• experimental
• flow pattern
• pulsating heat pipe
• start-up

Pulsating heat pipes (PHPs) are passive two-phase heat transfer devices with great potential as thermal control system components for space application. They are also lightweight, very flexible in terms of applicability and have high heat transfer capability. Despite their many positive aspects, especially if compared with the traditional heat pipes, the industry is reluctant to dive in PHPs production due to their low TRL. The current thesis is a report of the work carried out on a multi parametric experimental device developed by Pisa university and financed by the US air force research laboratory. After a detailed description of the experimental device and the tests procedure; the main focuses of the investigation are (1) the relation between start-up time and pulsating heat pipes initial conditions and (2) a qualitative flow pattern map analyzing the flow regimes established by two phase flow for varying parameters.