Non linear gyro-kinetic computation of turbulent transport in a fusion device

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This project aims at developing a software tool for the calculation of turbulence in a fully ionised gas embedded in a magnetic field. Such a turbulent system is observed to exist in the experimental reactors that aim at developing a future energy source based on the concept of nuclear fusion. The turbulence has a negative influence since it expels heat and particles reducing the efficiency of a reactor. It is,therefore, of importance to understand how the turbulence is generated and what its basic characteristics are. The numerical code developed in this project will help to achieve this goal.With a better understanding of the turbulent transport it is possible to predict the properties of a reactor concept without actually having to build it. Although it is unclear at present, it might be possible to optimise the design in a way that reduces the negative effects associated with the turbulent state. The starting point of the project is an existing linear stability code, with which one can determine if the plasma is unstable against small scale instabilities. Such a linear approach does not allow to determine how this initial instability will develop in time once its amplitude has grown to a significant level. For the latter case one needs to add the terms that describe the interaction between the different unstable modes. Goal of the project is to add these interaction terms. After the interaction terms have been added one faces a computationally demanding problem. Because of computer limitations, both in time as well as in memory, these computations can only be made on computers that combine many CPUs.