Discharge efficiency in high-Xe-content plasma display panels

We study theoretically the overall output performance and the dominating reaction processes of the vacuum ultraviolet (UV) radiation production in high-Xe partial pressures in plasma display panels (PDPs) with Ne-Xe gas mixtures. A two-dimensional self-consistent fluid model is applied for the simulations of discharges and UV radiation in sustaining phases of PDPs. The UV intensity increases with the Xe partial pressure (P-Xe). The discharge efficiency also increases with P-Xe. The resonant radiation from Xe(P-3(1)) dominates for 3.5%, while that from Xe-2((3)Sigma(u)(+)) becomes dominant over Xe(P-3(1)) for 10%-30%. Remarkably for 30%, the intensity from Xe-2((1)Sigma(u)(+)) is even larger than that from Xe(P-3(1)). It is found that for higher P-Xe, the UV radiation mainly consists of the excimer radiation from Xe-2((1)Sigma(u)(+)) and Xe-2((3)Sigma(u)(+)). Here, Xe(P-3(1)) does not play a role itself as the UV radiator of the resonant radiation (147 nm), but as the precursor to Xe-2((1)Sigma(u)(+)), which results in the excimer radiation (173 nm). (C) 2004 American Institute of Physics

Hypergravity diagnostics and material synthesis in noble gas gliding arc plasma

The behaviour of gliding arc discharge in argon and helium has been studied under normal gravity and hypergravity conditions. The similar influence of increased gas flow and increased gravity is reported. The measured electrical quantities show the differences between glide arc in argon and helium. Material synthesis of carbon nanomaterial has been carried out in mixture of helium with methane in both normal gravity and hypergravity

Hypergravity effects on glide arc plasma

The behaviour of a special type of electric discharge – the gliding arc plasma – has been investigated in hypergravity (1g –18g) using the Large Diameter Centrifuge (LDC) at ESA/ESTEC. The discharge voltage and current together with the videosignal from a fast camera have been recorded during the experiment. The gliding of the arc is governed by hot gas buoyancy and by consequence, gravity. Increasing the centrifugal acceleration makes the glide arc movement substantially faster. Whereas at 1g the discharge was stationary, at 6g it glided with 7 Hz frequency and at 18g the gliding frequency was 11 Hz. We describe a simple model for the glide arc movement assuming low gas flow velocities, which is compared to our experimental results

Exotische Plasma's: goed voor je gezondheid!

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Plasma Physics experiments

No abstract

Arcs: gravitational effects and pinching

Arcs are thermal plasmas: the temperatures of eletrons, ions and neutrals are roughly equal. In many cases, arcs are self-constricted. Two cases will be discussed: magnetically pinched arcs in Xe or Sn vapour (applied in EUV radiation sourcces) and AC arcs in metal halide vapours (used for lamps). In the first case, the pinching is essential for driving up the multiple ionisation to the required levels. For these arcs, we will look into sub-nanosecond phenomena. In the second case, the pinching is influenced by gravity. We will present measurements and simulations for gravity levels between 0 and 10 g