The project investigates the operational limits of Pulsating Heat Pipes (PHPs), a promising passive heat transfer technology characterized by simplicity, compactness, and high thermal performance. Despite their potential, PHPs are not yet widely adopted due to unclear operational boundaries and inconsistent experimental data. This project developed an innovative, modular test rig capable of varying multiple parameters (e.g., number of heating/cooling sections, condenser temperature, filling ratio) to systematically study PHP behavior. Using ethanol as the working fluid, experiments were conducted on configurations with 5, 7, and 11 evaporator sections. The study focused on startup behavior, steady-state performance, and the influence of initial fluid distribution. A novel startup time identification algorithm was developed, and the CASCO simulation tool was validated against experimental data. Results show that PHP activation and stability depend not only on geometry but also on the interplay between heat input and condenser temperature. The findings contribute to a deeper understanding of PHP thermofluidic behavior, offering valuable insights for future design and modeling efforts.
Coordinator: University of Pisa (Unipi)
Start date: March 2020
End date: December 2023
Duration: 46 months
Call title: AFRL/EOARD Research Collaboration Program
Unipi role: Project Lead and Experimental Research Partner
Website:https://community.apan.org/wg/afosr/w/researcha…
