Development and manufacture of visual miniature loop heat pipe

An innovative visual miniature loop heat pipe (mLHP) was manufactured using mechanical machining technique, material processing and thermal science. Components fabrication involves the production of compensation chamber (CC), evaporator, working fluid transport lines, condenser and capillary porous wick. A pressing mould was made in advance and the cold pressing sintering method was adopted to make the nickel wick. The wick porosity is 60% and effective pore radius is 5 εm measured by Scanning Electron Microscopy (SEM). The condenser was made of Acrylic glass to achieve the purpose of visualization. A novel transition joining method solved the problem of seal between glass and metal. To some extent, this fabrication process actualizes the visual research of the mLHP and provides a method to investigate the operational mechanism of mLHP.