Eric Violard

Learn More
The impact of large scale flows on turbulent transport in magnetized plasmas is explored by means of various kinetic models. Zonal flows are found to lead to a non-linear upshift of turbulent transport in a 3D kinetic model for interchange turbulence. Such a transition is absent from fluid simulations, performed with the same numerical tool, which also(More)
We present load-balancing strategies to improve the performances of parallel MPI applications running in a Grid environment. We analyze the data distribution constraints found in two scientific codes and propose adapted code transformations to load-balance computations. Experimental results confirm that such source code transformations can improve Grid(More)
This paper presents an efficient parallel implementation of a Vlasov solver. Our implementation is based on an adaptive numerical scheme of resolution. The underlying numerical method uses a dyadic mesh which is particularly well suited to manage data locality. We have developed an adapted data distribution pattern based on a division of the computational(More)
Parallel programs mainly diier from sequential ones in that they include geometrical aspects involved by the hardware architecture. We present in this paper the Pei formalism, which enables to take into account both the geometrical and functional aspects of programs. It provides a reenement calculus mainly used to transform the geometrical characteristics(More)