Date of Award


Document Type


Degree Name

Master of Science in Astronautical Engineering


Department of Aeronautics and Astronautics


An experimental investigation was performed to determine the effects of transverse vibrations on the performance of an ammonia-aluminum axial groove wick heat pipe. Theoretical calculations predicted a performance degradation due to the working fluid being shaken out of the upper capillary grooves. A benchtop shaker was used to apply transverse, sinusoidal vibrations of 30, 35, and 40 Hertz, corresponding to peak acceleration amplitudes of 1.84g, 2.50g, and 3.27g, respectively. Maximum heat throughput, Q sub max, of the vibrating heat pipe was measured. A comparison of these values and static Q sub max values indicated a degradation in heat pipe performance. A mean performance deterioration of 27.6 Watts was measured for the 1 .84g case; an average degradation of 12.9 percent from static heat pipe performance. At 2.50g peak acceleration, the degradation rose to 37.3 Watts; an average decrease of 14.8 percent from static performance. An average deterioration in performance of 28.1 percent was recorded for the 3.27g case. This amounted to a mean performance degradation of 69.3 Watts. The results of this investigation revealed that transverse, sinusoidal vibrations have a detrimental impact on the performance of an ammonia-axial groove wick heat pipe. Further, the performance degradation increases with increasing vibrational peak acceleration amplitude.

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