Currently, SuperCritical Fluids (SFCs) are used in various
industries worldwide. The largest application of SCFs is the use
of SuperCritical Water (SCW) at SuperCritical Pressure (SCP)
coal-fired power plants. Using SCP Rankine “steam” cycle
allows to reach gross thermal efficiencies of a plant up to 55%.
On contrary, current subcritical-pressure water-cooled Nuclear
Power Plants (NPPs) of Generations II and III have significantly
lower gross thermal efficiencies within the range of 30 - 36% (up
to 37 - 38% for Generation III+ nuclear-power reactors).
To increase efficiency of next generation – Generation IV
NPPs higher parameters (mainly temperature) should be reached
for reactors’ coolants and corresponding to that for power cycles.
Analysis of Generation IV nuclear-reactor concepts shows that
three concepts will be cooled with SCFs such as helium and
water, and there is a possibility that other concepts will be linked
to SCP Rankine cycle or to SCP Brayton cycle with helium or
carbon dioxide working fluids.
Therefore, specifics of thermophysical properties and heat
transfer of SCFs are very important for reliability and safety of
new thermal and nuclear power plants. Also, for SCW nuclear
reactors heat transfer to SCW flowing inside various bundle
geometries has to be understood and estimated.
Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016.