Computational Fluid Dynamics (CFD) has become a mature technology in engineering design, contributing strongly to industrial competitiveness and sustainability across a wide range of sectors (e.g. transportation, power generation, disaster prevention). Future growth depends upon the exploitation of massively parallel HPC architectures, however this is currently hampered by performance scaling bottlenecks. The ambitious exaFOAM project aims to overcome these limitations through the development and validation of a range of algorithmic improvements. Improvements across the entire CFD process chain (pre-processing, simulation, I/O, post-processing) will be developed. Effectiveness will be demonstrated via a suite of HPC Grand Challenge and Industrial Application Challenge cases. All developments will be implemented in the open-source CFD software OpenFOAM, one of the most successful open-source projects in the area of computational modelling, with a large industrial and academic user base. To ensure success, the project mobilises a highly-capable consortium consisting of experts in HPC, CFD algorithms and industrial applications and includes universities, HPC centres, code release authorities and SMEs. Project management will be facilitated by a clear project structure and quantified objectives enable tracking of the project progress. Special emphasis will be placed on ensuring a strong impact of the exaFOAM project. The project has been conceived to address all expected impacts set out in the Work Programme. All developed code and validation cases will be released as open-source to the community in coordination with the OpenFOAM Governance structure. The involvement of 17 industrial supporters and stakeholders from outside the consortium underscores the industrial relevance of the project outcomes. A well-structured and multi-channelled plan for dissemination and exploitation of the project outcomes further reinforces the expected impact.