Pressure evolution during HBC fuse operation

Abstract

The purpose of this paper is to describe the influence of the silica sand grains on pressure during the energy release in a high breaking capacity (HBC) fuse. During the HBC fuse operation, the pressure evolution is the result of two opposite trends: the pressure increase due to the interaction of the silica plasma with the surrounding granular sand, and the pressure decrease due to the propagation of the pressure waves toward the porous medium. Due to the complex phenomena occurring during the current extinction by a fuse, two kinds of pressure are distinguished: the pressure inside the silica plasma and the pressure in the silica sand. From the simulations we show that the Forchheimer flow resistance is stronger than the Darcy flow resistance once the electric power is over 30% of the maximum value. A comparison of the calculated and measured pressures is made at various positions from the fuse element axis. Two different pressures are obtained experimentally: the pressure P SAND exerted on the sand grains due to the plasma pressure, and the pressure P GAS of the gas flowing through the interstices of the silica sand. We show that the experimental and calculated trends are similar and they both depend on the electric power level and the silica sand mean granulometry. The maximum pressures are observed at the same time as the maximum electric power levels. The ratio P SAND /P GAS is about 8 with P GAS values not exceeding 1.5 × 10 5 Pa.

Transport Coefficients of Ag–SiO2 Plasmas

“…with the internal conductivity of the i chemical species k inti ¼ PD ii 1 ð Þ T C pi R À 5 2 and the use of the first approximation for the binary diffusion coefficients:…”

“…Then the temperature increasing combined to the material vaporization lead to a pressure enlargement. From experimental tests, Rochette et al [2] obtained pressure measurements in the range of 1-30 atm for high breaking capacity fuses. But also a fulgurite is formed, when the arcing appears in the fuses, which leads to a shorter circuit current interruption time.…”

“…But also a fulgurite is formed, when the arcing appears in the fuses, which leads to a shorter circuit current interruption time. Due to the complex arcing phenomena (as an example, the dynamics of the fulgurite formation, governed by the plasma evolution during the process, is quite unknown) and the experimental difficulties [2], researchers have a main interest to explain the experimental results with the help of a theoretical approach.…”

Increasing Arc Column Resistance During DC Arc‐Quenching Through Arrangement of Polymer Cylinder in Silica Sand

“…The chemical potentials were calculated using the partition functions of the chemical species [26–28]. According to the literature, the pressure inside a fuse that used silica sand can increase to approximately 1.0 MPa during arc extinction [14]. Therefore, the pressure was assumed to be 1.0 MPa in these calculations.…”

“…They have primarily investigated the effects of silica sand granulometry [9], silica sand packing method [10], and fuse element shape [10][11][12][13] on arc quenching. Experimental measurements [11,14,15] and numerical simulations [16,17] have been conducted to analyze the pressure, arc temperature, and electron density within a fuse.…”