Gaseous and Particulate Matter Emissions of a Supercharged Spark Ignited Hydrogen Fueled Internal Combustion Engine

A spark ignited hydrogen fueled engine was operated at three equivalence ratios (0.4, 0.5, and 0.6) with a supercharger. During steady-state road load conditions, the engine produced exceptionally low unburned hydrocarbon, carbon monoxide, carbon dioxide, and particulate matter emissions. The oxides of nitrogen (NOx) emissions of the supercharged engine were 31.4, 149.5, and 787.0 mg*NOx/km for the equivalence ratios 0.4, 0.5, and 0.6 respectively. Given that the current EPA regulations are 99.4 mg*NOx/km, this engine configuration represents a possible replacement option for gasoline fueled engines without the need for exhaust aftertreatment. During engine start-up, some of the supercharged tests exhibited particulate matter emission spikes. These particulate matter spikes do not seem to be related to equivalence ratio, coolant temperature, testing order, or start-up acceleration. Currently, there is no explanation why some of the tests produced particulate matter during engine start-up and others did not.M.A.S