Analytical models for both unlooped and looped Pulsating Heat Pipes (PHPs)
with multiple liquid slugs and vapor plugs are presented in this study. The
governing equations are solved using an explicit finite difference scheme
to predict the behavior of vapor plugs and liquid slugs. The results show t
hat the effect of gravity on the performance of top heat mode unlooped PHP
is insignificant. The effects of diameter, charge ratio, and heating wall t
emperature on the performance of looped and unlooped PHPs are also investig
ated. The results also show that heat transfer in both looped and unlooped
PHPs is due mainly to the exchange of sensible heat.