Structure design and analysis of RF ion source for negative ion source test facility.

Area of Science:

• Plasma Physics
• Fusion Energy Engineering

Background:

• Negative ion sources are crucial components for neutral beam injectors (NBI) in high-power fusion devices.
• High current negative ion sources are essential for efficient NBI operation.

Purpose of the Study:

• To develop and demonstrate a prototype radio frequency (RF) negative ion source and its test facility.
• To present the structural design and analysis of key components for high-power negative ion sources.

Main Methods:

• Detailed structural design and finite element analysis (FEA) of the ion source plasma generator, accelerator, Faraday shield (FS), and accelerator grids.
• Exploration of fluid-thermal-structural coupling characteristics under various operational conditions (fluid pressure, RF power, structure type).
• Development of processing and manufacturing schemes for the FS and grids.

Main Results:

• A prototype RF negative ion source with a three-cooling-channel FS was successfully manufactured.
• FEA revealed the impact of operational parameters and structural design on thermal stress.
• Experimental validation confirmed the effectiveness and reliability of the developed RF ion source design.

Conclusions:

• The developed RF negative ion source structure is effective and reliable for high-power NBI applications.
• The finite element analysis methods used were validated by experimental data.
• This work demonstrates key technology for future high-power negative ion sources in fusion research.