, did this change with the common rail injection?
I assume your signal is not from "free" H2 but from CxHy.
As the combustion is more complete these days (as compared with the 50s), a lower hydrogen fraction (other than H2O) doesn't come as a surprise.
BTW: while the number of particles (soot) has been about constant over the decades, the size of the particles (and thus the total mass of the soot) has significantly decreased due to advances in combustion control and fuel injection.
Hope this helps...
250 ppmH2 is high for lean condition like that.
Please try re-calibrate GC and try again.
I do not know how much the hydrogen concentration in combustion products really is because I do not have the instruments to calculate hydrogen concentration to give you a scientific and accurate answer
- Badges
- Science topic
- Similar topics
- Philosophy
- Philosophy Of Science
- Reasoning