Conveners
Modelling and simulations: Arc and plasma dynamics
- Matthew Hopkins (Sandia National Laboratories)
Modelling and simulations: Breakdown Models
- Chris Moore (Sandia National Labs)
Vacuum breakdown in the pulsed DC experiment at CERN was investigated by means of electrical measurements, SEM and STEM imaging of the surface and cross sections of the copper electrodes, and numerical modeling. The breakdown sites comprise one or more craters. There is plastic deformation beneath the craters.
The crater(s) represent the epicenter of the breakdown, where electron emission...
High-voltage accelerating structures (and other vacuum devices) are limited by the occurrence of vacuum arcs. To operate reliably such components must be subjected to a conditioning process in which the operating voltage is slowly increased over time while monitoring for arcs. This process is performed at great temporal and monetary expense, typically requiring millions of RF pulses or several...
The Voltage Holding Prediction Model (VHPM) is a design technique formulated at Consorzio RFX that combines numerical modelling and experimental data in order to calculate a breakdown probability curve. The cuve is based on the two parameters Weibull distribution for any multi-electrode multi-voltage vacuum insulated system under dc voltage. The progresses in employing the VHPM to predict the...
Almost 120 years after the isolation of vacuum arcs, the exact mechanisms of the arcs and the damage they produce are still being debated. We describe our simple and general model of the vacuum arc that can incorporate all active mechanisms and aims to explain all relevant data. Our four stage model, is based on experiments done at 805 MHz with a variety of cavity geometries, magnetic fields,...
