Study of a Fuel Supply Pump With a Piezoelectric Effect for Micro Solid Oxide Fuel Cells

Abstract

A novel design for an ethanol injection system has been proposed, which consists of the fuel injector, two valves, one pump chamber, and one piezoelectric device (central vibration). The system uses a micro-diaphragm pump with a piezoelectric device for the micro solid oxide fuel cells (SOFC), which operate at a low temperature (550 to 600 °C) and are supplied by Enerage Inc. The diameters of the pump chamber are 31 mm and 23mm, and the depths of the chamber are 1 mm and 2 mm. When the piezoelectric device actuates for changing pump chamber volume, the valves will be opened/closed, and the ethanol will be delivered into SOFC system due to its pressure variation. The dimensions of the injector chamber, vibration frequencies of piezoelectric (PZT) device, input voltages, and valve thickness and shape, are used as important parameters for the performance of the novel ethanol injection system. The experimental results show that the ethanol flow rate can reach 170ml/min at a piezoelectric device frequency of 75Hz. In addition, the ethanol flow rate is higher than the water flow rate.