Affiliations: [a] Accelerator and Pulse Power Division, Bhabha Atomic
Research Centre, Mumbai, India
Correspondence:
[*]
Corresponding author: C.S. Reddy, Accelerator and Pulse Power
Division, Bhabha Atomic Research Centre, HomiBhabha National Institute, Mumbai,
India. Tel.: +91 98 6970 4298; E-mail: [email protected]
Abstract: The recovery in a spark gap for repetitive switching has been a long
research interest. The surface temperature variation of the anode during
switching plays decisive role in recovery of spark gap. This paper presents a
method to estimate the effect of anode temperature rise and decay on repetition
rate of spark gap. By using this method, the behavior of copper and stainless
steel materials were studied for a current pulse of 30 kA. During the pulse
period of 10 μs, the temperature rise for SS is higher
than Copper. After current zero, the anode temperature decays to the
vaporization temperature of the material and determines the recovery time of
the spark gap. This temperature decay is also verified by a heat transient
computational model developed in FEM based software. Simulations has been
carried out for different materials including Cu and SS. Some simulations are
in good agreement with existing experimental data. The decay time for current
pulses 5 kA, 10 kA, 15 kA, 20 kA, 25 kA and 30 kA are estimated. The simulation
shows higher decay rate for tungsten and lower decay rate for graphite. Similar
trend has been observed for silver and copper. Theoretical analysis of recovery
times, heat transfer simulation model for different anode materials are
presented and the results are discussed.
Keywords: Anode temperature recovery, anode materials, spark gap recovery, specific heat flux, vaporization
