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OpenFOAM modeling of a Momentum Reversal and Lift Tidal Turbine Gussoni Enrico Levi Reem Muscari Claudia Padricelli Claudio September 12, 2018 Contents 1 Introduction 2 2 Description of the problem 3 3 Input Data 4 4 Discretization phase 5 4.1 Space discretization: creation of the mesh . . . . . . . . . . . 5 4.2 Boundary conditions . . . . . . . . . . . . . . . . . . . . . . . 9 5 1st simulation 12 6 Turbulent modeling 13 7 Numerical schemes 18 7.1 Time schemes . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 7.2 Space schemes . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 7.3 Convergence . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 8 Mesh sensitivity analysis 22 9 Characteristic curve of the machine 26 10 Conclusion 28 1 Chapter 1 Introduction This project has been developed in the context of the course ofModeling Techniques for Fluid Machinesin theInternal Combustion Engines and Tur- bomachinery masterof Mechanical EngineeringatPolitecnicodiMilano. The objective was to apply the CFD concepts presented during the course to a real case and to study the variation of the final result with different solution strategies and parameters. More specifically the simulations has been done with OpenFOAM software. In this document the process steps that lead to our results will be described and explained in detail. Figure 1.1: Momentum Reversal and Lift tidal turbine 2 Chapter 2 Description of the problem As said before, the subject of the study is aMomentum Reversal and Lift (MRL) tidal turbine designed by AquaScientific Ltd. The most relevant aspect of this machine is the complex motion of its sub-parts. There is a rel- ative motion of the fluid with respect to the turbine and of the three blades with respect to the turbine itself. A moving mesh is…