Flat thermosyphon-based heat sink
A novel flat thermosyphon-based heat sink is developed for cooling electronic chips. The heat sink comprises a boiling plate and hollow fin condensing structure. The boiling plate and the condensing structure form a chamber where the working fluid is filled. The heat source in contact with the boiling plate boils the working fluid on the boiling plate. The vapor bubbles travel up due to the buoyancy force, and the generated vapor gets condensed inside the hollow fin condensing structure. The condensed liquid falls back into the liquid pool because of the gravity force. The boiling-condensation cycle repeats, and the heat is transferred from the heat source to the fin arrays coupled with ambient air. The thermal performance of the heat sink is being improved further through minichannels on the boiling plate and superhydrophobic coating on the hollow fin condenser surface. The in-house experimental setup for testing the flat thermosyphon based heat sink is shown in the figure.
Flat Plate Pulsating Heat Pipe
Studies on FPPHP are being explored for cooling electronic chips. The FPPHP comprises a copper plate with minichannels forming a closed loop in which the working fluid is filled. The heat source and the cooler block in contact with the FPPHP boils and condenses the working fluid, respectively. The pressure difference between the evaporator and condenser sections oscillates the liquid-vapor slug-plugs in the capillary minichannels. The heat is transferred passively from the heat source to the heat sink. The thermal performance of the FPPHP is being improved further through surface wettability modifications and binary mixtures. In addition, the flow patterns inside the FPPHP are studied through high-speed imaging to get insights into the heat transfer mechanisms. The in-house experimental setup for testing the FPPHP is shown in the figure.