Ethanol reformer for on-board octane control in spark ignition engines

University of Minnesota/William Northrop

In this preliminary investigative project, the University of Minnesota team led by Prof. Will Northrop will design and construct a small reactor for partially reforming ethanol and ethanol blends at high thermal efficiency. The design is based on fundamental research that the PI has done under an NSF grant entitled, “High Equivalence Ratio Partial Oxidation of Liquid Fuels by Reactive Volatilization”. In the prior research, we have investigated the use of non-premixed short contact time reactor architectures for partially reforming liquid fuels1. The reactor to be constructed in the proposed work is depicted in Figure 1. In the reactor, air is sent through a porous catalytic substrate coated with reforming catalyst. Initially the air is preheated to allow reactions to begin. Once lit, the heating element will no longer be needed to sustain the reforming reactions. Fuel is atomized and sprayed directly onto the opposite side of the hot catalyst. The two react at short contact time and ethanol is partially converted to reformed gas species like hydrogen, methane and carbon monoxide. The gas mixture can than be sent to the intake of a SI engine to alter ignition properties of the fuel. Altering ignition properties is one strategy for enabling advanced low temperature combustion modes in engines. Ethanol is an ideal fuel for reforming as it decomposes at a lower temperature than gasoline on typical reforming catalysts and has a low sooting tendency in low oxygen environments. The reforming reactor will be bench tested and simulated using computer software in this research project.