Loop Heat Pipe Startup Behaviors

Date

2016-07-10

Journal Title

Journal ISSN

Volume Title

Publisher

46th International Conference on Environmental Systems

Abstract

A loop heat pipe must start successfully before it can commence its service. The startup transient represents one of the most complex phenomena in the loop heat pipe operation. This paper discusses various aspects of loop heat pipe startup behaviors. Topics include the four startup scenarios, the initial fluid distribution between the evaporator and reservoir that determines the startup scenario, factors that affect the fluid distribution between the evaporator and reservoir, difficulties encountered during the low power startup, and methods to enhance the startup success. Also addressed are the thermodynamic constraint between the evaporator and reservoir in the loop heat pipe operation, the superheat requirement for nucleate boiling, pressure spike and pressure surge during the startup transient, and repeated cycles of loop startup and shutdown under certain conditions.

Description

United States
NASA GSFC
201
ICES201: Two-Phase Thermal Control Technology
Vienna, Austria
Jentung Ku, NASA Goddard Space Flight Center, USA
The 46th International Conference on Environmental Systems was held in Vienna, Austria, USA on 10 July 2016 through 14 July 2016.

Keywords

two-phase heat transfer, loop heat pipes, spacecraft thermal control

Citation