Experimental Determination of Local H/C Ratio and Hydrogen-Particulate

An intermittent sampling valve was used to investigate local fuel H/C ratio and species concentrations in an operating DI diesel engine. Additionally, predictions of carbon and hydrogen originating from particulates and nonmethane hydrocarbons (carbon and hydrogen remainders) were made by calculation. Sample H/C ratio was used to assess local fuel phase as gaseous or liquid.

Evidence of intermediate species quenching in the lean region between spray plumes was found under low swirl. Reduction in the rate of penetration under high swirl may account for the observed loss in efficiency under this condition.