著者
橋詰 剛 宮本 武司 赤川 久 辻村 欽司
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 B編 (ISSN:03875016)
巻号頁・発行日
vol.66, no.641, pp.286-293, 2000-01-25 (Released:2008-03-28)
参考文献数
15
被引用文献数
2 1

By injecting fuel at the very early stage of compression stroke and thus creating homogeneous lean mixture before ignition, (PREDIC;PREmixed lean DIesel Combustion), simultaneous reduction of NOx and smoke was obtained. However, since increasing the mixture equivalence ratio cause knocking, it was difficult to operate at higher load conditions. In this study, in order to reduce combustion rate at high load conditions in a premixed compression ignition engine, multiple stage injection method and EGR were combined, and heterogeneous mixture was made before ignition. The engine test results showed that NOx emissions could be reduced to less than 50 ppm, without knocking even at full load conditions. In addition, smoke emissions were also maintained below invisible level. It can be understood that the premixing of fuel was advanced, smoke was reduced, and EGR rate was increased, resulting lower heat release rate and NOx emissions.
著者
橋詰 剛 宮本 武司 赤川 久 辻村 欽司
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 B編 (ISSN:03875016)
巻号頁・発行日
vol.66, no.652, pp.3233-3240, 2000-12-25 (Released:2008-03-28)
参考文献数
13

Simultaneous reduction of NOχ and smoke under high load conditions could be obtained by MULDIC(MULtiple stage DIesel Combustion) where mixture was made stratified before ignition. In this investigation of the basic characteristics of MULDIC, gaseous fuels (DME, Propane) were charged into the intake air which led to the creation of homogeneous lean mixture, and liquid fuel was injected into the cylinder and made rich mixture. The results of the engine test showed that NOχ emissions could be reduced to less than 100 ppm and smoke emissions were also maintained 0 FSN even at higher loads. Moreover, homogeneous rich mixture test results showed that low smoke combustion could be obtained under equivalence ratio of 1.6. In MULDIC, increasing the ignition delay period of injected fuel, soot formation rate was decreased, because over rich region was avoided.