Investigation of an Ablation-dominated Arc in a Model Chamber by Optical Emission Spectroscopy

Methling, Ralf; Khakpour, Alireza; Wetzeler, Sebastian; Uhrlandt, Dirk

doi:10.14311/ppt.2017.2.153

Cited by 2 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although an influence of the ignition wire can be proved to last up to 1 ms, the bright peak is much shorter, typically below 100 µs [16]. Next, the filling gas CO 2 causes an additional emission of carbon ionic C II lines (red) and of the oxygen lines (O I at 777 nm, not shown here).…”

Section: Video Observation and Flow Reversalmentioning

confidence: 71%

“…Under extreme conditions, i.e. for the setup (a) with the tubular PTFE nozzle exposed to high peak currents of 11 kA at 100 Hz, the lines of Cu I, C II and O I can have intensity peaks already 300-400 µs after ignition, while the F I emission (from PTFE) starts about 300-400 µs after ignition [16]. Approaching peak current (7.3 ms before CZ), also continuum radiation can be observed.…”

Section: Video Observation and Flow Reversalmentioning

confidence: 99%

See 1 more Smart Citation

Ablation-Dominated Arcs in CO2 Atmosphere - Part I: Temperature Determination near Current Zero

Methling¹,

Khakpour²,

Götte³

et al. 2020

Preprint

View full text Add to dashboard Cite

Wall–stabilized arcs dominated by nozzle–ablation are key elements of self–blast circuit breakers. In the present study, high–current arcs were investigated using a model circuit breaker (MCB) in CO2 as gas alternative to SF6 and in addition a long polytetrafluoroethylene nozzle under ambient conditions for stronger ablation. The assets of different methods for optical investigation were demonstrated, e.g. high-speed imaging with channel filters and optical emission spectroscopy. Particularly the phase near current zero (CZ) crossing was studied in two steps. In the first step using high-speed cameras, radial temperature profiles have been determined until 0.4 ms before CZ in the nozzle. Broad temperature profiles with a maximum of 9400 K have been obtained from analysis of fluorine lines. In the second step, the spectroscopic sensitivity was increased using an intensified CCD camera, allowing single-shot measurements until few microseconds before CZ in the MCB. Ionic carbon and atomic oxygen emission were analyzed using absolute intensities and normal maximum. The arc was constricted and the maximum temperature decreased from &gt;18000 K at 0.3 ms to about 11000 K at 0.010 ms before CZ. The arc plasma needs about 0.5-1.0 ms after both the ignition phase and the current zero crossing to be completely dominated by the ablated wall material.

show abstract

Section: Video Observation and Flow Reversalmentioning

confidence: 71%

Section: Video Observation and Flow Reversalmentioning

confidence: 99%

Ablation-Dominated Arcs in CO2 Atmosphere - Part I: Temperature Determination near Current Zero

Methling¹,

Khakpour²,

Götte³

et al. 2020

Preprint

View full text Add to dashboard Cite

show abstract

“…Obviously, the wire position was slightly off-axis for this shot. Although an influence of the ignition wire can be proved to last up to 1 ms, the bright peak is much shorter, typically below 100 µs [16]. Next, the filling gas CO 2 causes an additional emission of carbon ionic C II lines (red) and of the oxygen lines (O I at 777 nm, not shown here).…”

Section: Oes Of High-current Phase Using High-speed Cameramentioning

confidence: 71%

“…This emission was found to be visible in OES after 100-220 µs. Under extreme conditions, i.e., for the setup (a) with the tubular PTFE nozzle exposed to high peak currents of 11 kA at 100 Hz, the lines of Cu I, C II, and O I can have intensity peaks already at 300-400 µs after ignition, while the F I emission (from PTFE) starts at about 300-400 µs after ignition [16].…”

Section: Oes Of High-current Phase Using High-speed Cameramentioning

confidence: 99%

See 1 more Smart Citation

Ablation-Dominated Arcs in CO2 Atmosphere—Part I: Temperature Determination near Current Zero

et al. 2020

View full text Add to dashboard Cite

Wall-stabilized arcs dominated by nozzle–ablation are key elements of self-blast circuit breakers. In the present study, high-current arcs were investigated using a model circuit breaker (MCB) in CO2 as a gas alternative to SF6 (gas sulfur hexafluoride) and in addition a long polytetrafluoroethylene nozzle under ambient conditions for stronger ablation. The assets of different methods for optical investigation were demonstrated, e.g., high-speed imaging with channel filters and optical emission spectroscopy. Particularly the phase near current zero (CZ) crossing was studied in two steps. In the first step using high-speed cameras, radial temperature profiles have been determined until 0.4 ms before CZ in the nozzle. Broad temperature profiles with a maximum of 9400 K have been obtained from analysis of fluorine lines. In the second step, the spectroscopic sensitivity was increased using an intensified CCD camera, allowing single-shot measurements until few microseconds before CZ in the MCB. Ionic carbon and atomic oxygen emission were analyzed using absolute intensities and normal maximum. The arc was constricted and the maximum temperature decreased from >18,000 K at 0.3 ms to about 11,000 K at 0.010 ms before CZ. The arc plasma needs about 0.5–1.0 ms after both the ignition phase and the current zero crossing to be completely dominated by the ablated wall material.

show abstract

Investigation of an Ablation-dominated Arc in a Model Chamber by Optical Emission Spectroscopy

Cited by 2 publications

References 0 publications

Ablation-Dominated Arcs in CO2 Atmosphere - Part I: Temperature Determination near Current Zero

Ablation-Dominated Arcs in CO2 Atmosphere - Part I: Temperature Determination near Current Zero

Ablation-Dominated Arcs in CO2 Atmosphere—Part I: Temperature Determination near Current Zero

Contact Info

Product

Resources

About