Pressure Rise and Propagation Phenomena Due to Fault Arc in Container with Opened Pipe

Abstract

SUMMARYThis paper describes experimental and analytic studies on pressure rise and propagation phenomena due to high current arcs in a container with opened pipes. The shape of the experimental container was chosen taking into account underground common ducts. First, arcs were ignited in the container with varying diameter D and length L of the opened pipes and at arc currents of 4 kA to 12.5 kA and an arc duration of 0.1 s. Based on measured waveforms, the maximum pressure rise P and the pressure oscillation frequency P were obtained. It was found that there is a tendency for P to increase with decreasing D and increasing L, and that D has a much greater impact on P . In addition, the tendencies of P with changing D and L can be approximately explained by Helmholtz resonance. Second, a CFD model for the container with opened pipe was developed based on the experimental results, and simulations were performed. The simulation results were found to correspond to the experimental pressure rise. C⃝ 2014 Wiley Periodicals, Inc. Electr Eng Jpn, 190(3): 30-36, 2015; Published online in Wiley Online Library (wileyonlinelibrary.com).

Experimental investigation of thermal transfer coefficient by a simplified energy balance of fault arc in a closed air vessel

“…Zhang et al [4,5] combined hydroand thermodynamic equations to evaluate the pressure rise due to fault arc in an electrical installation, in which the fault arc is simplified as a heat source. Experimental work on fault arcs has also been reported recently [6][7][8]. Pettinga et al [9] studied experimentally the relationship between arc temperature and pressure of fault arc in an MV switchgear filled with air or SF 6 .…”