Experiments on Arc Perturbation in Turbulent Gas Flow

Self Cite

By inei~ns of the short-circuiting of electric arcs burning in turbulent axial gas coolant flow and their rcaction on a (recovering) voltage ramp the reignition in circuit breakers is modelled. Strong stochasticity of thermal reignition is demonstrated even under relatively weak conditions. Channels or nozzles showing flow detachment are further deteriorated by that. Corresponding low-current test experiments are recommended for in-scale circuit breaker development tests.

“…The axial velocity of the deformations of the arc is constant. (dr/dt e 0) in the jet, whereas in the constant area channel t,he kinematics of the disturbances is accelerated [8]. Tab.…”

Section: Reignition Under Flow Dedachment Conditionsmentioning

confidence: 99%

Perturbed Arcs in Turbulent Axial Gas Flow IV. Thermal Reignition Experiments

Rothhardt

Michel

1985

Self Cite

“…In two preceding papers we discussed spatial disturbances on arcs in strongly turbulent axial gas flow [l] and the avaraged properties of these arcs and their embedding' medium [2]. In this paper we report on local measurements for more detailed information concerning turbulency in the gas coolant.…”

Section: Introductionmentioning

confidence: 98%

Perturbed Arcs in Turbulent Axial Gas Flow II. Fluctuating Local Properties

Michel¹,

Rothhardt²

1984

Self Cite

Perturbed Arcs in Turbulent Axial Gas Flow. I. Averaged Properties and Power Balance

Michel

Rothhardt

1984

Electric, caloric, radiation and sounding m~~asumiients are reported, which were done with an nitrogen arc in strongly turbulent gas coolmt flow. On the base of this measurements a power balance is established. It allows for the description of the arc by a three-zone-model, the zones being 1. conducting arc core, 2. thermal shetat11 cmtnining dissociated nitrogen, 3. relatively cold coolant gas. The hot arc core is gliding iIlside of the thermal sheath. The geometrical disturbances, discussed in a preceding papers do 8% too. The dominating power loss is by axial enthalpy flow out of the channel, carried by the dissociated nitrogen in the thermal sheath.