Visualization of Loop Heat Pipe with Multiple Evaporators under Microgravity

In this paper, a loop heat pipe with multiple evaporators (MLHP) whose evaporators and a condenser can be visualized was newly designed, fabricated. The inside of a wick core and a compensation chamber were observed by using borescopes. Flow pattern and a length of two-phase region of the condenser were observed by using a transparent tube. The both side heat load test, and one side heat load test were carried out under μG environment by parabolic flight. The temperature and pressure change of these experiment were measured. The visualization of MLHP was also conducted under 1G and μG environment. The vapor- liquid distribution was also observed under 1G and μG environment, and the change of the condense style of the condenser between 1G and μG was confirmed. The heat leak is also calculated by a new evaporator-CC model which considers the vapor-liquid distribution in the CC.