Open AccessChemical ionization mass spectrometric measurements of SO 2 emissions from jet engines in flight and test chamber operations
Author(s) -
Hunton D. E.,
Ballenthin J. O.,
Borghetti J. F.,
Federico G. S.,
Miller T. M.,
Thorn W. F.,
Viggiano A. A.,
Anderson B. E.,
Cofer W. R.,
McDougal D. S.,
Wey C. C.
Publication year - 2000
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2000jd900383
Subject(s) - aerosol , environmental science , jet fuel , jet engine , jet (fluid) , plume , turbofan , sulfur dioxide , altitude (triangle) , mass spectrometry , meteorology , nuclear engineering , atmospheric sciences , chemistry , analytical chemistry (journal) , aerospace engineering , physics , environmental chemistry , mechanics , engineering , inorganic chemistry , geometry , mathematics , chromatography
We report the results of two measurements of the concentrations and emission indices of gas‐phase sulfur dioxide (EI(SO 2 )) in the exhaust of an F100–200E turbofan engine. The broad goals of both experiments were to obtain exhaust sulfur speciation and aerosol properties as a function of fuel sulfur content. In the first campaign, an instrumented NASA T‐39 Sabreliner aircraft flew in close formation behind several F‐16 fighter aircraft to obtain near‐field plume composition and aerosol properties. In the second, an F‐100 engine of the same type was installed in an altitude test chamber at NASA Glenn Research Center where gas composition and nonvolatile aerosol concentrations and size distributions were obtained at the exit plane of the engine. In both experiments, SO 2 concentrations were measured with the Air Force Research Laboratory chemical ionization mass spectrometer as a function of altitude, engine power, and fuel sulfur content. A significant aspect of the program was the use of the same fuels, the same engine type, and many of the same diagnostics in both campaigns. Several different fuels were purchased specifically for these experiments, including high‐sulfur Jet A (∼1150 ppmm S), low‐sulfur Jet A (∼10 ppmm S), medium‐sulfur mixtures of these two fuels, and military JP‐8+100 (∼170 and ∼300 ppmm S). The agreement between the flight and test cell measurements of SO 2 concentrations was excellent, showing an overall precision of better than ±10% and an estimated absolute accuracy of ±20%. The EI(SO 2 ) varied from 2.49 g SO 2 /kg fuel for the high‐sulfur fuel in the test chamber to less than 0.01 g/kg for the lowest‐sulfur fuel. No dependence of emission index on engine power, altitude or simulated altitude, separation distance or plume age, or the presence of contrails was observed. In all experiments the measured EI(SO 2 ) was consistent with essentially all of the fuel sulfur appearing as gas‐phase SO 2 in the exhaust. However, accurate determination of S(IV) to S(VI) conversion was hampered by inconsistencies in the assays of total fuel sulfur content.