Application of HLWP supercritical light water properties in CATHENA

The HLWP (Heavy and Light Water Properties) library provides a computationally efficient means to accurately produce the thermodynamic and thermophysical properties of heavy and light water and the gas properties of air, nitrogen, helium, argon, hydrogen, and carbon dioxide. The light water routines have been updated to provide properties at supercritical pressures for the design of potential future generations of CANDU reactors. The HLWP routines are currently included in a variety of thermalhydraulic programs (CATHENA, ASSERT, TUBRUPT-IST, TEP), and are being considered for inclusion in others (GOTHIC, NUCIRC). The current work describes the accuracy and limitations of the newly developed supercritical routines. Sample results are presented to demonstrate their use in thermalhydraulic calculations and a prototype version of CATHENA. (author)