HEAT TRANSFER IN LOW PRESSURE LITHIUM CONDENSATION

Abstract

This paper presents the results of an experimental investigation into lithium condensation. The objective of the investigation is to find the condensing side heat transfer coefficients of lithium on the vertical flow configuration and to explain the discrepancy between Nusselt's theory and the experimental results. The heat fluxes in these experiments varied from about 1.3 × 10⁴ W/m² at 833 k to 1.3 × 10⁵ W/m2 at 898 k, giving heat transfer coefficients of 4078 W/m² k to 37805 W/m² k. These values appear 0.3% to 3% of those predicted by the Nusselt theory. Condensate film thickness was calculated by the Nusselt theory. Boiling and condensing of lithium at low, less than atmospheric pressure, appears to be an efficient energy transport mechanism that may find use in space applications or cooling of the first wall in fusion reactors.

KEYWORDS:

• Lithium condensation
• Heat transfer