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CO/H2 (ratios i.e. water gas shift equilibria) in exhaust gases produced from the combustion of pure isooctane, methanol, and methane in a pulse flame combustor were measured. Measured CO/H2 ratios were directionally consistent with C/H ratios of the respective fuels. The average CO/H2 ratios in combusted isooctane, methanol, and methane were found to be 3.8, 1.25, and 2.0, respectively. The effect of these differences on feedback A/F control with a HEGO (heated exhaust gas oxygen) sensor were also examined. Feedback control of isooctane combustion produced operation very near to stoichiometry. On the other hand, the combustion of methanol under feedback control resulted in steady state lean operation while feedback control of methane combustion produced rich operation. For all three fuels, operation shifted in the lean direction as combustion efficiency was degraded.

This paper describes a study which was carried out to assess the potential for using a gasoline burner to heat the catalytic convertor during cold start. The results showed the catalyst/burner concept to be a promising LEV/ULEV capable technology. On a 1993 Ford Grand Marquis equipped with a catalyst burner system, catalyst light-off was achieved in less than 15 seconds while cold start HC emissions during the first 60 seconds of the FTP test were reduced by 60%. In addition, data are presented which compare the performance of the catalyst/burner to an electrically heated catalyst. In the tests performed, the catalyst/burner system out performed the EHC. Practical considerations, however, such as safety, durability, system integration, and packaging still need to be addressed.

The pulse flame combustor was adapted by researchers at Ford Motor Company in the early 1970s in order to produce exhaust gas simulating the combustion products of the internal combustion engine for the evaluation of automotive catalysts. Over the years, the pulse flame combustor has found application in a wide variety of research oriented tasks associated with automotive catalysts and emissions. More recent research and development efforts which have resulted due to elevated demands toward lower vehicle emission levels have prompted continuing refinements of the apparatus and effected innovative approaches to the study of emerging automotive catalyst and emission control issues with the pulse flame combustor. This report provides an overview of the operation and design evolution of the pulse flame combustor. In addition, recent applications of this laboratory device for studying automotive catalysts, alternative fuels, and other automotive emission control topics are reviewed.