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This contribution presents preliminary results of the validation of state-of-the-art turbulence codes against well-diagnosed experiments in the TCV tokamak. The simulations were carried out by GBS, GRILLIX, and TOKAM3X codes for a Lower Single-Null (LSN) L-mode attached TCV plasma and, for the first time, in realistic size. The scenario depicted in the simulations was developed in the TCV tokamak and was optimized for this validation exercise. In the following, the level-of-agreement and comparisons of selected profiles are discussed.

In the most important future fusion devices, like ITER, the core temperature and fusion performance will strongly depend on electron heat transport, which is dominated by turbulent processes. Electron Temperature Gradient (ETG) micro-turbulence modes have been recently shown to impact the electron heat transport in tokamaks in conditions when ion-scale turbulence is close to marginality and electron heating is significant.

Corroborating evidence is presented that the sawtooth period can follow the modulation frequency of an externally applied high power electron cyclotron wave source. Precise, fast and robust open loop control of the sawtooth period with a continuously changing reference period has been achieved. This period locking is not associated with the crash, but with the phase evolution of the inter-crash dynamics. This opens new possibilities of open loop control for physics studies and maybe for reactor performance control.