• wavelet analysis
• pulsating heat pipe
• pressure signal
• time-frequency analysis

Thermal control is a fundamental problem in spacecraft design, since a
space mission can fail catastrophically due to inadequate heat management.
To address heating issues, past work has given sharp attention to the Pulsating
Heat Pipe (PHP), a special kind of wickless heat pipe which is characterized
by oscillating/pulsating thermally induced
ow motion. The operation PHPs
are intrinsically unsteady, and therefore they need further investigation for the
development of reliable heat transfer models and robust design tools.
This thesis examines an operating PHP with the goal of understanding how
the amplitude and the frequencies of its oscillations vary, depending on the
pulsating heat pipe parameters. We describe the post-processing of the data
collected from a hybrid Pulsating Heat Pipe in microgravity conditions and
with varying heat load input. Through a wavelet analysis, we show that
the PHP oscillation frequency increases with increasing heat load input, as
experted from theoretical/phisical considerations.