Speaker
Paul Humrickhouse
(Fusion Safety Program)
Description
Thermal hydraulic and accident analysis codes such as RELAP5-3D and MELCOR rely on an equation of state to specify all the thermodynamic properties of fusion-relevant working fluids such as PbLi. The existing liquid metal fluid properties in both RELAP5-3D and MELCOR are based on a five parameter "soft sphere" equation of state for which parameter sets that approximately reproduce experiment data were available in the literature. The PbLi parameters were based on a linear, mass-weighted average of the parameters for pure Pb and pure Li, which does not always result in adequate agreement between the equation and experimental data for PbLi, much of which was not available at the time the original equations were implemented. In order to address this shortcoming, we describe here a modification and non-linear least squares fitting of the parameters to closely match available experiment data for the density, sound speed, and specific heat capacity of liquid PbLi over a range of temperatures. The new equation has been implemented in both RELAP5-3D and MELCOR, and we make comparisons with both codes to experiment data to verify the implementation. Transport properties such as the thermal conductivity and viscosity, though not derived from the equation of state, have also been updated.
Co-authors
Brad Merrill
(Fusion Safety Program, Idaho National Laboratory, Idaho Falls, United States)
Paul Humrickhouse
(Fusion Safety Program, Idaho National Laboratory, Idaho Falls, United States)
