Dynamometer testing of an ethanol-water fueled transit van

Abstract

Previous research using catalytic igniters and ethanol water fueled mixtures has shown potential for lowering CO and NO x emissions while increasing engine efficiency over conventional -engine configurations. Catalytic ignition systems allow combustion initiation over a much wider range of stoichiometry and water composition than traditional spark ignition systems. The platform explored in this research is a transit van converted to operate on either gasoline or ethanol water fuel mixtures. Special attention was devoted to improve cold starting and installing additional on board sensors and equipment for future testing. System features include integration of a wide band oxygen sensor, state-of-the-art engine management system, exhaust gas temperature sampling using platinum thin film resistive temperature devices and variable voltage control of catalytic igniters using DC-DC boost converters. The platform explored in this research is a transit van converted to operate on either gasoline or ethanol water fuel mixtures. Special attention was devoted to improve cold starting and installing additional on board sensors and equipment for future testing. System features include integration of a wide band oxygen sensor, state-of-the-art engine management system, exhaust gas temperature sampling using platinum thin film resistive temperature devices, and variable voltage control of catalytic igniters using DC-DC boost converters. Extensive engine performance and emissions testing for 70% ethanol 30% water fuel mixtures operating at air to fuel ratios (AFR) of = 1 and = 1.15 have shown a substantial reduction in NOx and CO emissions without the use of exhaust after treatment compared to gasoline emissions. Lean mixtures also show reduced emissions and increased thermal efficiency compared to stoichiometric conditions. Chassis dynamometer tests comparing thermal efficiency, and brake specific emissions of NOx, CO 2 , CO, and hydrocarbons for the ethanol-water fuel mixtures over a wide range of operating conditions are shown.