Determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at ASDEX upgrade
A heat pulse experiment was carried out in the tokamak ASDEX Upgrade to estimate the stochastic layer width of a deuterium L-mode discharge with externally applied Magnetic Perturbations. The method relies on the deposition of ECRH pulses in the plasma edge while measuring the divertor target heat f...
| Main Authors: | , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2017-08-01
|
| Series: | Nuclear Materials and Energy |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2352179116302150 |
| _version_ | 1818440409541509120 |
|---|---|
| author | D. Brida T. Lunt M. Wischmeier G. Birkenmeier P. Cahyna D. Carralero M. Faitsch Y. Feng B. Kurzan M. Schubert B. Sieglin W. Suttrop E. Wolfrum |
| author_facet | D. Brida T. Lunt M. Wischmeier G. Birkenmeier P. Cahyna D. Carralero M. Faitsch Y. Feng B. Kurzan M. Schubert B. Sieglin W. Suttrop E. Wolfrum |
| author_sort | D. Brida |
| collection | DOAJ |
| description | A heat pulse experiment was carried out in the tokamak ASDEX Upgrade to estimate the stochastic layer width of a deuterium L-mode discharge with externally applied Magnetic Perturbations. The method relies on the deposition of ECRH pulses in the plasma edge while measuring the divertor target heat flux with high temporal resolution IR thermography and Langmuir probes. The experimental results were compared to simulations of the time dependent heat pulse propagation on a constant plasma background with the EMC3-EIRENE code package, using an ad-hoc screening model. If no screening was taken into account in the simulations a decrease in the characteristic heat pulse propagation time was observed, which shows that the heat transport is enhanced compared to the screened cases. No such enhancement was found in the experiment, indicating strong screening. In further simulations the effect of screening on the target fluxes was investigated for varying densities. For low densities it was found that screening reduces the strike line splitting strongly, while for higher densities no strong strike line splitting was found, independent of the screening degree. For strongly detached L-mode conditions with MPs experiments at AUG indicate that the lobe structures vanish completely. Keywords: ASDEX upgrade, Magnetic perturbations, Divertor heat flux, MSC: 00-01, 99-00 |
| first_indexed | 2024-12-14T18:11:54Z |
| format | Article |
| id | doaj.art-1ca33ce8b62d459eae78650b10d2f3d6 |
| institution | Directory Open Access Journal |
| issn | 2352-1791 |
| language | English |
| last_indexed | 2024-12-14T18:11:54Z |
| publishDate | 2017-08-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Nuclear Materials and Energy |
| spelling | doaj.art-1ca33ce8b62d459eae78650b10d2f3d62022-12-21T22:52:16ZengElsevierNuclear Materials and Energy2352-17912017-08-0112831837Determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at ASDEX upgradeD. Brida0T. Lunt1M. Wischmeier2G. Birkenmeier3P. Cahyna4D. Carralero5M. Faitsch6Y. Feng7B. Kurzan8M. Schubert9B. Sieglin10W. Suttrop11E. Wolfrum12Corresponding author.; Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2., D-85748 Garching bei München, Germany; Physik-Department E28, Technische Universtität München, D-85747 Garching bei München, GermanyMax-Planck-Institut für Plasmaphysik, Boltzmannstr. 2., D-85748 Garching bei München, GermanyMax-Planck-Institut für Plasmaphysik, Boltzmannstr. 2., D-85748 Garching bei München, GermanyMax-Planck-Institut für Plasmaphysik, Boltzmannstr. 2., D-85748 Garching bei München, Germany; Physik-Department E28, Technische Universtität München, D-85747 Garching bei München, GermanyInstitute of Plasma Physics CAS, v.v.i. Prague, Czech RepublicMax-Planck-Institut für Plasmaphysik, Boltzmannstr. 2., D-85748 Garching bei München, GermanyMax-Planck-Institut für Plasmaphysik, Boltzmannstr. 2., D-85748 Garching bei München, GermanyMax-Planck-Institut für Plasmaphysik, 17491 Greifswald, GermanyMax-Planck-Institut für Plasmaphysik, Boltzmannstr. 2., D-85748 Garching bei München, GermanyMax-Planck-Institut für Plasmaphysik, Boltzmannstr. 2., D-85748 Garching bei München, GermanyMax-Planck-Institut für Plasmaphysik, Boltzmannstr. 2., D-85748 Garching bei München, GermanyMax-Planck-Institut für Plasmaphysik, Boltzmannstr. 2., D-85748 Garching bei München, GermanyMax-Planck-Institut für Plasmaphysik, Boltzmannstr. 2., D-85748 Garching bei München, GermanyA heat pulse experiment was carried out in the tokamak ASDEX Upgrade to estimate the stochastic layer width of a deuterium L-mode discharge with externally applied Magnetic Perturbations. The method relies on the deposition of ECRH pulses in the plasma edge while measuring the divertor target heat flux with high temporal resolution IR thermography and Langmuir probes. The experimental results were compared to simulations of the time dependent heat pulse propagation on a constant plasma background with the EMC3-EIRENE code package, using an ad-hoc screening model. If no screening was taken into account in the simulations a decrease in the characteristic heat pulse propagation time was observed, which shows that the heat transport is enhanced compared to the screened cases. No such enhancement was found in the experiment, indicating strong screening. In further simulations the effect of screening on the target fluxes was investigated for varying densities. For low densities it was found that screening reduces the strike line splitting strongly, while for higher densities no strong strike line splitting was found, independent of the screening degree. For strongly detached L-mode conditions with MPs experiments at AUG indicate that the lobe structures vanish completely. Keywords: ASDEX upgrade, Magnetic perturbations, Divertor heat flux, MSC: 00-01, 99-00http://www.sciencedirect.com/science/article/pii/S2352179116302150 |
| spellingShingle | D. Brida T. Lunt M. Wischmeier G. Birkenmeier P. Cahyna D. Carralero M. Faitsch Y. Feng B. Kurzan M. Schubert B. Sieglin W. Suttrop E. Wolfrum Determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at ASDEX upgrade Nuclear Materials and Energy |
| title | Determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at ASDEX upgrade |
| title_full | Determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at ASDEX upgrade |
| title_fullStr | Determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at ASDEX upgrade |
| title_full_unstemmed | Determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at ASDEX upgrade |
| title_short | Determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at ASDEX upgrade |
| title_sort | determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at asdex upgrade |
| url | http://www.sciencedirect.com/science/article/pii/S2352179116302150 |
| work_keys_str_mv | AT dbrida determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT tlunt determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT mwischmeier determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT gbirkenmeier determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT pcahyna determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT dcarralero determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT mfaitsch determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT yfeng determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT bkurzan determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT mschubert determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT bsieglin determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT wsuttrop determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade AT ewolfrum determinationofthestochasticlayerpropertiesinducedbymagneticperturbationsviaheatpulseexperimentsatasdexupgrade |