Description Flows through pipes or channels that exhibit a change in their cross-section, like contractions and expansions, are ubiquitous in nature (eg. in blood vessels) and important in many industrial applications (eg. pipelines, processing units). In expansion flows, even the flow of Newtonian fluids at low to moderate Reynolds number reveal complex flow patterns with the formation of recirculating structures. In many realistic situations the fluids flowing through the flow devices are non-Newtonian exhibiting a shear-thinning or shear-thickening behaviour that significantly alter the flow field. The knowledge of the flow field is crucial both to design and develop more efficient processes and to improve the quality control of the final products. In this project the flow field of shear-thinning fluids through contraction-expansion will be studied using numerical simulations. Key Objectives Perform a literature survey on expansion flows and shear-thinning fluids Mesh the selected geometriesPerform numerical simulations using CFD software (OPENFOAM or ANSYS or STAR-CCM+)Validate the numerical results by comparison with experimental data available in the literatureAnalyse the flow field and evaluate the effects of the shear-thinning behaviour