(246e) Measurements of the Thermal Conductivity of Dodecane- N2 Mixtures at Temperatures up to 700 K and Pressures up to 70 Mpa

The engine combustion network (ECN) uses dodecane as the fuel of choice for the "Spray A" and "Spray B" operating conditions which are used widely in both experimental and computational fluid dynamics investigations of diesel sprays. In non-reactive spray experiments nitrogen (as a surrogate for air) is used as the ambient gas in the chamber to study spray break-up experimentally and with computational fluid dynamics. Transport properties are critical in assessing the heat and mass transfer processes that occur in the combustion chamber following fuel injection. However, to date no transport property data (viscosity, thermal conductivity, and diffusion coefficient) exist for any fuel-nitrogen mixtures. Therefore, this study reports original thermal conductivity data for asymmetric n-dodecane-N₂ mixtures, measured using a single-wire, transient hot-wire apparatus at temperatures ranging from 300 K to 700 K and pressures from the bubble point to 70 MPa. Mixture preparation and loading techniques for this highly asymmetric mixture and detailed uncertainty analysis are discussed. Additionally, corrections for absorption/emissions thermal radiation are identified which are more prevalent at the high temperatures encountered in this study. The new data are compared to existing extended corresponding states models implemented in REFPROP.