Shatter Thresholds and Fragment Size Distributions of Deuterium–Neon Mixture Cryogenic Pellets for Tokamak Thermal Mitigation
Reliable mitigation is necessary to eliminate the detrimental effects of a disruption event in large high-current tokamaks such as ITER. To avoid serious damage to plasma-facing components during the thermal quench phase of a disruption, material is injected to radiate the plasma energy over the inner surface of the machine. The most promising method of material injection is a process known as shattered pellet injection (SPI). SPI utilizes cryogenic cooling to desublimate gas into the barrel of a pipe gun to form a solid pellet. High-pressure gas or a mechanical punch is used to dislodge the pellet and accelerate it into a bent tube to intentionally fracture it. Pellets made of a mixture of deuterium and neon are likely candidates for thermal mitigation. The survivability of these pellets throughout their flight path, before striking the shatter tube, is essential for reliable SPI operation. Experiments were conducted to determine intact speed limits for various mixtures. In this paper, we outline the details of brittle fracture theory and compare a theory-based model to experimental results from various mixtures of deuterium and neon pellets.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- Grant/Contract Number:
- AC05-00OR22725
- OSTI ID:
- 1661244
- Journal Information:
- Fusion Science and Technology, Vol. Online, Issue Online; ISSN 1536-1055
- Publisher:
- American Nuclear SocietyCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Development of Solenoid-Driven and Pneumatic Punches for Launching High- Z Cryogenic Pellets for Tokamak Disruption Mitigation Experiments
|
journal | May 2019 |
First demonstration of rapid shutdown using neon shattered pellet injection for thermal quench mitigation on DIII-D
|
journal | March 2016 |
Disruption Mitigation System Developments and Design for ITER
|
journal | September 2015 |
Solid solutions Ne–nD2. Diagram of phase equilibrium
|
journal | November 2005 |
Similar Records
Pressure Response Optimization of an Eddy Current-Driven Flyer Plate Valve for the ITER Shattered Pellet Injection System
Development of Solenoid-Driven and Pneumatic Punches for Launching High-Z Cryogenic Pellets for Tokamak Disruption Mitigation Experiments