Simulation of flow around rigid vegetation stems with a fast method of high accuracy

This paper develops the virtual cylinder model (VCM) to simulate flows through vegetation canopies at low to medium high Reynolds numbers in wetlands. Using a combined Eulerian and Lagrangian approach, the VCM is capable of simulating the flow field around each vegetation stem (modeled as a cylinder) as well as a bulk of numerous stems in a fluid. Numerical results of flows through regularly and randomly arranged cylinders have been compared with direct numerical simulations. Good agreement has been achieved. This model maintains an excellent balance between accuracy and efficiency in modeling interactions between the fluid and vegetation stems. Simulation results demonstrate that this model is promising for investigating the hydrodynamics and vegetation resilience in wetlands that serve as a first line of defense against the sea level rise, storm impacts and coastal erosion.