Modelling CO2 conversion by dry reforming in a piston engine

We investigate the feasibility of a piston engine for a simultaneous use as a heat engine and a dry reformer, i.e., as a chemical converter which transforms a CO$_\text{2}$/CH$_\text{4}$ mixture to syngas (H$_\text{2}$/CO). This process is relevant because it can allow a conventional heat engine to operate on a standard fossil fuel while removing CO$_\text{2}$. Previous experimental work in a Rapid Compression Machine (RCM) showed that dry reforming in piston-compressors with CO$_\text{2}$ conversion levels of up to 50% can readily be performed. Analysis of these results indicates that higher conversion, combined with production of work, should be possible. The corresponding operation conditions, however, are hard to assess experimentally. In this work, we evaluate the potential of combined dry reforming and work generation in a piston engine by numerical simulations. A large ensemble of numerical simulations is performed, each with varied initial conditions, and the resulting CO$_\text{2}$ conversion and work output for each ensemble member are recorded. The resulting conversion / work output maps are used to identify conditions under which a combined heat engine/dry reforming device can operate efficiently. ... mehrA key in this approach is an efficient search in the high-dimensional space of initial conditions. The results from a “straight-forward” random search are compared to results obtained by a genetic search algorithm.