H-mode: Difference between revisions

191 bytes added ,  26 August 2009
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The steep edge gradients (of density and temperature) lead to quasi-periodic violent relaxation phenomena, known as Edge Localized Modes (ELMs), which have a strong impact on the surrounding vessel.
The steep edge gradients (of density and temperature) lead to quasi-periodic violent relaxation phenomena, known as Edge Localized Modes (ELMs), which have a strong impact on the surrounding vessel.
<ref>[http://dx.doi.org/10.1016/S0022-3115(97)80039-6 D.N. Hill, ''A review of ELMs in divertor tokamaks'', Journal of Nuclear Materials '''241-243''' (1997) 182-198]</ref>
<ref>[http://dx.doi.org/10.1016/S0022-3115(97)80039-6 D.N. Hill, ''A review of ELMs in divertor tokamaks'', Journal of Nuclear Materials '''241-243''' (1997) 182-198]</ref>
Although Quiescent H-modes exist (without ELMs), they are considered not convenient due to the accumulation of impurities.
Although Quiescent H-modes exist (without ELMs),
<ref>[http://link.aip.org/link/?PHPAEN/12/056121/1 K.H. Burrell et al, ''Advances in understanding quiescent H-mode plasmas in DIII-D'', Phys. Plasmas '''12''' (2005) 056121]</ref>
they are generally considered not convenient due to the accumulation of impurities.
To achieve steady state, an ELMy H-mode is preferred and this mode of operation is proposed as the standard operating scenario for [[ITER]], thus converting ELM mitigation into a priority.
To achieve steady state, an ELMy H-mode is preferred and this mode of operation is proposed as the standard operating scenario for [[ITER]], thus converting ELM mitigation into a priority.
<ref>[http://dx.doi.org/10.1016/j.fusengdes.2009.01.063 M.R. Wade, ''Physics and engineering issues associated with edge localized mode control in ITER'', Fusion Engineering and Design '''84''', Issues 2-6 (2009) 178-185]</ref>
<ref>[http://dx.doi.org/10.1016/j.fusengdes.2009.01.063 M.R. Wade, ''Physics and engineering issues associated with edge localized mode control in ITER'', Fusion Engineering and Design '''84''', Issues 2-6 (2009) 178-185]</ref>