Abstract
For direct-injection gasoline engines, reducing fuel consumption and particulate number in exhaust gas are needed. Reducing particulate number can be achieved by reducing the fuel adhesion to a cylinder and piston surface, and by injecting fuel multiple times which increases homogeneity degree of fuel-air mixture. For this purpose, reducing the minimum injection quantity is required. We developed the simulator which can analyze behavior of the valve and the injection characteristics, by taking a non-steady electromagnetic field analysis and the flow analysis in an equation of motion, and taking into account of the detailed of structure of the injector. We clarified that the valve bouncing during the opening action and residual magnetic force causes an increase of the minimum injection quantity.
