Silicon Carbide (SiC) Device and Module Reliability, Performance of a Loop Heat Pipe Subjected to a Phase-Coupled Heat Input to an Acceleration Field
Technical Report,01 Oct 2014,30 Jan 2016
Flight Systems Integration Branch, Power and Control Division Wright-Patterson Air Force Base United States
Pagination or Media Count:
The objective of this research was to experimentally investigate transient operating characteristics of a titanium-water loop heat pipe subjected to a phase-coupled heat input and acceleration field. The acceleration field was generated using a centrifuge table by varying the radial acceleration. Both evaporator heat input and radial acceleration were generated as periodic sine functions at a frequency, f 0.05 Hz. Evaporator heat input and radial acceleration peak-to-peak values varied from 100 W Qin 700 W and 3.0 g ar 10 g, respectively. The radial acceleration sine function was initiated either at the same time as the evaporator heat input function or delayed resulting in varying phase angles, PSI 0, 180, and 270 C. The inlet condenser cold plate coolant temperature were varied at Tcp 45 C, 50 C, and 60 C. The rejected heat from the condenser was measured over time and compared to a first-order thermal system. It was found that energy was dissipated in the condenser as a second-order phenomena and varied with phase evaporator heat input and acceleration field phase angle and condenser input temperature. The equivalent time constant tended to decrease with increasing phase angle and decreasing condenser inlet temperature while the delay time increased with increasing phase angle and decreasing condenser inlet temperature.