1. A system for executing a given scientific code using a suitable finite-volume or finite-element solver for a large dataset represented as a grid, comprising a plurality of equal computing nodes and a front-end node, all of them interconnected by node communication, and a parallel computing software package for distributing the execution of said scientific code in sub-grids of said grid among said computing nodes, wherein: each computing node comprises at least a first processor and a second processor, which are interconnected by a bus, said first processor being a CPU-based processor and said second processor being a FPGA-based processor; said parallel computing software package being configured for simultaneous execution of at least one first solver process and one second solver process of said scientific code in each computing node, where each solver process solves at least one sub-grid of said grid, and for managing the exchange of boundary data between the first and second solver processes that compute neighbour sub-grids after each step of the solver; wherein said first solver process is fully executed in the first processor and said second solver process is executed in the second processor with the collaboration of the first processor for loading and unloading the sub-grid and the exchange of boundary data; and wherein said first and second solver processes have the same communication interface for exchanging boundary data with the first and second solver processes that solve neighbour sub-grids.