The AEROTRACE project provides a substantial amount of quantitative data on aircraft engine emissions of particulates, nitrogen species and hydrocarbons which will contribute to the following:
- A more complete modelling of engine exhaust plume chemistry
- Incorporation of trace species into atmospheric chemical models
- A better understanding of the impact of aircraft emissions on climate.
A summary of the main conclusions follows.
Line losses and mechanisms have been defined and will allow those making intrusive measurements of particulates to correct for line losses. A correlation between particle volume and the traditional SAE method was found. Particle numbers were found to be dependent on operating conditions but particle size distribution was found to be relatively constant and independent of operating conditions.
nitrogen Species (NOy)
A good correlation was found for NOy and HNO3 against Tau (combustor parameter). However no correlation was found for HNO2. HNO2 and HNO3 both gave a good correlation with NO2 but the levels found for these two species were low although it is known that the subsequent formation of HNO2 and HNO3 in the plume is higher.
A high proportion of the totals are in the form of low molecular weight unsaturated hydrocarbons or carbonyls, the most abundant carbonyl being formaldehyde. As expected hydrocarbon levels are strongly dependent on engine thrust with significant amounts being emitted at idle conditions. Change of fuel type influences the hydrocarbon levels but not the carbonyl levels.
Funding SchemeCSC - Cost-sharing contracts
DE2 8BJ Derby