An improved vertical axis wind turbine model based on high Reynolds number dynamic stall data

Vertical axis wind turbines (VAWTs) offer some advantages over conventional horizontal axis wind turbines for certain use cases, but their performance is challenging to model due to the unsteady aerodynamics involved. Past studies have modeled VAWTs using a BEM-type approach known as double multiple stream tube (DMST) models. However, these models typically rely on tabulated lift and drag data from static airfoil experiments, but VAWTs are prone to experiencing dynamic stall over a wide range of operating conditions. Dynamic stall leads to momentary flow separation on the blades, resulting in large oscillations in the forces they experience. To accurately predict turbine power output in such conditions, dynamic stall effects need to be included in DMST models. Here we incorporate dynamic stall data from 2D airfoil experiments at high Reynolds numbers into the DMST model developed by Ayati et al. (2019) and validate the results against high Reynolds number experimental data of VAWT performance from Miller et al. (2018). All experimental data was acquired in the High Reynolds number Test Facility at Princeton University.