Project Title:

Sulfur Heat Pipe for 600 Kelvin, Space Heat-Rejection System

10.01-6551A
911195
Sulfur Heat Pipe for 600 Kelvin, Space Heat-Rejection System
Thermacore, Inc.
780 Eden Road
Lancaster
PA
17601
John H.
Rosenfeld
717-569-6551
LeRC
NAS3-26325
204

10.01-6551A
911195

Abstract:

Sulfur Heat Pipe for 600 Kelvin, Space Heat-Rejection System
There is a need for a heat pipe working fluid in the 600 K temperature range for
use in low-mass, heat-rejection radiators for future spacecraft that may include
the SP-100 nuclear reactor space power system. No suitable fluids have been identified.
Sulfur had been rejected for heat pipe service because of excessive viscosity. The
addition of 3-10 percent iodine can reduce the viscosity by three orders of magnitude
to a useful level. This project's objective is the characterization of sulfur-iodine
mixtures as heat pipe fluids. Specific measurements of thermal conductivity and compatibility
with wall and wick materials will be conducted in order to qualify these materials.
Phase II will result in development of full-scale radiator heat pipes using sulfur-iodine
working fluids.
A significant non-governmental market exists in high-temperature, heat-recovery heat
exchangers.
heat pipe, spacecraft radiator, sulfur, working fluid