Case Study: Dynamic Analysis of a Novel Vertical Axis Wind Turbine

An analytical model was developed for the dynamic evaluation of a novel vertical axis wind energy system. This study was conducted early on in the design process, so the goal was to create a low level tool to determine if the concept was feasible, to perform initial sizing of the turbine, to better understand the behavior of the unique furling mechanisms, and to predict the performance. In order to prevent damage at high rotational speeds, the novel concept integrates passive mechanisms into a drag driven vertical axis wind turbine with the intention that blades furl out of the wind once a critical wind speed is reached, and passively reopen. Established wind turbine aeroelastic codes were unable to represent this unique system, therefore, a standalone analytical model was developed in Python. A Lagrangian approach was taken to represent the interactions of the system’s degrees of freedom. To complete the model, mathematical representations of the furling mechanisms and interaction of the wind on the blades was developed. Basic structural calculations were also included to determine the initial size of the primary mechanical components. This case study focuses on the development of the low-level dynamic model and shares several results of the expected behavior.