Speaker
Description
In fusion reactors, the durability of plasma-facing components (PFCs) is heavily compromised by the impacts of high-velocity tungsten (W) dust, particularly during extreme events such as runaway electron terminations. These incidents can propel dust particles at velocities reaching several kilometers per second, leading to significant material erosion and structural damage. While existing models primarily focus on low-velocity impacts, there remains a critical knowledge gap concerning high-velocity impacts, which is essential for the development of reactors like ITER and DEMO.
To address this gap, our study utilizes large-scale molecular dynamics simulations to explore the effects of high-velocity W dust impacts on tungsten walls under extreme operational conditions. The simulations cover a wide range of impact velocities (2.5 to 4.5 km/s), angles (0° to 75°), and temperatures (300 to 3000 K). By incorporating up to 300 million atoms, these simulations provide a detailed analysis of how impact angle and temperature influence crater morphology and ejecta distribution.
Our findings reveal that both the angle of impact and the operational temperature significantly affect the resulting crater structures and the dynamics of material ejection. The study delves into sputtering processes, material degradation, and deformation mechanisms at the atomic level, offering critical insights into the behavior of tungsten walls under high-velocity impacts.
This research substantially enhances our understanding of dust-wall interactions in fusion environments, contributing to the development of more resilient materials for future fusion energy systems. The insights gained from this work will aid in improving the durability and operational efficiency of PFCs, which are crucial for the successful deployment of next-generation fusion reactors.
