High Efficiency and Clean Diesel Combustion Using Double Premixed Ignition (Third Report)

- Study on the Emissions and Noise Reduction by the Second Injection -

Abstract

In the previous papers, a combustion system which reduces emissions, noise and fuel consumption using premixed charge compression ignition (PCCI) with split injection of fuel was reported. The keys of this combustion system are the timing and amount of the second injection. In this paper, in-cylinder visualizations and numerical simulations showed that the oxidation of rich flame is accelerated and the soot formation in the near nozzle region is inhibited under the best second injection timing condition with an adequate injection interval. Combustion noise spectra analysis found that a noise canceling occurs between two peaks of pressure rise rate.