Test Results for a High Power Thermal Management System 2008-01-1997

In response to the identified needs of emerging high power spacecraft applications, a multiple evaporator Hybrid Loop Heat Pipe (H-LHP) was developed and tested as part of a Dual Use Science and Technology (DUS&T) program co-sponsored by ATK and AFRL/PRP. During the course of the DUS&T program, a two-kilowatt system with three evaporators was developed and tested to identify viable system architectures and characterize system performance capabilities as a function of heat load profiles and spatial distribution of the evaporators. Following the successful development of the two-kilowatt system, a 10-kilowatt system with six evaporators was fabricated and tested. Tests were performed with the system operating in a totally passive, capillary-pumped mode, where applying a small amount of power to a sweepage evaporator provides the auxiliary flow through the primary evaporators, and as a self-regulating, capillary-controlled mechanically pumped system. This paper will provide a description of the 10-kilowatt multi-evaporator system and present the results of the passive and mechanically pump test programs.