Simultaneous Reduction of NO_x and Soot in Diesel Engines Using a New Mixture Preparation Method

Abstract

We describe an experimental study on the simultaneous reduction of NO_x and soot in diesel engines achieved using a new mixture preparation method. To produce a lean uniform mixture, a new type of injection equipment was used with various injection timings. Between the late and very early injection timings, there was an injection timing range at which the amount of NO_x produced was extremely low and soot was not emitted. NO_x production was suppressed to a level one hundredth that of conventional DI diesel engines. However, with increasing load, NO_x production increased sharply and strong diesel knocking occurred. This indicated that NO_x production was strongly influenced by the process of mixture formation.