The heat pipe has been regarded as one of the most
efficient heat transfer devices. The two-phase
closed thermosyphon (TPCT) is a gravity assisted
wickless heat pipe, which returns the condensate
from the condenser section to the evaporator
section under the effect of the gravity (Madam,
1983, Zhang, 2003). a two-phase closed
thermosyphon consists of three sections:
evaporator section, adiabatic section and condenser
section, as shown in Fig. 1