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Loop Heat Pipes (LHPs) are being considered for cooling of military combat vehicles and spinning spacecraft. In these applications, it is important to understand the effect of an accelerating force on the performance of LHPs. In order to investigate such an effect, a miniature LHP was installed on a spin table and subjected to variable accelerating forces by spinning the table at different angular speeds. Several patterns of accelerating forces were applied, i.e. continuous spin at different speeds and periodic spin at different speeds and frequencies. The resulting centrifugal accelerations ranged from 1.2 g's to 4.8 g's. This paper presents the second part of the experimental study, i.e. the effect of an accelerating force on the LHP operating temperature. It has been known that the LHP operating temperature under a stationary condition is a function of the evaporator power and the condenser sink temperature when the compensation temperature is not actively controlled.

Loop Heat Pipes (LHPs) are being considered for cooling of military combat vehicles and spinning spacecraft. In these applications, it is important to understand the effect of an accelerating force on the performance of LHPs. In order to investigate such an effect, a miniature LHP was installed on a spin table and subjected to variable accelerating forces by spinning the table at different angular speeds. Several patterns of accelerating forces were applied, i.e. continuous spin at different speeds and periodic spin at different speeds and frequencies. The resulting centrifugal accelerations ranged from 1.2 g's to 4.8 g's. This paper presents the first part of the experimental study, i.e. the effects of an accelerating force on the LHP start-up. Tests were conducted by varying the heat load to the evaporator, condenser sink temperature, and LHP orientation relative to the direction of the accelerating force.