n-Heptane cool flame chemistry: Unraveling intermediate species measured in a stirred reactor and motored engine

n-Heptane cool flame chemistry: Unraveling intermediate species measured in a stirred reactor and motored engine

​n-Heptane cool flame chemistry: Unraveling intermediate species measured in a stirred reactor and motored engine

Z. Wang, B. Chen, K. Moshammer, D.M. Popolan-Vaida, S. Sioud, V. S. B.i Shankar, D. Vuilleumier, T. Tao, L. Ruwe, E. Bräuer, N. Hansen, P. Dagaut, K. Kohse-Höinghaus, M.A. Raji, S.M. Sarathy

Combustion and Flame, 187, 199-216 (2018)​
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Z. Wang, B. Chen, K. Moshammer, D.M. Popolan-Vaida, S. Sioud, V. S. B.i Shankar, D. Vuilleumier, T. Tao, L. Ruwe, E. Bräuer, N. Hansen, P. Dagaut, K. Kohse-Höinghaus, M.A. Raji, S.M. Sarathy
n-heptane, Auto-oxidation, Peroxides, Synchrotron VUV photoionization mass spectrometry, APCI Orbitrap mass spectrometry
2018

This work identifies classes of cool flame intermediates from n-heptane low-temperature oxidation in a jet-stirred reactor (JSR) and a motored cooperative fuel research (CFR) engine. The sampled species from the JSR oxidation of a mixture of n-heptane/O2/Ar (0.01/0.11/0.88) were analyzed using a synchrotron vacuum ultraviolet radiation photoionization (SVUV-PI) time-of-flight molecular-beam mass spectrometer (MBMS) and an atmospheric pressure chemical ionization (APCI) Orbitrap mass spectrometer (OTMS). The OTMS was also used to analyze the sampled species from a CFR engine exhaust. Approximately 70 intermediates were detected by the SVUV-PI-MBMS, and their assigned molecular formulae are in good agreement with those detected by the APCI-OTMS, which has ultra-high mass resolving power and provides an accurate elemental C/H/O composition of the intermediate species. Furthermore, the results show that the species formed during the partial oxidation of n-heptane in the CFR engine are very similar to those produced in an ideal reactor, i.e., a JSR. ​
DOI: 10.1016/j.combustflame.2017.09.003