Sandia has developed a mobile acoustic Doppler velocimeter (ADV) system that characterizes inflow and wake flow velocity and turbulence around a vertical axis turbine deployed at the Roza Canal, Yakima, Washington. The ADV was mounted on a hydrofoil (see figure, left-hand panel) and deployed using either an aluminum platform mounted on a bridge (center panel) or using a cableway system (right-hand panel).
The Sandia team tested the system during a June 2014 site visit. The ADV has a 64 Hz sampling frequency and could be used to study the complex interaction between flow turbulence, turbine-generated power, and turbine wake dynamics. Spectral analyses on the flow turbulence and power generation data are being used to investigate the effect flow turbulence has on power generation. The measurements will also be used for validating numerical tools, such as the Sandia’s Environmental Fluid Dynamics Code (SNL-EFDC) model.
The Sandia team will make additional site visits to conduct more measurements with different turbine operation scenarios.