Search Results

Changan has upgraded its 1.6 L naturally aspirated GDI engine to meet future fuel economy and emission regulation base on its previous 1.6 L naturally aspirated GDI engine, the major upgrades include a high compression ratio of 13, 35Mpa direct injection system, cooled external EGR, thermo management module,and extensive measures to reduce friction. With this new engine, the vehicle fuel consumption is reduced by 9%, and meet the China 6b emission standard without GPF.

Due to its load control strategy via fresh charge quantity, pumping loss in a homogenous charge gasoline engine is a significant contributor to the high fuel consumption rate at light load. Exhaust gas recirculation (EGR) and lean burn technologies are the common means to reduce gasoline engine pumping loss for fuel economy improvement. Many previous publications compared the EGR and lean burn concepts. However, few of those were able to compare the EGR and lean burn concepts under the same in-cylinder dilution basis. Usually the un-swept in-cylinder residual gas fraction (RGF), which can be significant at very low loads, was ignored due to lack of appropriate method to determine it. Also the theoretical potential and practical limitations were rarely discussed. In this paper, a Naturally Aspirated (NA) gasoline engine was systematically tested for both the EGR and lean mixture concepts on an engine dyno. under the same speed and load conditions.