Experimental and Numerical Analysis of a Scale-Model Horizontal Axis Hydrokinetic Turbine

This paper presents an experimental/numerical study of a scale-model Horizontal Axis Hydrokinetic Turbine (HAHT). The model turbine is based on the DOE Reference Model 1 (DOE RM1), with a modified geometry to reproduce performance at the flume scale Reynolds numbers. These modifications were necessary to overcome the strong Reynolds number effect on the NACA–6 airfoil family used on the design, and therefore on the device performance in experimental analysis. The performance and wake structure of a single turbine was analyzed with measurements conducted on a 45:1 scale physical model of the modified design of the DOE RM1 rotor. The details of the rotor flow field and wake evolution are analyzed from numerical solution of the RANS equations solved around a computational model of the scale-model turbine. A comparison between the experimental and numerical results is presented. These comparisons highlight the strengths as well as limitations of the experimental and numerical analysis for these types of HAHT characterizations. On a more general sense, these comparisons provide useful guidelines for developing a set of experimental flume scale data and to use it to validate numerical tools, and as pilot projects start to go in the water in the US, to perform a similar type of analysis and design validation of full scale devices.