A Study of Forced Convection Heat Transfer to Supercritical Hydrogen

Hydrogen heat-transfer data in the supercritical region has been compared with an analysis based on fully developed turbulent pipe flow with variable fluid properties. The comparison indicated an additional variable property effect not included in the analysis. However, this approach led to the correlation of the data over the full range of experimental conditions. These results indicate that the mechanism of supercritical heat transfer with hydrogen can be explained on the basis of variable fluid property effects without postulating a new mechanism for heat transfer, as done in previous investigations. It was also found that the pipe flow equation with fluid properties based on the film temperature can be made to correlate the data by correcting the calculated values with a simple function of wall to bulk kinematic viscosity ratio. This method provides a rapid means for determining supercritical hydrogen heat transfer with accuracy sufficient for most purposes.