Mems Mass Flow Controller for Liquid Fuel Supply to HCCI-Driven Engine

In this paper, a second generation MEMS mass flow controller (MFC) for liquid fuel delivery to a miniaturized homogeneous charge compression ignition (HCCI) engine is presented. In contrast to the first generation MFC [1], it has a highly improved on/off-characteristic and fuel delivery range. This is achieved by a complete redesign of the valve cap and package, minimizing particles in the fuel outlet and package stress. Various fuels (and water) are calibrated, for instance, ethanol and water with maximum mass flow rates of 15 g/min and 20 g/min, respectively (at 100 kPa inlet pressure). The on/off-ratio with water is nearly 3300:1 (at 100 kPa inlet pressure). The maximum power consumption during continuous operation is 50 µW.