Heat transfer and pressure drop in forced convection to fluids at supercritical pressures

A new concept in thermal engineering optimization : the pericritical cycle with multi-heating and its application to concentrating solar power

“…The abrupt change of thermo-physical properties in heated supercritical fluids in the vicinity of the pseudo-critical point results in a specific behavior of flow and heat transfer. This behavior is very similar to the boiling occurring at subcritical pressures (Pioro, 2016). When a supercritical fluid with a bulk temperature below the pseudocritical temperature is heated, some layers near the heating surface may reach temperatures above the pseudocritical temperature.…”

“…The density difference will move the gaseous volume from the heating surface to the inside of the tube. This phenomena, called boiling when the pressure is below the critical pressure and pseudo-boiling when it is above (Pioro, 2016), has specific features that Gnielinski correlation cannot predict. The correlation has more difficulties to predict the heat transfer coefficient at the beginning of heating.…”