Abstract
Using the TRANSP code as a reference, the accuracy of predictions by the simpler and much faster PENCIL code has been checked in several Joint European Torus (JET) plasma regimes. For sufficiently dense plasmas ( ``approx.`` 1.5 {center_dot} 10{sup 19} m{sup -3}) and far enough away from large steps in the input power (t > ``approx.`` t{sub STEP} + 0.5 sec) global and local predictions by PENCIL and TRANSP are found to be in excellent agreement. PENCIL can thus be confidently used as a fast and inexpensive computational tool for most transport studies of neutral beam injection (NBI) heated plasmas in JET. On the other hand, PENCIL results should not be trusted in strongly transient conditions (such as the early phase of a high-power NBI heating pulse) and in very low density regimes (when losses via charge-exchange processes can be a significant fraction of the input power). In these situations, TRANSP has to be used to obtain reliable results. We also briefly discuss the sensitivity of PENCIL results to the uncertainties associated with the JET experimental data used as input. As a by-product of these comparisons, we investigate the uncertainties inherent in the simulation of D-D neutron yields
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Citation Formats
Corrigan, G, Muir, D G, and Tibone, F.
Neutral beam-plasma interaction in JET: comparison of PENCIL and TRANSP modelling results.
United Kingdom: N. p.,
1992.
Web.
Corrigan, G, Muir, D G, & Tibone, F.
Neutral beam-plasma interaction in JET: comparison of PENCIL and TRANSP modelling results.
United Kingdom.
Corrigan, G, Muir, D G, and Tibone, F.
1992.
"Neutral beam-plasma interaction in JET: comparison of PENCIL and TRANSP modelling results."
United Kingdom.
@misc{etde_10142647,
title = {Neutral beam-plasma interaction in JET: comparison of PENCIL and TRANSP modelling results}
author = {Corrigan, G, Muir, D G, and Tibone, F}
abstractNote = {Using the TRANSP code as a reference, the accuracy of predictions by the simpler and much faster PENCIL code has been checked in several Joint European Torus (JET) plasma regimes. For sufficiently dense plasmas ( ``approx.`` 1.5 {center_dot} 10{sup 19} m{sup -3}) and far enough away from large steps in the input power (t > ``approx.`` t{sub STEP} + 0.5 sec) global and local predictions by PENCIL and TRANSP are found to be in excellent agreement. PENCIL can thus be confidently used as a fast and inexpensive computational tool for most transport studies of neutral beam injection (NBI) heated plasmas in JET. On the other hand, PENCIL results should not be trusted in strongly transient conditions (such as the early phase of a high-power NBI heating pulse) and in very low density regimes (when losses via charge-exchange processes can be a significant fraction of the input power). In these situations, TRANSP has to be used to obtain reliable results. We also briefly discuss the sensitivity of PENCIL results to the uncertainties associated with the JET experimental data used as input. As a by-product of these comparisons, we investigate the uncertainties inherent in the simulation of D-D neutron yields in high-performance JET discharges such as those used for the Preliminary Tritium Experiment. It is shown that - given the margins of error on the measured plasma profiles - the thermal neutron rate (typically half of the total in the hot-ion H-mode regime) cannot be simulated by either PENCIL or TRANSP with an accuracy better than {+-} 40%. Further uncertainty arises from the choice of nuclear cross-sections and flux surface geometry. (author).}
place = {United Kingdom}
year = {1992}
month = {Jan}
}
title = {Neutral beam-plasma interaction in JET: comparison of PENCIL and TRANSP modelling results}
author = {Corrigan, G, Muir, D G, and Tibone, F}
abstractNote = {Using the TRANSP code as a reference, the accuracy of predictions by the simpler and much faster PENCIL code has been checked in several Joint European Torus (JET) plasma regimes. For sufficiently dense plasmas ( ``approx.`` 1.5 {center_dot} 10{sup 19} m{sup -3}) and far enough away from large steps in the input power (t > ``approx.`` t{sub STEP} + 0.5 sec) global and local predictions by PENCIL and TRANSP are found to be in excellent agreement. PENCIL can thus be confidently used as a fast and inexpensive computational tool for most transport studies of neutral beam injection (NBI) heated plasmas in JET. On the other hand, PENCIL results should not be trusted in strongly transient conditions (such as the early phase of a high-power NBI heating pulse) and in very low density regimes (when losses via charge-exchange processes can be a significant fraction of the input power). In these situations, TRANSP has to be used to obtain reliable results. We also briefly discuss the sensitivity of PENCIL results to the uncertainties associated with the JET experimental data used as input. As a by-product of these comparisons, we investigate the uncertainties inherent in the simulation of D-D neutron yields in high-performance JET discharges such as those used for the Preliminary Tritium Experiment. It is shown that - given the margins of error on the measured plasma profiles - the thermal neutron rate (typically half of the total in the hot-ion H-mode regime) cannot be simulated by either PENCIL or TRANSP with an accuracy better than {+-} 40%. Further uncertainty arises from the choice of nuclear cross-sections and flux surface geometry. (author).}
place = {United Kingdom}
year = {1992}
month = {Jan}
}