Kinetic Equilibrium Prediction at TCV using RAPTOR and FBT

C. E. Contré; A. Merle; O. Sauter; S. Van Mulders; R. Coosemans; G. Durr-Legoupil-Nicoud; F. Felici; O. Février; C. Heiss; B. Labit; A. Pau; Y. Poels; C. Venturini; B. Vincent; the TCV team; the EUROfusion Tokamak Exploitation Team

doi:10.1088/1741-4326/ae7e6d

arXiv · 2603.01210

Kinetic Equilibrium Prediction at TCV using RAPTOR and FBT

C. E. Contré·A. Merle·O. Sauter·S. Van Mulders·R. Coosemans·G. Durr-Legoupil-Nicoud·F. Felici·O. Février·C. Heiss·B. Labit·A. Pau·Y. Poels·C. Venturini·B. Vincent·the TCV team·the EUROfusion Tokamak Exploitation Team

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Abstract

We present results from a new Kinetic-Equilibrium Prediction (KEP) workflow and shot preparation for full TCV discharges, by coupling predict-first RAPTOR transport simulations with FBT inverse equilibrium calculations. RAPTOR is a 1.5D transport code which has been extensively used for plasma shot optimization and real-time modeling. We show that rapid pre-shot simulations can be performed directly using information from the pulse schedule across a wide range of plasma shapes and scenarios, given an estimate of the confinement quality factor H98(y,2) and line-averaged density. The resulting p' and TT' profiles are then provided to the pre-shot equilibrium computation performed by FBT - a static free-boundary solver routinely used at TCV - achieving convergence between the two codes in a few iterations. Finally, we show that this coupling, when integrated into the TCV shot preparation, improves the evaluation of the coil currents needed to match the target plasma shape; in particular providing an accurate estimate of critical quantities such as the internal inductance $l_i$ and normalized pressure $\beta_N$, giving more realistic information to tokamak operators about the expected pulse behavior and enabling them to adjust the plan correspondingly.

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C. E. Contré, A. Merle, O. Sauter, S. Van Mulders, R. Coosemans, G. Durr-Legoupil-Nicoud, F. Felici, O. Février, C. Heiss, B. Labit, A. Pau, Y. Poels, C. Venturini, B. Vincent, the TCV team, the EUROfusion Tokamak Exploitation Team. 2026-03-01. Kinetic Equilibrium Prediction at TCV using RAPTOR and FBT. https://doi.org/10.1088/1741-4326/ae7e6d

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