Nonlinear structure of the diffusing gas-metal interface in a thermonuclear plasma.

Area of Science:

• Plasma Physics
• Fluid Dynamics
• Materials Science

Background:

• Understanding plasma diffusion layers is crucial for various applications, including fusion energy and materials processing.
• The dynamics of gas-metal interfaces under diffusion are complex and not fully understood.

Purpose of the Study:

• To theoretically describe the structure and dynamics of a plasma diffusion layer forming at a gas-metal interface.
• To investigate the role of mass diffusion in layer development under isothermal and isobaric conditions.

Main Methods:

• Theoretical modeling of the plasma diffusion layer.
• Analysis of layer dynamics focusing on mass diffusion processes.
• Development and verification of similarity solutions using ion kinetic code simulations.

Main Results:

• The plasma diffusion layer exhibits asymmetric and highly nonlinear features.
• A sharp boundary, termed a 'front,' is identified on the gas side due to near-zero diffusion.
• Similarity solutions for nonlinear profiles were successfully found and validated.

Conclusions:

• The developed theoretical structure accurately describes plasma diffusion layer formation.
• The identified 'front' phenomenon has implications for understanding boundary interactions.
• A criterion is established for assessing the impact of plasma diffusion on burn processes.