Performance comparison of turbines for bi-directional flow

Abstract

Bi-directional airflow is generated in the wave energy plant with oscillating water column (OWC). Turbines for bi-directional airflow have been used in such devices, and they rotates in the same direction. Some turbines for bi-directional airflow were proposed, and their performance were investigated by wind tunnel tests and CFD analyses. Typical turbines have some inherent disadvantages such as severe stall and low efficiency. Therefore, the authors proposed two unique turbines for bi-directional flow: Wells turbine with booster and counter-rotating impulse turbine. Extensive numerical works were conducted to perform a comparative study between the conventional and proposed turbines.