Characterization of a high capacity, dual compensation chamber loop heat pipe

Results of acceptance tests at the Institute of Thermal Physics (ITP) in Russia and initial performance tests at the Air Force Research Laboratory (AFRL) of a dual compensation chamber (CC) loop heat pipe (LHP) are compared for three orientations. At steady state, temperatures were higher and heat transfer coefficients and conductance were lower at AFRL. These differences are attributed to higher resistance due to usage, rather than test, mounting and more complex insulation lay-up at AFRL. For the horizontal orientation power (W) and heat flux (W /cm2) reached at IPT and AFRL were 1500 and 10.5, and 900 and 6.3, respectively. AFRL transient data showed brief reverse flow on startup for some runs with power at or below 50 W, at times marked temperature fluctuations, and response to chiller temperature change.