Experimental Analysis of a Biplane Wells Turbine under Different Load Conditions

Abstract

The oscillating water column type wave energy converters equipped with Wells turbine are one of the popular wave energy conversion devices. In most of the numerical and experimental studies, the Wells turbine characteristics are examined in no-load condition or with a fixed loading to achieve a fixed rotational speed. In the present work, a biplane Wells turbine is designed and tested in an experimental test facility. The test facility consists of a piston-chamber assembly that can generate sinusoidal airflow inside a duct. The turbine is placed inside the duct and tested for different stroke lengths and time periods of the piston, which produces a sinusoidal inlet airflow of different amplitude and time period. The turbine characteristics are studied at the no-load condition and for different values of resistive loading connected with the generator. The hysteresis behavior of the turbine is studied for two different flow coefficients based on experimentally observed and numerically calculated volume flow rates. Based on the experimental results, a detailed analysis of the turbine performance is presented for different operating conditions.