Modern heavy-duty and medium-duty compression ignition engines are relatively efficient and power dense but still suffer from relatively high criteria pollutant and greenhouse gas emissions. Furthermore, the suite of exhaust after-treatment devices required to meet the current criteria pollutant emissions standards is both complicated and expensive. In some cases the after- treatment system cost rivals the cost of the engine. An opportunity exists, through the co- optimization of fuels and engines, to reduce the criteria pollutant emissions, greenhouse gas emissions, and system cost and complexity, all while significantly increasing the engine thermal efficiency. Supercritical reforming of wet bio-ethanol is proposed as a method to greatly reduce the greenhouse gas emissions and criteria pollutant emissions of heavy-duty and medium-duty compression ignition engines while simultaneously improving the engine thermal efficiency and reducing the fuel production cost and carbon intensity. Computer modeling of the reformer and engine system will be used to develop an improved understanding of the system tradeoffs and potential benefits. System layout and requirements will be developed in preparation for next phase experimental efforts. A modeling methodology including computational fluid dynamics, one-dimensional cycle simulations, and chemistry calculations will be used. The resulting technology will reduce the criteria and greenhouse gas emissions, initial engine plus after-treatment system costs, and also reduce ongoing fuel and maintenance costs, which results in an economic benefit. Compression-ignition engines are the workhorses of the modern economy and touch virtually every sector of the economy in both the private and public sectors. The technology also enables the use low carbon impact bio-fuels. This proposal is focused on the use of wet bio-ethanol in compression-ignition engines for on-road transportation, however the basic technology can also be applied to virtually any liquid fuel. Conventional fossil fuels could be used, including fuels that are not currently suitable for use in compression-ignition engines, e.g., gasoline, methanol, JP-8.
