Two-phase closed vertical thermosyphons (TCVT), also known as gravity-assisted heat pipes, are very efficient heat transfer devices. They work in two-phase close cycles where latent heat of evaporation and condensation is used to transfer heat, and are widely employed in industry applications. The increasing number of thermally efficient equipment that apply TCVT are explained by their high geometric flexibility and low cost, being important solutions for heat transfer and temperature control problems.

This research presents a brief guide on the design, prototyping, and experimental testing of two-phase closed vertical thermosyphons (TCVT). The work was conducted at LEPTEN/Labtucal, a research laboratory in Brazil focused on applied heat transfer fields, which includes heat pipe and thermosyphon technology development. The design and prototyping guidelines of a TCVT are described in details. All the prototyping and testing of the system is conducted according to procedures presented in up-to-date literature, using proper equipment and following the steps previously established by other researchers. The experimental setup and methods to evaluate the designed TCVT performance are presented. Experimental results for two fluids (namely R141b and acetone) using different filling ratios are showed in order to obtain the percentage of fluid that yields the minimum temperature difference along the thermosyphon. Results are discussed and further analyzed to conclude the configuration that achieves best performance.