The objective of NextMuSE is to initiate a paradigm shift in the technology of Computational Fluid Dynamics (CFD) and Computational Multi-Mechanics (CMM) simulation software which is used to model physical processes in research and technology development across a range of industries. NextMuSE relies on a mesh-free method, Smoothed Particle Hydrodynamics (SPH), which is fundamentally different from conventional techniques and can overcome their shortcomings. The NextMuSE paradigm is defined by two characteristics: - accurate robust multi-mechanics modelling in applications where traditional methods fail (e.g. simultaneous fluid and solid mechanics in a ship under extreme wave loading). - an immersive, interactive user interface (ICARUS) to allow the user-engineer to manage and partially automate the extremely complex inputs and outputs of such multi-mechanics simulations. The objectives will be achieved through 7 work packages. 1: Key enhancements of core SPH algorithms. 2: Adapted physical modelling of fluids: turbulence, multiphase flow. 3: Modelling of fluid-structure interaction. 4: High-performance computing: highly efficient scalable algorithms for very large simulations. 5: Development of an immersive and highly visual simulation/design environment to interact with the technology. 6: Realistic representative applications in the marine, energy and biomedical industries. 7: Dissemination, communication and exploitation. This project will remove technology roadblocks and enable an enhanced and extended role for ICT and HPC in socio-economically important engineering RTD and innovation sectors (including energy, healthcare and transport). Although there are challenging scientific bottlenecks, risk is managed and minimised through the design of the work plan and the selection of the consortium. The risk is balanced by the potential reward for this project, which is a proof-of-concept for a paradigm shift which will open the way for advanced immersive HPC simulation tools, seamlessy integrated into the RTD process for the most challenging engineering problems.