Investigation on the thermal performance of liquid neon pulsating heat pipes with different bending angles

Cryogenic pulsating heat pipes (PHPs) offer a simple, lightweight, and cost-effective solution for cooling high-temperature superconducting (HTS) magnets, and have the potential to replace high-conductivity metals such as oxygen-free high-conductivity copper. Despite their promise, the influence of geometric constraints, particularly bending angle, on cryogenic PHP performance has not been systematically studied. This work presents the first comprehensive experimental investigation of liquid-neon PHPs with different bending angles (30°, 45°, and 60°) and filling ratios (40–80 %). Results show that a 30° bending angle combined with a 65–70 % filling ratio yields the best thermal performance, supporting stable oscillations and the highest effective heat transport capability. Compared with larger bending angles, this configuration enhances thermal performance and extends the operating heat load range. These findings not only establish a clear design guideline for cryogenic neon PHPs but also provide practical insights for integrating PHPs into next-generation HTS magnet cooling systems.