Correlation of Hydrogen Heat Transfer in Boiling and Supercritical Pressure States

Abstract

The use of hydrogen as a working fluid in both chemical and nuclear propulsion systems necessitates convective heat transfer information over a broad range of fluid states. Current heat transfer correlation schemes available in the literature are discussed in terms of their applicability to hydrogen heat transfer. Similarities in the subcritical and supercritical (pressure) heat transfer mechanisms and associated experimental data are reported. Summarized are correlation schemes formulated from heated tube data which apply to: 1) film boiling of liquid hydrogen; 2) hydrogen at supercritical pressure just above and below critical temperature; and 3) low temperature hydrogen (150 to 250 deg R) above the critical pressure. Parts 1 and 2 have required correlation schemes that depart from the conventional convective pipe flow concepts. It does appear that the conventional pipe flow heat transfer theory can be applied to part 3. (auth)