A Physics-Based Actuator Disk Model for Hydrokinetic Turbines

Bowman, J., Bhushan, S., Thompson, D., O'Doherty, D., O'Doherty, T., & Mason-Jones, A. (2018). A Physics-Based Actuator Disk Model for Hydrokinetic Turbines. 2018 Fluid Dynamics Conference, AIAA AVIATION Forum, (AIAA 2018-3227). Atlanta, GA: AIAA. DOI:10.2514/6.2018-3227.

Abstract

A physics-based actuator disk model (PBADM) was derived using blade-resolved turbine LES wake data for a blade/hub configuration and was incorporated into a RANS implementation in OpenFOAM. The PBADM attempts to address the limitations of the currently available actuator disk models. The development of the PBADM employed the use of mean streamwise and tangential velocity profiles in the near-wake region from a blade-resolved blade/hub simulation. Radially-varying axial and tangential induction factors were obtained from the mean streamwise and tangential velocity profiles. These induction factors were then used to define a body-force that was included in the momentum equation. The uniformly-loaded actuator disk model, non-uniformly-loaded actuator disk model, and the virtual blade model were compared to the PBADM. The results from these simulations were compared to experimental data with a stanchion. The mean streamwise deficit of the PBADM was similar to that of the blade-resolved solution. The comparison of the transverse velocity showed large differences and should be further investigated. Future work will focus on developing models using results from additional simulations for the model-scale geometry as well as other experimental results to calibrate the PBADM.